ACS Publications. Most Trusted. Most Cited. Most Read
Semisynthetic Glycoconjugate Vaccine Lead against Klebsiella pneumoniae Serotype O2afg Induces Functional Antibodies and Reduces the Burden of Acute Pneumonia
More

OR SEARCH CITATIONS

My Activity
Publications

Figure 1Loading Img
Download Hi-Res ImageDownload to MS-PowerPointCite This:J. Am. Chem. Soc. 2024, 146, 51, 35356-35366
  • Open Access
Article

Semisynthetic Glycoconjugate Vaccine Lead against Klebsiella pneumoniae Serotype O2afg Induces Functional Antibodies and Reduces the Burden of Acute Pneumonia
Click to copy article linkArticle link copied!

  • Dacheng Shen
    Dacheng Shen
    Department of Bimolecular System, Max Planck Institute of Colloids and Interfaces; 14476 Potsdam, Germany
    Institute of Chemistry and Biochemistry, Freie Universität Berlin, 14195 Berlin, Germany
    More by Dacheng Shen
    Orcidhttps://orcid.org/0000-0002-6633-0219
  • Bruna M. S. Seco
    Bruna M. S. Seco
    Department of Bimolecular System, Max Planck Institute of Colloids and Interfaces; 14476 Potsdam, Germany
    Institute of Chemistry and Biochemistry, Freie Universität Berlin, 14195 Berlin, Germany
    More by Bruna M. S. Seco
  • Luiz Gustavo Teixeira Alves
    Luiz Gustavo Teixeira Alves
    Department of Infectious Diseases, Respiratory Medicine and Critical Care, Charite-Universitätsmedizin Berlin; 10117 Berlin, Germany
    More by Luiz Gustavo Teixeira Alves
    Orcidhttps://orcid.org/0000-0002-5822-4168
  • Ling Yao
    Ling Yao
    Department of Bimolecular System, Max Planck Institute of Colloids and Interfaces; 14476 Potsdam, Germany
    Institute of Chemistry and Biochemistry, Freie Universität Berlin, 14195 Berlin, Germany
    More by Ling Yao
  • Maria Bräutigam
    Maria Bräutigam
    Department of Bimolecular System, Max Planck Institute of Colloids and Interfaces; 14476 Potsdam, Germany
    Institute of Chemistry and Biochemistry, Freie Universität Berlin, 14195 Berlin, Germany
    More by Maria Bräutigam
  • Bastian Opitz
    Bastian Opitz
    Department of Infectious Diseases, Respiratory Medicine and Critical Care, Charite-Universitätsmedizin Berlin; 10117 Berlin, Germany
    German Center for Lung Research (DZL), 12203 Berlin, Germany
    More by Bastian Opitz
    Orcidhttps://orcid.org/0000-0003-1276-836X
  • Martin Witzenrath
    Martin Witzenrath
    Department of Infectious Diseases, Respiratory Medicine and Critical Care, Charite-Universitätsmedizin Berlin; 10117 Berlin, Germany
    German Center for Lung Research (DZL), 12203 Berlin, Germany
    More by Martin Witzenrath
  • Bettina C. Fries
    Bettina C. Fries
    Department of Medicine, Infectious Disease Division, Stony Brook University; Stony Brook, New York 11794, United States
    Veteran’s Administration Medical Center, Northport, New York 11768, United States
    More by Bettina C. Fries
  • Peter H. Seeberger*
    Peter H. Seeberger
    Department of Bimolecular System, Max Planck Institute of Colloids and Interfaces; 14476 Potsdam, Germany
    Institute of Chemistry and Biochemistry, Freie Universität Berlin, 14195 Berlin, Germany
    *Email: [email protected]
    More by Peter H. Seeberger
    Orcidhttps://orcid.org/0000-0003-3394-8466
Open PDFSupporting Information (2)

Journal of the American Chemical Society

Cite this: J. Am. Chem. Soc. 2024, 146, 51, 35356–35366
Click to copy citationCitation copied!
https://doi.org/10.1021/jacs.4c13972
Published December 12, 2024

Copyright © 2024 The Authors. Published by American Chemical Society. This publication is licensed under

CC-BY 4.0 .

Abstract

Click to copy section linkSection link copied!
High Resolution Image
Download MS PowerPoint Slide

Carbapenem-resistant Klebsiella pneumoniae (CR-Kp) bacteria are a serious global health concern due to their drug-resistance to nearly all available antibiotics, fast spread, and high mortality rate. O2afg is a major CR-Kp serotype in the sequence type 258 group (KPST258) that is weakly immunogenic in humans. Here, we describe the creation and evaluation of semisynthetic O2afg glycoconjugate vaccine leads containing one and two repeating units of the polysaccharide epitope that covers the surface of the bacteria conjugated to the carrier protein CRM197. The semisynthetic glycoconjugate containing two repeating units induced functional IgG antibodies in rabbits with opsonophagocytic killing activity and enhanced complement activation and complement-mediated killing of CR-Kp. Passive immunization reduced the burden of acute pneumonia in mice and may represent an alternative to antimicrobial therapy. The semisynthetic glycoconjugate vaccine lead against CR-Kp expressing O2afg antigen is awaiting preclinical development.

This publication is licensed under

CC-BY 4.0 .
  • cc licence
  • by licence
Copyright © 2024 The Authors. Published by American Chemical Society

Subjects

what are subjects

Introduction

Click to copy section linkSection link copied!
Klebsiella pneumoniae is a Gram-negative bacterium naturally occurring in the gastrointestinal tract of humans. Pathogenic strains, when invading other tissues can cause diseases such as pneumonia, urinary tract infection, sepsis, liver abscesses, and meningitis. (1) Hospital-acquired infections (HAIs) are a critical global health crisis affecting millions annually. (2) Carbapenem-resistant K. pneumoniae (CR-Kp) has emerged as a common cause of these infections, with studies reporting mortality rates as high as 30–60%. (3)
The combination of high mortality rate, global dissemination, and their resistance to nearly all currently used antibiotics, resulted in CR-Kp to be classified as an urgent public health threat. (4) A specific CR-Kp lineage belonging to the sequencing type 258 (ST258) is the major cause of infections in the USA and Europe, (5−8) a group that includes the serotype O2afg. (9) The O2afg serotype is found in over 80% of the CR-Kp isolates globally. (10) The O- and K- carbohydrate antigens are well-described virulence factors that contribute to K. pneumoniae survival by avoiding complement-mediated killing. (11,12) Both antigens have been explored as targets for glycoconjugate vaccine development due to their prevalent exposure on the bacterial surface. (13) In contrast to more than 79 K-serotypes, (14) just 12 O-serotypes compose the relevant CR-Kp clinical strains and among those, four serotypes (O1, O2, O3, and O5) are responsible for more than 90% of all K. pneumoniae infections worldwide. (15) Serotypes O1 and O2 are particularly important as they are associated with high antimicrobial resistance and high prevalence. (16−18) Although K. pneumoniae O2afg strains are markedly more serum sensitive than the O1 strains, humans produce very low numbers of specific B cells against the O2afg antigens. The poor immunogenicity of O2afg antigens may explain the high frequency of CR-Kp global propagation of this serotype. (18)
Licensed glycoconjugate vaccines against Haemophilus influenzae type B, meningococcus, Streptococcus pneumoniae, and Salmonella typhi (19,20) are very effectively used to protect humans. K. pneumoniae vaccines based on whole cell preparations or subunits (21) have been studied extensively. A multivalent O-antigen glycoconjugate vaccine lead containing O1, O2, O3, and O5 serotypes conjugated to Pseudomonas aeruginosa flagellin A or B proteins resulted in high IgG-titers in rabbits against all antigens including the carrier proteins and protected mice against K. pneumoniae infection. The vaccine candidate did not enter clinical trials, likely due to the adverse effects caused by the endotoxin lipid A from bacterial cultures. (22) The Phase I/II study of a tetravalent bioconjugate vaccine candidate (kleb4 V) targeting four O-serotypes was completed, but results remain unpublished. (23)
Here, we report the chemical synthesis of two defined O-antigen oligosaccharides containing one or two repeating units resembling the O2afg serotype and the immune response of CRM197 glycan conjugates in rabbits. Passive immunization with antibodies that target the O2afg serotype glycans was also evaluated in a murine model of acute pneumonia.

Results

Click to copy section linkSection link copied!

Synthetic Strategy to Obtain Epitopes Mimicking Natural Occurring O2afg Antigen

K. pneumoniae O2afg serotype bacteria are covered by polysaccharides composed of d-galactan-III (Gal-III) (→3)-β-d-Galf-(1 → 3)-[α-d-Galp-(1 → 4)]-α-d-Galp-(1→) repeating units (RUs) (16) (Figure 1A). We synthesized two oligosaccharide antigens mimicking the natural occurring trisaccharide containing one RU (1) and an hexasaccharide containing two RUs (Figure 1B). A fluorinated C3 aminoalkyl linker (24) at the reducing end of both antigens allowed for efficient conjugation to the carrier protein and immobilization on microarrays.

Figure 1

Figure 1. Glycoconjugate vaccine design and retro-synthetic analysis to obtain the epitopes. (A) Trisaccharide repeating unit of Gal-III from KPST258. (B) Synthetic trisaccharide repeating unit 1 and hexasaccharide 2 containing two repeating units, each connected to an amine linker. (C) Retrosynthetic analysis of trisaccharide 1 and hexasaccharide 2.

High Resolution Image
Download MS PowerPoint Slide
The dense antigen structure with branching at the C3 and C4 positions of the central Galps to the bridging Galf residue, and the presence of fragile Galf glycosidic bonds renders the synthesis challenging. No syntheses of the K. pneumoniae O2afg antigens have been reported so far.
The core galactopyranose of our target trisaccharide 1 connects to the other two sugar residues via C3 and C4 while its anomeric position is connected to a linker. The key strategic consideration is the design of core Galp building block 4. It needs to be glycosylated with building blocks 5 and 6 and connected to linker 7 on correct positions with proper stereo selectivity. Protected hexasaccharide 8 is assembled by combining two building blocks with trisaccharide-repeating-unit structures together, donor 9 and acceptor 10 (Figure 1C).

Synthesis of Trisaccharide 1 and Hexasaccharide 2

The acetyl esters on C4 and C6 of galactopyranose building block 5 participate to ensure α-glycoside formation, (25) galactofuranose 6, and 2,2-difluoro-5-aminopropanol linker 7 favoring α-glycosylation (26) were prepared in anticipation of the assembly of target trisaccharide 1. Core building block 4 was synthesized from commercially available β-d-galactose pentaacetate (see the Supporting Information for details.).
With all of the building blocks in hand, thioglycoside 4 was reacted with linker 7. Following glycosylation with building block 5 and Fmoc cleavage yielded disaccharide acceptor 11. The H–C coupling constants (∼170 Hz) of both glycosidic linkages confirmed the formation of two α-glycosidic bonds. The β-isomer was not observed by NMR but was detectable by HPLC (α/β = 34:1). The excellent stereoselectivity resulted from the fluorines on the linker and the 4,6-acetyl groups on donor 5, as well as a relatively high reaction temperature. Glycosylation of disaccharide 11 with Galf donor 6 gave the protected trisaccharide 3 (Scheme 1A).

Scheme 1

Scheme 1. Synthesis of Trisaccharide 1 and Hexasaccharide 2: (A) Assembly of Protected Trisaccharide 3: (B) Global Deprotection of 3a
High Resolution Image
Download MS PowerPoint Slide

aGalactofuranose partially cleaved during Pd catalyzed hydrogenation. With one-pot Birch reduction, trisaccharide 1 was obtained without cleavage of the Galf residue. (C) Synthesis of the modified galactofuranose building block 17. (D) Assembly of trisaccharide fragments 9 and 10 for the assembly of hexasaccharide target 2.

Global deprotection of trisaccharide 3 via sodium methoxide-driven ester hydrolysis followed by hydrogenation catalyzed by palladium on carbon resulted in partial decomposition of the product through galactofuranose cleavage. In order to avoid the unwanted side reaction, Birch reduction of 3 yielded target trisaccharide 1 in one-pot (Scheme 1B). The NMR spectra of the product were in agreement with those obtained with isolated polysaccharides (see the Supporting Information).
The synthesis of hexasaccharide 2 containing two repeating units was based on the assembly of protected trisaccharide 3. For that purpose, the C3 hydroxyl group on Galf building block 6 was masked with a temporary protective group that could later be cleaved to reveal the site for extension. Benzoylation of Galf 14 gave C2 benzoylated 15 ready for subsequent C3 silylation. (27) Due to the vulnerability of the isopropylidene group during acidic glycosylation conditions, it was replaced with benzoyl esters at the C5 and C6 positions to obtain building block 17 (Scheme 1C).
Union of building block 17 and disaccharide 11 yielded trisaccharide 18. Attempts to cleave the TBS ether on the galactofuranose with TBAF resulted in concomitant loss of the acetyl groups. Addition of acetic acid ensured silyl ether cleavage only to furnish trisaccharide acceptor 10 in 98% yield. Trisaccharide donor 9 was synthesized from monosaccharide 4. Without a linker present at the reducing end, the anomeric thiol leaving group must be retained through subsequent glycosylations. Therefore, thioglycosides 5 and 6 were converted into the corresponding glycosyl trifluoroacetimidates 19 and 22. (28) Activation of donors 19 and 22 was achieved with TMSOTf as a promotor instead of TfOH/NIS in order to keep the thiol unaffected (Scheme 1D).
Coupling of trisaccharide donor 9 and acceptor 10 was unsuccessful, yielding acceptor 10 that unreacted and hydrolyzed trisaccharide 23. Replacing the anomeric thiol by an acetimidate solved a similar problem during the synthesis of a N. meningitidis LPS oligosaccharide previously. (29) Hydrolyzed trisaccharide 23 was recovered and converted into trifluoroacetimidate 24 that was utilized to glycosylate 10 successfully and to obtain protected hexasaccharide 8 in 63% yield. Birch reduction of 8, desalting and HPLC purification provided hexasaccharide 2, ready for further conjugation on microarrays or carrier proteins.

Antibodies from CR-Kp Infected Patients Recognize Synthetic O2afg-Antigens

Determining the epitope specificity of antibodies is crucial for glycoconjugate vaccine design since the target antigen should generate specific antibodies after immunization. (30) Humans infected with CR-Kp produce antiglycan antibodies that reflect the interaction between the host immune system and the bacterial antigens. (31) In search of a minimal oligosaccharide epitope, sera of CR-Kp infected patients were analyzed using synthetic antigens immobilized on microarrays. Human IgGs produced after infection bound to synthetic trisaccharide 1 and hexasaccharide 2. Hexasaccharide epitope 2 was significantly better recognized by human antibodies than trisaccharide 1, when compared to the negative sera control (Figure 2). Thus, hexasaccharide epitope 2 was selected for subsequent vaccination studies.

Figure 2

Figure 2. Determination of human antibody binding to synthetic O-antigens derived from O2afg serotype. (A) Synthetic glycans 1 and 2 were immobilized on a glass slide and sera from CRK-Kp infected patients, and healthy human were incubated with the antigens. Antibody binding was determined by using a glycan microarray assay, and the fluorescence intensity indicates the number of bound IgG antibodies. (B) Graphs showed the titer of bound human IgG antibodies to either O2afg trisaccharide 1 (on the left) or the hexasaccharide 2 (on the right). Both antigens showed positive antibody binders, but only the hexasaccharide showed a significant increase in fluorescence intensity, when compared to the negative control group. A trisaccharide containing the 6-deoxy hexose l-rhamnose (Rha) was used as human antibody positive control. The analysis was performed using the unpaired t-test of individual serum mean values from triplicate printed glycan spots. CRKP─carbapenem-resistant K. pneumoniae, MFI─mean fluorescence intensity in human sera evaluated by glycan array (left panel), and the mean fluorescence intensity of bound antibodies to O2afg synthetic hexasaccharide from different groups was compared (graph on the right). The sera at time point 0 h was collected as control of preinfection. Two-way ANOVA was used in the analysis. The data represent the mean of MFI values from triplicated printed spots of three individuals per group ±95% CI. **p < 0.01.

High Resolution Image
Download MS PowerPoint Slide

Glycoconjugate Vaccine Candidate Preparation and Characterization

Even though humans generate antibodies against the O2afg epitope, the immune response is weak and not long-lasting. (18,32) The conjugation of poorly immunogenic oligosaccharides to carrier proteins boosts a T-cell-dependent, glycan-specific, and long-lasting immune response. (33,34) CMR197, a nontoxic mutant of diphtheria toxin that has already been used in marketed glycoconjugate vaccines, was selected as carrier protein. (35) Synthetic O2afg hexasaccharide 2 was conjugated to CRM197 by coupling the oligosaccharide to the primary amine side chains of lysine residues and the N-terminus of the protein using a p-nitrophenyl adipate ester (PNP) as a linker (Figure S1). Conjugation success was confirmed by SDS-PAGE, comparing the shifts of conjugate mass to unconjugated carrier protein, and the estimation of antigen loading (protein/glycan molar ratio) was based on differences of masses between CRM197 and CRM197-glycan conjugate determined by MALDI-TOF MS. The average antigen loading for CRM197-2 was 5.2 and was used to calculate the glycan dose for the vaccine (Figure S2).

Formulated Glycoconjugate Vaccine Evokes the Production of Anti-O2afg Specific Antibodies in Vivo

After CRM197-2 was formulated with aluminum hydroxide (alum) that is approved for use in humans, the vaccine candidate was used in an immunization study to establish the antibody response in vivo. A very important factor in vaccine development is the choice of animal models. Mice are the most commonly used animal model due to their low cost and straightforward management. Contrary, rabbits are more expensive and demand larger facilities. However, their immune system is evolutionarily closer to the human counterpart. Knowing that the rabbit immune system allows for somatic maturation that is recognized to be an important factor for the successful generation of antiglycan antibodies, (36) we selected rabbits as our model system for this study.
The immunogenicity of CRM197-2 formulated with alum was tested on rabbits. Eight rabbits were divided into two groups. The first group contained five individuals that were immunized intramuscularly (i.m.) with 1 μg of CRM197-2 vaccine per dose. The second group consisted of three animals that received the same vaccine formulation with PBS instead of the glycoconjugate. The control group contained fewer animals to reduce the use of animals in the experiments since PBS with alum formulations are known to induce no immune response with specific antibodies. The vaccination scheme was based on a well-established three-dose schedule, (37,38) with a first vaccine dose followed by two boosts with a 14 day interval between each injection. The long-term immune response was measured after a boost injection three and a half months after the last immunization, and the analysis of the antibody response was measured 11 days postimmunization. The antibody titer against the synthetic antigen was measured by ELISA (Figure 3A).

Figure 3

Figure 3. Rabbits immunized with CRM197-2 produce antibodies that recognize both LPS epitopes 1 and 2. (A) Schematic schedule for rabbit immunization. Five individuals were immunized on day 0 with CRM197-2 (1 μg antigen per dose) formulated in alum and boosted on days 14 and 28 with the same formulation. The long-term immune response was measured 11 days after a boost injection on day 133. Negative control group containing three individuals received PBS with alum. (B) Levels of IgG specific to the hexasaccharide 2. (C) Levels of IgG specific against the trisaccharide 1. (D) Levels of IgA specific to the hexasaccharide 2. (E) Levels of IgA specific antibody against the trisaccharide 1. The data represent the 95% CI distribution of five animals in the CRM197-2 group and three animals in the PBS group. Two-way ANOVA was used for statistical analysis. MFI─mean fluorescence intensity measured by ELISA. *p < 0.05 and **p < 0.01.

High Resolution Image
Download MS PowerPoint Slide
The results showed that the glycoconjugate formulation with CRM197-2 induced a robust immune response in rabbits with increased IgG titer after the first boost (day 21). A significantly higher antibody titer was achieved after the second boost (day 35). After a resting period, the animals were immunized on day 133 again with the same vaccine formulation. The concentration of antigen-specific IgGs in the serum was rapidly restored, reaching the same level, observed after the second boost (day 35), within 11 days postimmunization (day 144) (Figure 3B). This rapid increase in the antibody level indicated the pre-existence of memory B cells, which were restimulated with the antigen, promptly differentiated into plasma cells and secreted large quantities of antibodies. (39) The anti-O2afg antibodies bound to both synthetic antigens, confirming that the O2afg trisaccharide 1 is the minimal repeating unit recognized by the immune system (40) (Figure 3C). Interestingly, the glycoconjugate vaccination also induced the production of specific IgA that recognized both hexasaccharide 2 and trisaccharide 1, although the levels of generated IgAs were much lower than those of IgGs (Figure 3D,E). The IgA antibody class is important to combat pathogens causing respiratory infection and the residents of human microbiota, as is the case for K. pneumoniae.
Native O2afg antigen induces a poor inflammatory immune response, impairing the generation of long-lasting immunity and a robust antibody response. (41) With the conjugation of the synthetic antigen to a carrier protein, we successfully induced an immune response with high antibody titers, overcoming the lower immunogenicity of the glycan antigen. In summary, 1 μg of conjugated glycan induced a robust immune response in rabbits with the production of specific IgGs and IgAs against the synthetic antigen. Since rabbits have proven to be a better animal model than mice, when translating vaccine response to humans, (36) our vaccine lead is likely to evoke a strong immune response in humans with the advantage of using a lower dose than marketed vaccines.
Rabbit anti-O2afg IgG antibodies, generated after glycoconjugate vaccination, recognize exclusively the native O2afg antigen and have opsonophagocytic killing activity
The key to immunization with semisynthetic glycoconjugates is to trigger the production of antibodies against specific epitopes. More importantly, these antibodies have to be able to recognize native antigens on the bacterial surface in order to protect the host against an infection caused by the pathogen. To determine whether the rabbit anti-O2afg IgG antibody generated recognize the native O2afg antigen on K. pneumoniae, pooled polyclonal sera of rabbits, immunized with CRM197-2 vaccine from the time point day 35, were incubated with K. pneumoniae expressing O2afg antigens. Bacteria cells bound by the rabbit antibody were quantified with a flow cytometer using a fluorescent-labeled antirabbit-IgG secondary antibody. A strain expressing the O1 antigen was used as a negative control.
The results showed that rabbit anti-O2afg IgG antibodies recognized native antigens on the surface of the bacteria, while PBS control group IgGs showed no binding. None of the sera had antibodies bound to unrelated O1 antigen. Importantly, anti-O2afg IgGs from rabbits that received the glycoconjugate vaccine lead did not cross-react with O1 K. pneumoniae serotype, indicating that the vaccine induced exclusively IgG antibodies against the O2afg antigen (Figure 4A,B). The RUs of both bacterial serotypes used in the assay share a (→3)-β-d-Galf-(1 → 3)-α-d-Galp-(1→) disaccharide. However, no cross-reactivity was observed with the K. pneumoniae O1 serotype, underscoring the significance of the branching structure in conferring specificity.

Figure 4

Figure 4. Rabbit anti-O2afg IgG binding assay measured by flow cytometry and opsonophagocytic killing activity. (A,B) K. pneumoniae O2afg or O1 were incubated with sera from day 35 (diluted 1:100) from rabbits immunized with either glycoconjugate (CRM197-2 group, red) or PBS (PBS group, blue). A negative control containing bacteria with fluorescent secondary antibody was used as reference to establish the threshold for positive binding (Figure S4). The positive bind quantification shown in the right panel (MFI) was based on the product of the percent of gated events that passed the fluorescence threshold and the median fluorescence of those events that passed the threshold. MFI─mean fluorescence intensity, K. pn─K. pneumoniae. The error bars represent the SD of three independent experiments. One-way ANOVA was used for statistical analysis. **p < 0.01. (C–H) Killing activity of antibodies present in the sera of rabbits was evaluated with K. pneumoniae expressing a capsule (C,D) and a mutant strain without capsule (F,G). The opsonic index represents the sera dilution for 50% of bacteria killing (E,H) and was based on a four-parameter linear regression of sera dilution curves from two independent assays performed in duplicate. The percentage bacterial killing data (D,G) were mean ± SD of colony-forming units (CFUs) reduction relative to negative control (sample lacking sera with complement and effector cells) of two independent assays performed in duplicate. Unpaired t-test was used in the analysis. *p < 0.05, **p < 0.01.

High Resolution Image
Download MS PowerPoint Slide
Antibodies that recognize the O2afg antigen are very rare in patients infected with CR-Kp, even though the incidence of the O2afg serotype in the CR-Kp group is over 80%. This effect results from the weak activation of the immune system by a lower molecular weight of O2afg antigen, when compared to other serotypes. Consequently, very few specific B cells against this antigen are produced. (18) To date, there has been no report of antibodies specifically targeting Gal-III (O2afg). However, some studies have successfully produced anti-O1 and anti-O2 monoclonal antibodies (mAb) and polyclonal sera using animal models infected with respective K. pneumoniae serotypes. (18,42,43) This is expected as in vitro antibody production relies on isolating specific B cells. The low immunogenicity and frequency of B cells targeting the O2afg antigen significantly hinder antibody generation against this target. Overcoming the inherent low immunogenicity of O2afg, our glycoconjugate elicited antibody production against both the synthetic and native antigen forms. Notably, the low-molecular weight of O2afg likely precluded T-independent B-cell activation during infection. In contrast, our glycoconjugate vaccine lead stimulated T-dependent B-cell activation. (44) Antibodies targeting specifically CR-Kp are crucial as other K. pneumoniae strains are commensal gut microbiota. Thus, the generated antibodies selectively eliminate pathogenic CR-Kp while sparing beneficial gut bacteria.
To verify the functional efficacy of vaccine-induced antibodies in eliminating the target microorganism, an opsonophagocytic killing activity (OPKA) assay (45) was conducted. This method is widely employed to assess the efficacy of vaccine candidates by estimating the antibody-mediated killing potential of sera from vaccinated animals or humans, (46) where serum dilution titers strongly correlate with vaccine potency in inducing protective immunity. (47) The results showed that our synthetic glycoconjugate vaccine lead elicit opsonic antibodies that kill O2afg K. pneumoniae (Figure 4C,D). Antibodies from the group that received the glycoconjugate vaccine lead (CRM197-2) had an opsonic index of 1626.5 while the PBS group had a value of 4.5 (Figure 4E). This represents a 99.6% significant increase in killing activity, confirming that the glycoconjugate induces the production of opsonic antibodies. Since K. pneumoniae are known to express thick capsular polysaccharides that can affect the interaction of antibodies with O-antigens, the effect of the capsule in the antibody binding interaction was evaluated using identical serum and OPKA conditions with a mutant acapsular strain (K. pneumoniae K−). Glycoconjugate-induced antibodies were also able to kill the acapsular strain (Figure 4F,G) with a 21 times higher opsonic index (Figure 4H) when compared with the capsular strain (K. pneumoniae K+) (Figure 4E). Here, we confirmed that our O2afg glycoconjugate vaccine lead induces the production of anti-O2afg antibodies harboring opsonophagocytic killing activity, hence a great potential to fight CR-Kp infections.

Anti-O2afg Antibodies Passively Transferred into Mice Reduce Burden in an Acute Pneumonia Model

To test the protective features of the anti-O2afg antibodies generated by our construct, we administrated antibodies on mice 2 h after infection with CR-Kp, as a strategy for passive immunization, terminating the experiment 48 h post infection (Figure 5A). The administration of rabbit antibodies into noninfected mice did not affect their body temperature, indicating that receiving antibodies from different species did not cause a burden for the animal (Figure S5). This result encourages interspecies passive immunization, with rabbits and horses being potential producers of polyclonal sera against infectious diseases. (48)

Figure 5

Figure 5. Passive immunization in a murine pneumonia model. (A) Mice were intranasally infected with 1 × 108 of O2afg-CR-Kp, and 2 h later passively immunized with polyclonal sera of rabbits vaccinated with either synthetic anti-O2afg vaccine (CRM197-2) or PBS vaccine (PBS). Lung, BALF, and blood were collected 48 h postinfection. Mice infected with PBS (PBSinf) but receiving CRM197-2 polyclonal rabbit sera were used as negative control. (B) Lung (left), BALF (middle), and blood (right) were collected 48 h postinfection and analyzed for bacterial burden by quantifying CFU counting. (C) Myeloperoxidase (MPO) activity and lung permeability were measured in BALF of mice infected with CR-Kp 48 h postinfection. Levels of MPO was measured by its enzymatic activity against TMB substrate. Lung permeability was measured by the amount of total protein present in BALF. The data represent the mean ± SE of 12 mice per group. Mann–Whitney was used for the statistical analysis. **p < 0.01 and ****p < 0.0001. One mouse was excluded from the Kpn-infected PBS group due to death after narcosis, and one mouse outlier was excluded from the CR-Kp-infected CRM197-2 group. (D) Lung sections stained with hematoxylin and eosin (H&E) from mice noninfected (PBSInf), mice infected and treated with polyclonal sera of rabbits immunized with O2afg vaccine (Kpn + CRM197-2), and mice infected and treated with polyclonal of rabbits vaccinated with PBS (Kpn + PBS), 48 h postinfection. (E) Histopathology scores of the lungs of mice. From left to right: total cells in lungs; inflammation score of lungs; alveolar edema of lungs; and perivascular edema of lungs. The data represent the mean ± SE of five mice per group. Kruskal–Wallis was used for the statistical analysis. *p < 0.05 and **p < 0.01.

High Resolution Image
Download MS PowerPoint Slide
Pneumonia and sepsis are the primary causes of mortality in patients infected with CR-Kp, (49) with pneumonia being the most frequent cause of sepsis. Consequently, decreasing the number of bacterial colony-forming units (CFUs) in the lungs is crucial for mitigating inflammation and preventing the progression of pneumonia to sepsis. Here, mice that received anti-O2afg polyclonal sera had a significant reduction of more than one-log in bacteria CFU in the lungs and bronchoalveolar lavage fluid (BALF) when compared to the infected group that received polyclonal sera without anti-O2afg antibodies (Figure 5B left and middle). This suggests that the presence of anti-O2afg antibodies was the cause of the bacterial clearance in the lungs and BALF. Therefore, the observed reduction of CFU in BALF was a very important factor to limit the spread of CR-Kp in the body. The presence of bacteria in the alveolar space (measured in BALF) may lead to an exacerbated inflammation of the lung tissue, followed by epithelial cell damage and a breach of the alveolar epithelial barrier, possibly facilitating bacterial entry into the bloodstream. However, blood analysis of infected mice revealed no bacteria in the bloodstream across all groups (Figure 5B right), suggesting that the clinical CR-Kp isolate used in this study is of limited invasiveness in mice and therefore insufficient to induce bacteremia.
Myeloperoxidase (MPO) is a cytotoxic enzyme with antimicrobial activity, mainly produced in neutrophil granulocytes. It can also be associated with increased lung permeability due to its cytotoxic nature, contributing to acute pulmonary inflammation and epithelial lung tissue injury. (50) In order to estimate the protective effect of anti-O2afg antibodies in infected lungs, MPO levels and lung permeability were measured in BALF samples from infected animals after administration of the passive immunization with rabbit antibodies vaccinated with either CRM197-2 or PBS alum. Anti-O2afg antibodies significantly reduced the levels of MPO present in the lungs of infected mice as well as lung permeability, compared to the group that received PBS polyclonal sera (Figure 5C). Immune cell counts and cytokine production were also assessed in blood and BALF samples. The passive immunization with anti-O2afg antibodies led to an increase in the number of immune cells in blood, including neutrophils, monocytes, and eosinophils. Contrarily, the number of neutrophils and inflammatory monocytes, directly related to the increase in lung tissue damage, were significantly lower than that in the control infected group. The number of alveolar macrophages was similar among these two groups (Figure S6). It was reasonable to think that a reduced MPO expression might be correlated with the reduced number of neutrophils infiltrating the lung space, as seen by flow cytometry, as they are the main cell type responsible for MPO production. The production of inflammatory cytokines was also affected by the passive immunization with anti-O2afg antibodies, with a significant increase in the level of IL-12_p70, IL-6, CXCL1, and IFN-γ in blood, when compared to the other infected group. In BALF, a significant increase was only seen for IL-12_p70 and IL-6, while levels of IL-17α were reduced after treatment with anti-O2afg antibodies, comparing to the other infected group (Figure S7).
Histopathology has been a cornerstone method for assessing morphological changes in lung infection models for decades. Relying on qualitative diagnoses of microscopic tissue alterations, it involves certified pathologists applying a semiquantitative scoring system to compare lesion severity between treatment and control groups. (51,52) Compared with uninfected controls, the lungs of infected mice exhibited increased inflammation and edema, confirming the development of acute lung injury (ALI) (Figure 5D). However, no significant difference in total cell count was observed between groups. While anti-O2afg polyclonal sera did not reduce inflammation scores or alveolar edema compared with PBS controls, it did significantly ameliorate perivascular edema in infected mice, reaching levels comparable to uninfected animals (Figure 5E).
Edema is a hallmark of ALI, resulting from increased capillary permeability caused by endothelial barrier damage, which allows fluid to accumulate in perivascular spaces. (53,54) In K. pneumoniae-induced ALI, lung injury is correlated with elevated neutrophil counts and myeloperoxidase activity. (55) The reduced neutrophil and MPO levels observed in the BALF of mice treated with anti-O2afg antibodies together with a reduction in the cell counts of inflammatory monocytes may therefore explain the attenuation in tissue damage, as seen by reduced perivascular edema formation and the protein infiltration in the alveolar space of infected mice. Previous studies have demonstrated that decreased neutrophil and MPO levels in the BALF are associated with improved outcomes in influenza-induced acute respiratory distress syndrome and cystic fibrosis. (56,57) Consequently, the beneficial effects of anti-O2afg antibodies on lung and BALF parameters suggest their potential to enhance the survival rates in CR-Kp-infected mice. (58−63)

Discussion

Click to copy section linkSection link copied!
Bacterial infections remain a leading cause of mortality worldwide, disproportionately affecting immuno-compromised and hospitalized individuals as well as the elderly. The emergence of antimicrobial-resistant strains, such as carbapenem-resistant K. pneumoniae (CR-Kp), exacerbates this crisis. While antibody-based therapies and vaccine development have been more deeply explored, targeting the highly variable capsular polysaccharide structure has proven challenging due to its limited epidemiological correlations. In contrast, the O-antigen, with fewer serotypes and broader coverage, represents a more promising target.
Despite the potential of O-antigen-based vaccines, existing approaches using inactivated bacteria or isolated O-antigens are hindered by the presence of toxic endotoxins. To address this, we developed a synthetic hexasaccharide mimicking the O2afg serotype, which is a predominant CR-Kp strain. Conjugation to the carrier protein CRM197 and adsorption to alum created a safe and immunogenic semisynthetic glycoconjugate vaccine lead.
Unlike other O-antigens, O2afg exhibits poor immunogenicity, limiting antibody production. However, our vaccine lead successfully elicited a robust immune response in rabbits, generating IgG and IgA antibodies that recognized both the synthetic and native O2afg antigens. These antibodies promoted bacterial clearance through opsonization and complement activation, demonstrating the vaccine’s efficacy. Notably, the low vaccine dose required underscores its potential cost-effectiveness and translational potential.
K. pneumoniae is a primary cause of hospital-acquired pneumonia. Critically ill patients, in particular, are particularly susceptible to infections caused by this bacterium. Our study demonstrated the therapeutic effects of anti-O2afg antibodies in murine pneumonia, reducing bacterial burden, inflammation, and lung injury.

Conclusions

Click to copy section linkSection link copied!
In summary, we have developed a novel, semisynthetic glycoconjugate vaccine lead targeting O2afg-CR-Kp, a significant step toward addressing the urgent threat of antimicrobial resistance. The vaccine’s ability to induce a protective immune response and overcome the challenges associated with traditional vaccine approaches holds promise for future clinical development and broader application against resistant pathogens.

Supporting Information

Click to copy section linkSection link copied!

The Supporting Information is available free of charge at https://pubs.acs.org/doi/10.1021/jacs.4c13972.

  • Experimental methods and characterization, including synthesis of the compounds, glycan microarray studies, conjugation, with in vitro and in vivo assays to evaluate the vaccine lead (PDF)

  • 1H-, 13C-, and HSQC-NMR spectra for new compounds (PDF)

Terms & Conditions

Most electronic Supporting Information files are available without a subscription to ACS Web Editions. Such files may be downloaded by article for research use (if there is a public use license linked to the relevant article, that license may permit other uses). Permission may be obtained from ACS for other uses through requests via the RightsLink permission system: http://pubs.acs.org/page/copyright/permissions.html.

Author Information

Click to copy section linkSection link copied!
  • Corresponding Author
    • Peter H. Seeberger - Department of Bimolecular System, Max Planck Institute of Colloids and Interfaces; 14476 Potsdam, Germany;  Institute of Chemistry and Biochemistry, Freie Universität Berlin, 14195 Berlin, Germany;  Orcidhttps://orcid.org/0000-0003-3394-8466;  Email: [email protected]
  • Authors
    • Dacheng Shen - Department of Bimolecular System, Max Planck Institute of Colloids and Interfaces; 14476 Potsdam, Germany;  Institute of Chemistry and Biochemistry, Freie Universität Berlin, 14195 Berlin, Germany;  Present Address: School of Chemistry and Chemical Engineering, Zhejiang Sci-Tech University, Hangzhou, China;  Orcidhttps://orcid.org/0000-0002-6633-0219
    • Bruna M. S. Seco - Department of Bimolecular System, Max Planck Institute of Colloids and Interfaces; 14476 Potsdam, Germany;  Institute of Chemistry and Biochemistry, Freie Universität Berlin, 14195 Berlin, Germany;  Present Address: BioNTech SE; Mainz, Germany
    • Luiz Gustavo Teixeira Alves - Department of Infectious Diseases, Respiratory Medicine and Critical Care, Charite-Universitätsmedizin Berlin; 10117 Berlin, Germany;  Present Address: Berlin Institute for Medical Systems Biology of the Max Delbrück Center; Berlin, Germany;  Orcidhttps://orcid.org/0000-0002-5822-4168
    • Ling Yao - Department of Bimolecular System, Max Planck Institute of Colloids and Interfaces; 14476 Potsdam, Germany;  Institute of Chemistry and Biochemistry, Freie Universität Berlin, 14195 Berlin, Germany
    • Maria Bräutigam - Department of Bimolecular System, Max Planck Institute of Colloids and Interfaces; 14476 Potsdam, Germany;  Institute of Chemistry and Biochemistry, Freie Universität Berlin, 14195 Berlin, Germany
    • Bastian Opitz - Department of Infectious Diseases, Respiratory Medicine and Critical Care, Charite-Universitätsmedizin Berlin; 10117 Berlin, Germany;  German Center for Lung Research (DZL), 12203 Berlin, Germany;  Orcidhttps://orcid.org/0000-0003-1276-836X
    • Martin Witzenrath - Department of Infectious Diseases, Respiratory Medicine and Critical Care, Charite-Universitätsmedizin Berlin; 10117 Berlin, Germany;  German Center for Lung Research (DZL), 12203 Berlin, Germany
    • Bettina C. Fries - Department of Medicine, Infectious Disease Division, Stony Brook University; Stony Brook, New York 11794, United States;  Veteran’s Administration Medical Center, Northport, New York 11768, United States
  • Author Contributions

    The manuscript was written through contributions of all authors. All authors have given approval to the final version of the manuscript.

  • Funding

    Open access funded by Max Planck Society. Veterans Administration (VA) Merit I01BX003741–01A2 (BCF). The content is solely the responsibility of the authors and does not necessarily represent the official views of the NIH, VA, or the United States government.

  • Notes
    The authors declare no competing financial interest.

Acknowledgments

Click to copy section linkSection link copied!

We thank the Max-Planck Society for generous financial support. We thank B.C.F. (Stony Brook University NY, USA) for kindly providing us serum samples. We are grateful to Prof. M.W. and Prof. B.O. (Charite-Universitätsmedizin Berlin, Germany) for the help with animal experiments. We thank Prof. Dr. Chris Whitfield (University of Guelph, Canada) for kindly donating well-characterized bacterial samples. We also thank Dr. Katrin Reppe (Max Planck Institute of Molecular Cell Biology and Genetics, Germany) and Dr. Birgitt Gutbier (Charité-Universitätsmedizin Berlin, Germany) for the guidance and assistance during passive immunization.

References

Click to copy section linkSection link copied!

This article references 63 other publications.

  1. 1
    Li, B.; Zhao, Y.; Liu, C.; Chen, Z.; Zhou, D. Molecular pathogenesis of Klebsiella pneumoniae. Future Microbiol. 2014, 9 (9), 1071– 1081,  DOI: 10.2217/fmb.14.48
    Google Scholar
    There is no corresponding record for this reference.
  2. 2
    Global Report on Infection Prevention and Control; World Health Organization, 2022.
    Google Scholar
    There is no corresponding record for this reference.
  3. 3
    Lou, T.; Du, X.; Zhang, P.; Shi, Q.; Han, X.; Lan, P.; Yan, R.; Hu, H.; Wang, Y.; Wu, X. Risk factors for infection and mortality caused by carbapenem-resistant Klebsiella pneumoniae: A large multicentre case-control and cohort study. J. Infect. 2022, 84 (5), 637– 647,  DOI: 10.1016/j.jinf.2022.03.010
    Google Scholar
    There is no corresponding record for this reference.
  4. 4
    Antibiotic resistance threats in the United States, 2019; Centers for Disease Control and Prevention (U.S.); National Center for Emerging Zoonotic and Infectious Diseases (U.S.). Division of Healthcare Quality Promotion. Antibiotic Resistance Coordination and Strategy Unit., 2019.
    Google Scholar
    There is no corresponding record for this reference.
  5. 5
    Marsh, J. W.; Mustapha, M. M.; Griffith, M. P.; Evans, D. R.; Ezeonwuka, C.; Pasculle, A. W.; Shutt, K. A.; Sundermann, A.; Ayres, A. M.; Shields, R. K. Evolution of Outbreak-Causing Carbapenem-Resistant Klebsiella pneumoniae ST258 at a Tertiary Care Hospital over 8 Years. mBio 2019, 10 (5), e01945  DOI: 10.1128/mbio.01945-19
    Google Scholar
    There is no corresponding record for this reference.
  6. 6
    Munoz-Price, L. S.; Poirel, L.; Bonomo, R. A.; Schwaber, M. J.; Daikos, G. L.; Cormican, M.; Cornaglia, G.; Garau, J.; Gniadkowski, M.; Hayden, M. K. Clinical epidemiology of the global expansion of Klebsiella pneumoniae carbapenemases. Lancet Infect. Dis. 2013, 13 (9), 785– 796,  DOI: 10.1016/S1473-3099(13)70190-7
    Google Scholar
    6
    Clinical epidemiology of the global expansion of Klebsiella pneumoniae carbapenemases
    Munoz-Price L Silvia; Poirel Laurent; Bonomo Robert A; Schwaber Mitchell J; Daikos George L; Cormican Martin; Cornaglia Giuseppe; Garau Javier; Gniadkowski Marek; Hayden Mary K; Kumarasamy Karthikeyan; Livermore David M; Maya Juan J; Nordmann Patrice; Patel Jean B; Paterson David L; Pitout Johann; Villegas Maria Virginia; Wang Hui; Woodford Neil; Quinn John P
    The Lancet. Infectious diseases (2013), 13 (9), 785-96 ISSN:.
    Klebsiella pneumoniae carbapenemases (KPCs) were originally identified in the USA in 1996. Since then, these versatile β-lactamases have spread internationally among Gram-negative bacteria, especially K pneumoniae, although their precise epidemiology is diverse across countries and regions. The mortality described among patients infected with organisms positive for KPC is high, perhaps as a result of the limited antibiotic options remaining (often colistin, tigecycline, or aminoglycosides). Triple drug combinations using colistin, tigecycline, and imipenem have recently been associated with improved survival among patients with bacteraemia. In this Review, we summarise the epidemiology of KPCs across continents, and discuss issues around detection, present antibiotic options and those in development, treatment outcome and mortality, and infection control. In view of the limitations of present treatments and the paucity of new drugs in the pipeline, infection control must be our primary defence for now.
    >> More from SciFinder ®
    https://chemport.cas.org/services/resolver?origin=ACS&resolution=options&coi=1%3ACAS%3A280%3ADC%252BC3sbitFGktQ%253D%253D&md5=0491bc8ae393c42130affd6ddfdc4063
  7. 7
    Wang, M.; Earley, M.; Chen, L.; Hanson, B. M.; Yu, Y.; Liu, Z.; Salcedo, S.; Cober, E.; Li, L.; Kanj, S. S. Clinical outcomes and bacterial characteristics of carbapenem-resistant Klebsiella pneumoniae complex among patients from different global regions (CRACKLE-2): a prospective, multicentre, cohort study. Lancet Infect. Dis. 2022, 22 (3), 401– 412,  DOI: 10.1016/S1473-3099(21)00399-6
    Google Scholar
    There is no corresponding record for this reference.
  8. 8
    van Duin, D.; Arias, C. A.; Komarow, L.; Chen, L.; Hanson, B. M.; Weston, G.; Cober, E.; Garner, O. B.; Jacob, J. T.; Satlin, M. J. Molecular and clinical epidemiology of carbapenem-resistant Enterobacterales in the USA (CRACKLE-2): a prospective cohort study. Lancet Infect. Dis. 2020, 20 (6), 731– 741,  DOI: 10.1016/S1473-3099(19)30755-8
    Google Scholar
    There is no corresponding record for this reference.
  9. 9
    Choi, M.; Hegerle, N.; Nkeze, J.; Sen, S.; Jamindar, S.; Nasrin, S.; Sen, S.; Permala-Booth, J.; Sinclair, J.; Tapia, M. D. The Diversity of Lipopolysaccharide (O) and Capsular Polysaccharide (K) Antigens of Invasive Klebsiella pneumoniae in a Multi-Country Collection. Front. Microbiol. 2020, 11, 1249,  DOI: 10.3389/fmicb.2020.01249
    Google Scholar
    9
    The Diversity of Lipopolysaccharide (O) and Capsular Polysaccharide (K) Antigens of Invasive Klebsiella pneumoniae in a Multi-Country Collection
    Choi Myeongjin; Hegerle Nicolas; Nkeze Joseph; Sen Shaichi; Jamindar Sanchita; Nasrin Shamima; Sen Sunil; Permala-Booth Jasnehta; Sinclair James; Tapia Milagritos D; Simon Raphael; Cross Alan S; Tennant Sharon M; Choi Myeongjin; Hegerle Nicolas; Nkeze Joseph; Sen Shaichi; Jamindar Sanchita; Nasrin Shamima; Sen Sunil; Permala-Booth Jasnehta; Sinclair James; Simon Raphael; Cross Alan S; Tennant Sharon M; Tapia Milagritos D; Johnson J Kristie; Mamadou Sylla; Thaden Joshua T; Fowler Vance G Jr; Fowler Vance G Jr; Aguilar Ana; Teran Enrique; Decre Dominique; Morel Florence; Krogfelt Karen Angeliki; Brauner Annelie; Protonotariou Efthymia; Christaki Eirini; Christaki Eirini; Shindo Yuichiro; Lin Yi-Tsung; Lin Yi-Tsung; Kwa Andrea L; Kwa Andrea L; Kwa Andrea L; Shakoor Sadia; Singh-Moodley Ashika; Perovic Olga; Jacobs Jan; Jacobs Jan; Lunguya Octavie
    Frontiers in microbiology (2020), 11 (), 1249 ISSN:1664-302X.
    Klebsiella pneumoniae is a common cause of sepsis and is particularly associated with healthcare-associated infections. New strategies are needed to prevent or treat infections due to the emergence of multi-drug resistant K. pneumoniae. The goal of this study was to determine the diversity and distribution of O (lipopolysaccharide) and K (capsular polysaccharide) antigens on a large (>500) global collection of K. pneumoniae strains isolated from blood to inform vaccine development efforts. A total of 645 K. pneumoniae isolates were collected from the blood of patients in 13 countries during 2005-2017. Antibiotic susceptibility was determined using the Kirby-Bauer disk diffusion method. O antigen types including the presence of modified O galactan types were determined by PCR. K types were determined by multiplex PCR and wzi capsular typing. Sequence types of isolates were determined by multilocus sequence typing (MLST) targeting seven housekeeping genes. Among 591 isolates tested for antimicrobial resistance, we observed that 19.3% of isolates were non-susceptible to carbapenems and 62.1% of isolates were multidrug resistant (from as low as 16% in Sweden to 94% in Pakistan). Among 645 isolates, four serotypes, O1, O2, O3, and O5, accounted for 90.1% of K. pneumoniae strains. Serotype O1 was associated with multidrug resistance. Fifty percent of 199 tested O1 and O2 strains were gmlABC-positive, indicating the presence of the modified polysaccharide subunit D-galactan III. The most common K type was K2 by both multiplex PCR and wzi capsular typing. Of 39 strains tested by MLST, 36 strains were assigned to 26 known sequence types of which ST14, ST25, and ST258 were the most common. Given the limited number of O antigen types, diverse K antigen types and the high multidrug resistance, we believe that an O antigen-based vaccine would offer an excellent prophylactic strategy to prevent K. pneumoniae invasive infection.
    >> More from SciFinder ®
    https://chemport.cas.org/services/resolver?origin=ACS&resolution=options&coi=1%3ACAS%3A280%3ADC%252BB38nls1Snug%253D%253D&md5=4d3e3785ff7b236a2d2095d3cf8f1801
  10. 10
    Follador, R.; Heinz, E.; Wyres, K. L.; Ellington, M. J.; Kowarik, M.; Holt, K. E.; Thomson, N. R. The diversity of Klebsiella pneumoniae surface polysaccharides. Microb. Genomes 2016, 2 (8), e000073  DOI: 10.1099/mgen.0.000073
    Google Scholar
    There is no corresponding record for this reference.
  11. 11
    Hsieh, P. F.; Lin, T. L.; Yang, F. L.; Wu, M. C.; Pan, Y. J.; Wu, S. H.; Wang, J. T. Lipopolysaccharide O1 antigen contributes to the virulence in Klebsiella pneumoniae causing pyogenic liver abscess. PLoS One 2012, 7 (3), e33155  DOI: 10.1371/journal.pone.0033155
    Google Scholar
    There is no corresponding record for this reference.
  12. 12
    Opoku-Temeng, C.; Kobayashi, S. D.; DeLeo, F. R. Klebsiella pneumoniae capsule polysaccharide as a target for therapeutics and vaccines. Comput. Struct. Biotechnol. J. 2019, 17, 1360– 1366,  DOI: 10.1016/j.csbj.2019.09.011
    Google Scholar
    12
    Klebsiella pneumoniae capsule polysaccharide as a target for therapeutics and vaccines
    Opoku-Temeng, Clement; Kobayashi, Scott D.; DeLeo, Frank R.
    Computational and Structural Biotechnology Journal (2019), 17 (), 1360-1366CODEN: CSBJAC; ISSN:2001-0370. (Elsevier B.V.)
    A review. Carbapenem-resistant (CR) Klebsiella pneumoniae has emerged as an urgent public health threat in many industrialized countries worldwide, including the United States. Infections caused by CR K. pneumoniae are difficult to treat because these organisms are typically resistant to multiple antibiotics, and the patients have significant comorbidities. Notably, there is high (∼50%) mortality among individuals with bacteremia caused by CR K. pneumoniae. Given the dearth of new antibiotics, and the recent convergence of multidrug resistance and hypervirulence, there is a crit. need for alternative strategies for the treatment of CR K. pneumoniae infections. The capsule polysaccharide (CPS) of K. pneumoniae has long been viewed as an important virulence factor that promotes resistance to phagocytosis and serum bactericidal activity. Thus, the CPS has been targeted previously for the development of therapeutics and vaccines, although there is no licensed CPS-based vaccine or therapy for the treatment of CR K. pneumoniae infections. Here, we discuss immunoprophylactic and immunotherapeutic approaches that have been tested previously for the treatment of Klebsiella infections. We also suggest potential strategies to promote development of CPS-based vaccines and therapies for prevention and treatment of CR K. pneumoniae infections.
    >> More from SciFinder ®
    https://chemport.cas.org/services/resolver?origin=ACS&resolution=options&coi=1%3ACAS%3A528%3ADC%252BC1MXitFOrtbjL&md5=53ffb2dd28430a9cb1bd7a8f966781fd
  13. 13
    Choi, M.; Tennant, S. M.; Simon, R.; Cross, A. S. Progress towards the development of Klebsiella vaccines. Expert Rev. Vaccines 2019, 18 (7), 681– 691,  DOI: 10.1080/14760584.2019.1635460
    Google Scholar
    There is no corresponding record for this reference.
  14. 14
    Wyres, K. L.; Wick, R. R.; Gorrie, C.; Jenney, A.; Follador, R.; Thomson, N. R.; Holt, K. E. Identification of Klebsiella capsule synthesis loci from whole genome data. Microb. Genomes 2016, 2 (12), e000102  DOI: 10.1099/mgen.0.000102
    Google Scholar
    There is no corresponding record for this reference.
  15. 15
    Artyszuk, D.; Jachymek, W.; Izdebski, R.; Gniadkowski, M.; Lukasiewicz, J. The OL101 O antigen locus specifies a novel Klebsiella pneumoniae serotype O13 structure. Carbohydr. Polym. 2024, 326, 121581,  DOI: 10.1016/j.carbpol.2023.121581
    Google Scholar
    There is no corresponding record for this reference.
  16. 16
    Stojkovic, K.; Szijarto, V.; Kaszowska, M.; Niedziela, T.; Hartl, K.; Nagy, G.; Lukasiewicz, J. Identification of d-Galactan-III As Part of the Lipopolysaccharide of Klebsiella pneumoniae Serotype O1. Front. Microbiol. 2017, 8, 684,  DOI: 10.3389/fmicb.2017.00684
    Google Scholar
    There is no corresponding record for this reference.
  17. 17
    Fang, C. T.; Shih, Y. J.; Cheong, C. M.; Yi, W. C. Rapid and Accurate Determination of Lipopolysaccharide O-Antigen Types in Klebsiella pneumoniae with a Novel PCR-Based O-Genotyping Method. J. Clin. Microbiol. 2016, 54 (3), 666– 675,  DOI: 10.1128/JCM.02494-15
    Google Scholar
    There is no corresponding record for this reference.
  18. 18
    Pennini, M. E.; De Marco, A.; Pelletier, M.; Bonnell, J.; Cvitkovic, R.; Beltramello, M.; Cameroni, E.; Bianchi, S.; Zatta, F.; Zhao, W. Immune stealth-driven O2 serotype prevalence and potential for therapeutic antibodies against multidrug resistant Klebsiella pneumoniae. Nat. Commun. 2017, 8 (1), 1991,  DOI: 10.1038/s41467-017-02223-7
    Google Scholar
    There is no corresponding record for this reference.
  19. 19
    Mohan, V. K.; Varanasi, V.; Singh, A.; Pasetti, M. F.; Levine, M. M.; Venkatesan, R.; Ella, K. M. Safety and immunogenicity of a Vi polysaccharide-tetanus toxoid conjugate vaccine (Typbar-TCV) in healthy infants, children, and adults in typhoid endemic areas: a multicenter, 2-cohort, open-label, double-blind, randomized controlled phase 3 study. Clin. Infect. Dis. 2015, 61 (3), 393– 402,  DOI: 10.1093/cid/civ295
    Google Scholar
    19
    Safety and immunogenicity of a Vi polysaccharide-tetanus toxoid conjugate vaccine (Typbar-TCV) in healthy infants, children, and adults in typhoid endemic areas: a multicenter, 2-cohort, open-label, double-blind, randomized controlled phase 3 study
    Mohan, Vadrevu Krishna; Varanasi, Vineeth; Singh, Anit; Pasetti, Marcela F.; Levine, Myron M.; Venkatesan, Ramasamy; Ella, Krishna M.
    Clinical Infectious Diseases (2015), 61 (3), 393-402CODEN: CIDIEL; ISSN:1058-4838. (Oxford University Press)
    Background: Enteric fever caused by Salmonella Typhi remains a major public health problem in developing countries. Typbar-TCV is a single-dose typhoid Vi polysaccharide-tetanus toxoid conjugate vaccine for persons≥6 mo of age. Methods: Six hundred fifty-four healthy subjects aged 2-45 years enrolled in a double-blind, randomized controlled trial (RCT) received a single dose of Typbar-TCV or comparator "Vi polysaccharide" (Typbar), and 327 healthy subjects aged 6-23 mo received a single dose of Typbar-TCV in an open-label trial (OLT); both received single-or multidose presentations from different lots. After 2 years, subsets in each group received a booster dose. The primary objective included anal. of geometric mean titer (GMTs) and 4-fold rise of anti-Vi serum IgG (IgG) ELISA titers over baseline (seroconversion [SCN]) 42 days after immunization. Results: Typbar-TCV recipients in the RCT attained higher anti-Vi IgG GMTs 42 days after immunization (SCN,97%;GMT, 1293 [95% confidence interval {CI}, 1153-1449]) than recipients of Typbar (SCN, 93%; GMT, 411 [95% CI,359-471]) (P <.001). Typbar-TCV was highly immunogenic in the OLT (SCN, 98%; GMT, 1937 [95% CI, 1785-2103]). Two years after vaccination, anti-Vi titers remained higher in Typbar-TCV subjects (GMT, 82 [95% CI, 73-92]); and exhibited higher avidity (geometric mean avidity index [GMAI], 60%) than in Typbar recipients (GMT, 46[95% CI, 40-53];GMAI 46%) in the RCT (P <.001). OLT Typbar-TCV recipients achieved GMT of 48 (95% CI, 42-55)and GMAI of 57%. Typbar-TCV induced multiple IgG subclasses and strong booster responses in all ages. No serious vaccine-attributable adverse events were obsd. Conclusions: Single-dose Typbar-TCV is well tolerated and induces robust and long-lasting serum anti-Vi IgGacross age groups.
    >> More from SciFinder ®
    https://chemport.cas.org/services/resolver?origin=ACS&resolution=options&coi=1%3ACAS%3A528%3ADC%252BC28XhvFakur3J&md5=e6f448c9f352c27c8cd18919d9d24709
  20. 20
    Zhao, J.; Hu, G.; Huang, Y.; Huang, Y. C.; Wei, X.; Shi, J. Y. Polysaccharide conjugate vaccine: A kind of vaccine with great development potential. Chin. Chem. Lett. 2021, 32 (4), 1331– 1340,  DOI: 10.1016/j.cclet.2020.10.013
    Google Scholar
    There is no corresponding record for this reference.
  21. 21
    Ahmad, T. A.; El-Sayed, L. H.; Haroun, M.; Hussein, A. A.; El Ashry, E. S. H. Development of immunization trials against Klebsiella pneumoniae. Vaccine 2012, 30 (14), 2411– 2420,  DOI: 10.1016/j.vaccine.2011.11.027
    Google Scholar
    There is no corresponding record for this reference.
  22. 22
    Hegerle, N.; Choi, M.; Sinclair, J.; Amin, M. N.; Ollivault-Shiflett, M.; Curtis, B.; Laufer, R. S.; Shridhar, S.; Brammer, J.; Toapanta, F. R. Development of a broad spectrum glycoconjugate vaccine to prevent wound and disseminated infections with Klebsiella pneumoniae and Pseudomonas aeruginosa. PLoS One 2018, 13 (9), e0203143  DOI: 10.1371/journal.pone.0203143
    Google Scholar
    There is no corresponding record for this reference.
  23. 23
    Miller, J. C.; Cross, A. S.; Tennant, S. M.; Baliban, S. M. Klebsiella pneumoniae Lipopolysaccharide as a Vaccine Target and the Role of Antibodies in Protection from Disease. Vaccines 2024, 12 (10), 1177,  DOI: 10.3390/vaccines12101177
    Google Scholar
    There is no corresponding record for this reference.
  24. 24
    Schumann, B.; Parameswarappa, S. G.; Lisboa, M. P.; Kottari, N.; Guidetti, F.; Pereira, C. L.; Seeberger, P. H. Nucleophile-Directed Stereocontrol Over Glycosylations Using Geminal-Difluorinated Nucleophiles. Angew. Chem., Int. Ed. 2016, 55 (46), 14431– 14434,  DOI: 10.1002/anie.201606774
    Google Scholar
    There is no corresponding record for this reference.
  25. 25
    Hahm, H. S.; Hurevich, M.; Seeberger, P. H. Automated assembly of oligosaccharides containing multiple cis-glycosidic linkages. Nat. Commun. 2016, 7, 12482,  DOI: 10.1038/ncomms12482
    Google Scholar
    25
    Automated assembly of oligosaccharides containing multiple cis-glycosidic linkages
    Hahm, Heung Sik; Hurevich, Mattan; Seeberger, Peter H.
    Nature Communications (2016), 7 (), 12482CODEN: NCAOBW; ISSN:2041-1723. (Nature Publishing Group)
    Automated glycan assembly (AGA) has advanced from a concept to a com. technol. that rapidly provides access to diverse oligosaccharide chains as long as 30-mers. To date, AGA was mainly employed to incorporate trans-glycosidic linkages, where C2 participating protecting groups ensure stereoselective couplings. Stereocontrol during the installation of cis-glycosidic linkages cannot rely on C2-participation and anomeric mixts. are typically formed. Here, we demonstrate that oligosaccharides contg. multiple cis-glycosidic linkages can be prepd. efficiently by AGA using monosaccharide building blocks equipped with remote participating protecting groups. The concept is illustrated by the automated syntheses of biol. relevant oligosaccharides bearing various cis-galactosidic and cis-glucosidic linkages. This work provides further proof that AGA facilitates the synthesis of complex oligosaccharides with multiple cis-linkages and other biol. important oligosaccharides.
    >> More from SciFinder ®
    https://chemport.cas.org/services/resolver?origin=ACS&resolution=options&coi=1%3ACAS%3A528%3ADC%252BC28XhsVKqs73E&md5=93b9e144bf44840b1ba4927068ed39b0
  26. 26
    Schumann, B.; Parameswarappa, S. G.; Lisboa, M. P.; Kottari, N.; Guidetti, F.; Pereira, C. L.; Seeberger, P. H. Nucleophile-Directed Stereocontrol Over Glycosylations Using Geminal-Difluorinated Nucleophiles. Angew. Chem., Int. Ed. 2016, 55 (46), 14431– 14434,  DOI: 10.1002/anie.201606774
    Google Scholar
    There is no corresponding record for this reference.
  27. 27
    Wang, S.; Meng, X.; Huang, W.; Yang, J.-S. Influence of Silyl Protections on the Anomeric Reactivity of Galactofuranosyl Thioglycosides and Application of the Silylated Thiogalactofuranosides to One-Pot Synthesis of Diverse β-d-Oligogalactofuranosides. J. Org. Chem. 2014, 79 (21), 10203– 10217,  DOI: 10.1021/jo5018684
    Google Scholar
    27
    Influence of Silyl Protections on the Anomeric Reactivity of Galactofuranosyl Thioglycosides and Application of the Silylated Thiogalactofuranosides to One-Pot Synthesis of Diverse β-D-Oligogalactofuranosides
    Wang, Shuai; Meng, Xue; Huang, Wei; Yang, Jin-Song
    Journal of Organic Chemistry (2014), 79 (21), 10203-10217CODEN: JOCEAH; ISSN:0022-3263. (American Chemical Society)
    We describe in this paper the tuning effect of silyl protecting groups on the donor reactivity of galactofuranosyl Ph thioglycosides. Silyl ethers on the galactofuranose ring are found to have an arming effect on the glycosylation reactivity, but the cyclic 3,5-acetal protecting group decreases the reactivity. The reactive Ph 2,6-di-O-Bz-3,5-di-O-TBS-1-thio-β-D-galactofuranoside 3 is proved to be a useful glycosyl building block. By taking advantage of this donor, we achieved the highly efficient one-pot soln.-phase assembly of a panel of β-D-galactofuranosyl tri- and tetrasaccharides possessing diverse glycosidic linkages.
    >> More from SciFinder ®
    https://chemport.cas.org/services/resolver?origin=ACS&resolution=options&coi=1%3ACAS%3A528%3ADC%252BC2cXhslChsbzM&md5=9f31eeeb1174b0f278238066c3809c09
  28. 28
    Pragani, R.; Seeberger, P. H. Total Synthesis of the Bacteroides fragilis Zwitterionic Polysaccharide A1 Repeating Unit. J. Am. Chem. Soc. 2011, 133 (1), 102– 107,  DOI: 10.1021/ja1087375
    Google Scholar
    28
    Total synthesis of the Bacteroides fragilis zwitterionic polysaccharide A1 repeating unit
    Pragani, Rajan; Seeberger, Peter H.
    Journal of the American Chemical Society (2011), 133 (1), 102-107CODEN: JACSAT; ISSN:0002-7863. (American Chemical Society)
    Nearly all bacteria capsular polysaccharides are T-cell-independent antigens that do not promote Ig class switching from IgM to IgG nor memory responses. In contrast, Zwitterionic polysaccharides activate T-cell-dependent immune responses by major histo-compatibility complex class II presentation, a mechanism previously believed to be reserved for peptidic antigens. The best studied zwitterionic polysaccharide, polysaccharide A1 (PS A1) is found on the capsule of the commensal bacteria Bacteroides fragilis. Its potent immunomodulatory properties have been linked to postoperative intra-abdominal abscess formation. Here, we report the synthesis of the PS A1 tetrasaccharide repeating unit as a tool to investigate the biol. role of this polysaccharide. A modular synthetic strategy originating from the reducing end of the PS A1 repeating unit was unsuccessful and illustrated the limitations of glycosylation reactions between highly armed glycosylating agents and poor nucleophiles. Thus, a [3+1] glycosylation relying on trisaccharide and pyruvalated galactose was used to complete the first total synthesis of the PS A1 tetrasaccharide repeating unit.
    >> More from SciFinder ®
    https://chemport.cas.org/services/resolver?origin=ACS&resolution=options&coi=1%3ACAS%3A528%3ADC%252BC3cXhsFClu7%252FF&md5=7879aff750f7a75884dff4e935911594
  29. 29
    Yang, Y.; Martin, C. E.; Seeberger, P. H. Total synthesis of the core tetrasaccharide of Neisseria meningitidislipopolysaccharide, a potential vaccine candidate for meningococcal diseases. Chem. Sci. 2012, 3 (3), 896– 899,  DOI: 10.1039/C1SC00804H
    Google Scholar
    There is no corresponding record for this reference.
  30. 30
    Geissner, A.; Anish, C.; Seeberger, P. H. Glycan arrays as tools for infectious disease research. Curr. Opin. Chem. Biol. 2014, 18, 38– 45,  DOI: 10.1016/j.cbpa.2013.11.013
    Google Scholar
    30
    Glycan arrays as tools for infectious disease research
    Geissner, Andreas; Anish, Chakkumkal; Seeberger, Peter H.
    Current Opinion in Chemical Biology (2014), 18 (), 38-45CODEN: COCBF4; ISSN:1367-5931. (Elsevier B.V.)
    A review. Infectious diseases cause millions of deaths worldwide each year and are a major burden for economies, esp. in underdeveloped countries. Glycans and their interactions with other biomols. are involved in all major steps of infection. Glycan arrays enable the rapid and sensitive detection of those interactions and are among the most powerful techniques to study the mol. biol. of infectious diseases. This review will focus on recent developments and discuss the applications of glycan arrays to the elucidation of host-pathogen and pathogen-pathogen interactions, the development of tools for infection diagnosis and the use of glycan arrays in modern vaccine design.
    >> More from SciFinder ®
    https://chemport.cas.org/services/resolver?origin=ACS&resolution=options&coi=1%3ACAS%3A528%3ADC%252BC2cXivF2mtro%253D&md5=ee840ac9f7389bbcc00818f3b107f34d
  31. 31
    Geissner, A.; Seeberger, P. H. Glycan Arrays: From Basic Biochemical Research to Bioanalytical and Biomedical Applications. Annu. Rev. Anal. Chem. 2016, 9 (1), 223– 247,  DOI: 10.1146/annurev-anchem-071015-041641
    Google Scholar
    There is no corresponding record for this reference.
  32. 32
    Mazmanian, S. K.; Kasper, D. L. The love-hate relationship between bacterial polysaccharides and the host immune system. Nat. Rev. Immunol. 2006, 6 (11), 849– 858,  DOI: 10.1038/nri1956
    Google Scholar
    There is no corresponding record for this reference.
  33. 33
    Astronomo, R. D.; Burton, D. R. Carbohydrate vaccines: developing sweet solutions to sticky situations?. Nat. Rev. Drug Discovery 2010, 9 (4), 308– 324,  DOI: 10.1038/nrd3012
    Google Scholar
    33
    Carbohydrate vaccines: developing sweet solutions to sticky situations?
    Astronomo, Rena D.; Burton, Dennis R.
    Nature Reviews Drug Discovery (2010), 9 (4), 308-324CODEN: NRDDAG; ISSN:1474-1776. (Nature Publishing Group)
    A review. Recent technol. advances in glycobiol. and glycochem. are paving the way for a new era in carbohydrate vaccine design. This is enabling greater efficiency in the identification, synthesis and evaluation of unique glycan epitopes found on a plethora of pathogens and malignant cells. Here, the authors review the progress being made in addressing challenges posed by targeting the surface carbohydrates of bacteria, protozoa, helminths, viruses, fungi and cancer cells for vaccine purposes.
    >> More from SciFinder ®
    https://chemport.cas.org/services/resolver?origin=ACS&resolution=options&coi=1%3ACAS%3A528%3ADC%252BC3cXktVGjtL4%253D&md5=9cb458281569cdd0df3a044161cd8eea
  34. 34
    Avci, F. Y.; Li, X.; Tsuji, M.; Kasper, D. L. A mechanism for glycoconjugate vaccine activation of the adaptive immune system and its implications for vaccine design. Nat. Med. 2011, 17 (12), 1602– 1609,  DOI: 10.1038/nm.2535
    Google Scholar
    34
    A mechanism for glycoconjugate vaccine activation of the adaptive immune system and its implications for vaccine design
    Avci, Fikri Y.; Li, Xiangming; Tsuji, Moriya; Kasper, Dennis L.
    Nature Medicine (New York, NY, United States) (2011), 17 (12), 1602-1609CODEN: NAMEFI; ISSN:1078-8956. (Nature Publishing Group)
    Glycoconjugate vaccines have provided enormous health benefits globally, but they have been less successful in some populations at high risk for developing disease. To identify new approaches to enhancing glycoconjugate effectiveness, we investigated mol. and cellular mechanisms governing the immune response to a prototypical glycoconjugate vaccine. We found that in antigen-presenting cells a carbohydrate epitope is generated upon endolysosomal processing of group B streptococcal type III polysaccharide coupled to a carrier protein. In conjunction with a carrier protein-derived peptide, this carbohydrate epitope binds major histocompatibility class II (MHCII) and stimulates carbohydrate-specific CD4+ T cell clones to produce interleukins 2 and 4-cytokines essential for providing T cell help to antibody-producing B cells. An archetypical glycoconjugate vaccine that we constructed to maximize the presentation of carbohydrate-specific T cell epitopes is 50-100 times more potent and substantially more protective in a neonatal mouse model of group B Streptococcus infection than a vaccine constructed by methods currently used by the vaccine industry. Our discovery of how glycoconjugates are processed resulting in presentation of carbohydrate epitopes that stimulate CD4+ T cells has key implications for glycoconjugate vaccine design that could result in greatly enhanced vaccine efficacy.
    >> More from SciFinder ®
    https://chemport.cas.org/services/resolver?origin=ACS&resolution=options&coi=1%3ACAS%3A528%3ADC%252BC3MXhsV2gt7%252FL&md5=c02d36037865b38be13179ca1eb84fce
  35. 35
    Shinefield, H. R. Overview of the development and current use of CRM(197) conjugate vaccines for pediatric use. Vaccine 2010, 28 (27), 4335– 4339,  DOI: 10.1016/j.vaccine.2010.04.072
    Google Scholar
    There is no corresponding record for this reference.
  36. 36
    Esteves, P. J.; Abrantes, J.; Baldauf, H. M.; BenMohamed, L.; Chen, Y.; Christensen, N.; Gonzalez-Gallego, J.; Giacani, L.; Hu, J.; Kaplan, G. The wide utility of rabbits as models of human diseases. Exp. Mol. Med. 2018, 50 (5), 1– 10,  DOI: 10.1038/s12276-018-0094-1
    Google Scholar
    There is no corresponding record for this reference.
  37. 37
    Kaplonek, P.; Khan, N.; Reppe, K.; Schumann, B.; Emmadi, M.; Lisboa, M. P.; Xu, F. F.; Calow, A. D. J.; Parameswarappa, S. G.; Witzenrath, M. Improving vaccines against Streptococcus pneumoniae using synthetic glycans. Proc. Natl. Acad. Sci. U.S.A. 2018, 115 (52), 13353– 13358,  DOI: 10.1073/pnas.1811862115
    Google Scholar
    37
    Improving vaccines against Streptococcus pneumoniae using synthetic glycans
    Kaplonek, Paulina; Khan, Naeem; Reppe, Katrin; Schumann, Benjamin; Emmadi, Madhu; Lisboa, Marilda P.; Xu, Fei-Fei; Calow, Adam D. J.; Parameswarappa, Sharavathi G.; Witzenrath, Martin; Pereira, Claney L.; Seeberger, Peter H.
    Proceedings of the National Academy of Sciences of the United States of America (2018), 115 (52), 13353-13358CODEN: PNASA6; ISSN:0027-8424. (National Academy of Sciences)
    Streptococcus pneumoniae remains a deadly disease in small children and the elderly even though conjugate and polysaccharide vaccines based on isolated capsular polysaccharides (CPS) are successful. The most common serotypes that cause infection are used in vaccines around the world, but differences in geog. and demog. serotype distribution compromises protection by leading vaccines. The medicinal chem. approach to glycoconjugate vaccine development has helped to improve the stability and immunogenicity of synthetic vaccine candidates for several serotypes leading to the induction of higher levels of specific protective antibodies. Here, we show that marketed CPS-based glycoconjugate vaccines can be improved by adding synthetic glycoconjugates representing serotypes that are not covered by existing vaccines. Combination (coformulation) of synthetic glycoconjugates with the licensed vaccines Prevnar13 (13-valent) and Synflorix (10-valent) yields improved 15- and 13-valent conjugate vaccines, resp., in rabbits. A pentavalent semisynthetic glycoconjugate vaccine contg. five serotype antigens (sPCV5) elicits antibodies with strong in vitro opsonophagocytic activity. This study illustrates that synthetic oligosaccharides can be used in coformulation with both isolated polysaccharide glycoconjugates to expand protection from existing vaccines and each other to produce precisely defined multi-valent conjugated vaccines.
    >> More from SciFinder ®
    https://chemport.cas.org/services/resolver?origin=ACS&resolution=options&coi=1%3ACAS%3A528%3ADC%252BC1cXisF2rsrfE&md5=d84a363b169710f09461695053692e19
  38. 38
    Sanapala, S. R.; Seco, B. M. S.; Baek, J. Y.; Awan, S. I.; Pereira, C. L.; Seeberger, P. H. Chimeric oligosaccharide conjugate induces opsonic antibodies against Streptococcus pneumoniae serotypes 19A and 19F. Chem. Sci. 2020, 11 (28), 7401– 7407,  DOI: 10.1039/D0SC02230F
    Google Scholar
    38
    Chimeric oligosaccharide conjugate induces opsonic antibodies against Streptococcus pneumoniae serotypes 19A and 19F
    Sanapala, Someswara Rao; Seco, Bruna M. S.; Baek, Ju Yuel; Awan, Shahid I.; Pereira, Claney L.; Seeberger, Peter H.
    Chemical Science (2020), 11 (28), 7401-7407CODEN: CSHCCN; ISSN:2041-6520. (Royal Society of Chemistry)
    Streptococcus pneumoniae 19A (ST19A) and 19F (ST19F) are among the prevalent serotypes causing pneumococcal disease worldwide even after introduction of a 13-valent pneumococcal conjugate vaccine (PCV13). Synthetic glycoconjugate vaccines have defined chem. structures rather than isolated polysaccharide mixts. utilized in marketed vaccines. Ideally, a minimal no. of synthetic antigens would cover as many bacterial serotypes to lower cost of goods and minimize the response to carrier proteins. To demonstrate that a chimeric oligosaccharide antigen can induce a protective immune response against multiple serotypes, we synthesized a chimeric antigen (ST19AF) that is comprised of a repeating unit of ST19A and ST19F capsular polysaccharide each. Synthetic glycan epitopes representing only ST19A, and ST19F were prepd. for comparison. Semisynthetic glycoconjugates contg. chimeric antigen ST19AF induced high antibody titers able to recognize native CPS from ST19A and ST19F in rabbits. The antibodies were able to kill both strains of pneumococci. Chimeric antigens are an attractive means to induce an immune response against multiple bacterial serotypes.
    >> More from SciFinder ®
    https://chemport.cas.org/services/resolver?origin=ACS&resolution=options&coi=1%3ACAS%3A528%3ADC%252BB3cXht1OgtLvN&md5=4d1545e3b031c95777f819fb520e479e
  39. 39
    Rappuoli, R. Glycoconjugate vaccines: Principles and mechanisms. Sci. Transl. Med. 2018, 10 (456), eaat4615  DOI: 10.1126/scitranslmed.aat4615
    Google Scholar
    There is no corresponding record for this reference.
  40. 40
    Clarke, B. R.; Ovchinnikova, O. G.; Kelly, S. D.; Williamson, M. L.; Butler, J. E.; Liu, B.; Wang, L.; Gou, X.; Follador, R.; Lowary, T. L. Molecular basis for the structural diversity in serogroup O2-antigen polysaccharides in Klebsiella pneumoniae. J. Biol. Chem. 2018, 293 (13), 4666– 4679,  DOI: 10.1074/jbc.RA117.000646
    Google Scholar
    There is no corresponding record for this reference.
  41. 41
    Bulati, M.; Busa, R.; Carcione, C.; Iannolo, G.; Di Mento, G.; Cuscino, N.; Di Gesu, R.; Piccionello, A. P.; Buscemi, S.; Carreca, A. P. Klebsiella pneumoniae Lipopolysaccharides Serotype O2afg Induce Poor Inflammatory Immune Responses Ex Vivo. Microorganisms 2021, 9 (6), 1317,  DOI: 10.3390/microorganisms9061317
    Google Scholar
    There is no corresponding record for this reference.
  42. 42
    Peng, Z.; Wu, J.; Wang, K.; Li, X.; Sun, P.; Zhang, L.; Huang, J.; Liu, Y.; Hua, X.; Yu, Y. Production of a Promising Biosynthetic Self-Assembled Nanoconjugate Vaccine against Klebsiella Pneumoniae Serotype O2 in a General Escherichia Coli Host. Adv. Sci. 2021, 8 (14), e2100549  DOI: 10.1002/advs.202100549
    Google Scholar
    There is no corresponding record for this reference.
  43. 43
    Cohen, T. S.; Pelletier, M.; Cheng, L.; Pennini, M. E.; Bonnell, J.; Cvitkovic, R.; Chang, C. S.; Xiao, X.; Cameroni, E.; Corti, D. Anti-LPS antibodies protect against Klebsiella pneumoniae by empowering neutrophil-mediated clearance without neutralizing TLR4. JCI Insight 2017, 2 (9), e92774  DOI: 10.1172/jci.insight.92774
    Google Scholar
    There is no corresponding record for this reference.
  44. 44
    Avci, F. Y.; Li, X.; Tsuji, M.; Kasper, D. L. Carbohydrates and T cells: a sweet twosome. Semin. Immunol. 2013, 25 (2), 146– 151,  DOI: 10.1016/j.smim.2013.05.005
    Google Scholar
    44
    Carbohydrates and T cells: A sweet twosome
    Avci, Fikri Y.; Li, Xiangming; Tsuji, Moriya; Kasper, Dennis L.
    Seminars in Immunology (2013), 25 (2), 146-151CODEN: SEIME2; ISSN:1044-5323. (Elsevier Ltd.)
    A review. Carbohydrates as T cell-activating antigens have been generating significant interest. For many years, carbohydrates were thought of as T-independent antigens, however, more recent research had demonstrated that mono- or oligosaccharides glycosidically linked to peptides can be recognized by T cells. T cell recognition of these glycopeptides depends on the structure of both peptide and glycan portions of the antigen. Subsequently, it was discovered that natural killer T cells recognized glycolipids when presented by the antigen presenting mol. CD1d. A transformative insight into glycan-recognition by T cells occurred when zwitterionic polysaccharides were discovered to bind to and be presented by MHCII to CD4+ T cells. Based on this latter observation, the role that carbohydrate epitopes generated from glycoconjugate vaccines had in activating helper T cells was explored and it was found that these epitopes are presented to specific carbohydrate recognizing T cells through a unique mechanism. Here we review the key interactions between carbohydrate antigens and the adaptive immune system at the mol., cellular and systems levels exploring the significant biol. implications in health and disease.
    >> More from SciFinder ®
    https://chemport.cas.org/services/resolver?origin=ACS&resolution=options&coi=1%3ACAS%3A528%3ADC%252BC3sXptFGmtrs%253D&md5=f30ff826b12bbc6660cbb16cfaea834f
  45. 45
    Dwyer, M.; Gadjeva, M. Opsonophagocytic assay. Methods Mol. Biol. 2014, 1100, 373– 379,  DOI: 10.1007/978-1-62703-724-2_32
    Google Scholar
    There is no corresponding record for this reference.
  46. 46
    Burton, R. L.; Kim, H. W.; Lee, S.; Kim, H.; Seok, J. H.; Lee, S. H.; Balloch, A.; Licciardi, P.; Marimla, R.; Bae, S. Creation, characterization, and assignment of opsonic values for a new pneumococcal OPA calibration serum panel (Ewha QC sera panel A) for 13 serotypes. Medicine 2018, 97 (17), e0567  DOI: 10.1097/MD.0000000000010567
    Google Scholar
    There is no corresponding record for this reference.
  47. 47
    Jodar, L.; Butler, J.; Carlone, G.; Dagan, R.; Goldblatt, D.; Kayhty, H.; Klugman, K.; Plikaytis, B.; Siber, G.; Kohberger, R. Serological criteria for evaluation and licensure of new pneumococcal conjugate vaccine formulations for use in infants. Vaccine 2003, 21 (23), 3265– 3272,  DOI: 10.1016/S0264-410X(03)00230-5
    Google Scholar
    There is no corresponding record for this reference.
  48. 48
    Munford, R. S. Murine responses to endotoxin: another dirty little secret?. J. Infect. Dis. 2010, 201 (2), 175– 177,  DOI: 10.1086/649558
    Google Scholar
    48
    Murine responses to endotoxin: another dirty little secret?
    Munford Robert S
    The Journal of infectious diseases (2010), 201 (2), 175-7 ISSN:.
    There is no expanded citation for this reference.
    >> More from SciFinder ®
    https://chemport.cas.org/services/resolver?origin=ACS&resolution=options&coi=1%3ACAS%3A280%3ADC%252BD1MfksFWhuw%253D%253D&md5=5c38e3e4548faa548091ddca192ad8b1
  49. 49
    Reinhart, K.; Daniels, R.; Kissoon, N.; Machado, F. R.; Schachter, R. D.; Finfer, S. Recognizing Sepsis as a Global Health Priority - A WHO Resolution. N. Engl. J. Med. 2017, 377 (5), 414– 417,  DOI: 10.1056/NEJMp1707170
    Google Scholar
    There is no corresponding record for this reference.
  50. 50
    Haegens, A.; Vernooy, J. H.; Heeringa, P.; Mossman, B. T.; Wouters, E. F. Myeloperoxidase modulates lung epithelial responses to pro-inflammatory agents. Eur. Respir. J. 2008, 31 (2), 252– 260,  DOI: 10.1183/09031936.00029307
    Google Scholar
    There is no corresponding record for this reference.
  51. 51
    Matute-Bello, G.; Downey, G.; Moore, B. B.; Groshong, S. D.; Matthay, M. A.; Slutsky, A. S.; Kuebler, W. M. An Official American Thoracic Society Workshop Report: Features and Measurements of Experimental Acute Lung Injury in Animals. Am. J. Respir. Cell Mol. Biol. 2011, 44 (5), 725– 738,  DOI: 10.1165/rcmb.2009-0210ST
    Google Scholar
    51
    An official american thoracic society workshop report: features and measurements of experimental acute lung injury in animals
    Matute-Bello, Gustavo; Downey, Gregory; Moore, Bethany B.; Groshong, Steve D.; Matthay, Michael A.; Slutsky, Arthur S.; Kuebler, Wolfgang M.
    American Journal of Respiratory Cell and Molecular Biology (2011), 44 (5), 725-738CODEN: AJRBEL; ISSN:1044-1549. (American Thoracic Society)
    Acute lung injury (ALI) is well defined in humans, but there is no agreement as to the main features of acute lung injury in animal models. A Committee was organized to det. the main features that characterize ALI in animal models and to identify the most relevant methods to assess these features. We used a Delphi approach in which a series of questionnaires were distributed to a panel of experts in exptl. lung injury. The Committee concluded that the main features of exptl. ALI include histol. evidence of tissue injury, alteration of the alveolar capillary barrier, presence of an inflammatory response, and evidence of physiol. dysfunction; they recommended that, to det. if ALI has occurred, at least three of these four main features of ALI should be present. The Committee also identified key "very relevant" and "somewhat relevant" measurements for each of the main features of ALI and recommended the use of least one "very relevant" measurement and preferably one or two addnl. sep. measurements to det. if a main feature of ALI is present. Finally, the Committee emphasized that not all of the measurements listed can or should be performed in every study, and that measurements not included in the list are by no means "irrelevant.". Our list of features and measurements of ALI is intended as a guide for investigators, and ultimately investigators should choose the particular measurements that best suit the exptl. questions being addressed as well as take into consideration any unique aspects of the exptl. design.
    >> More from SciFinder ®
    https://chemport.cas.org/services/resolver?origin=ACS&resolution=options&coi=1%3ACAS%3A528%3ADC%252BC3MXot1Kjtr8%253D&md5=74e2c3187741c2fd5f3c0d8330bfef0e
  52. 52
    Klopfleisch, R. Multiparametric and semiquantitative scoring systems for the evaluation of mouse model histopathology--a systematic review. BMC Vet. Res. 2013, 9, 123,  DOI: 10.1186/1746-6148-9-123
    Google Scholar
    There is no corresponding record for this reference.
  53. 53
    West, J. B. Perivascular edema, a factor in pulmonary vascular resistance. Am. Heart J. 1965, 70 (4), 570– 572,  DOI: 10.1016/0002-8703(65)90370-4
    Google Scholar
    There is no corresponding record for this reference.
  54. 54
    Fein, A. M.; Calalang-Colucci, M. G. Acute lung injury and acute respiratory distress syndrome in sepsis and septic shock. Crit. Care Clin. 2000, 16 (2), 289– 317,  DOI: 10.1016/S0749-0704(05)70111-1
    Google Scholar
    There is no corresponding record for this reference.
  55. 55
    Kumar, V.; Chhibber, S. Acute lung inflammation in Klebsiella pneumoniae B5055-induced pneumonia and sepsis in BALB/c mice: a comparative study. Inflammation 2011, 34 (5), 452– 462,  DOI: 10.1007/s10753-010-9253-9
    Google Scholar
    There is no corresponding record for this reference.
  56. 56
    Dickerhof, N.; Huang, J.; Min, E.; Michaelsson, E.; Lindstedt, E. L.; Pearson, J. F.; Kettle, A. J.; Day, B. J. Myeloperoxidase inhibition decreases morbidity and oxidative stress in mice with cystic fibrosis-like lung inflammation. Free Radic. Biol. Med. 2020, 152, 91– 99,  DOI: 10.1016/j.freeradbiomed.2020.03.001
    Google Scholar
    There is no corresponding record for this reference.
  57. 57
    Sugamata, R.; Dobashi, H.; Nagao, T.; Yamamoto, K.; Nakajima, N.; Sato, Y.; Aratani, Y.; Oshima, M.; Sata, T.; Kobayashi, K. Contribution of neutrophil-derived myeloperoxidase in the early phase of fulminant acute respiratory distress syndrome induced by influenza virus infection. Microbiol. Immunol. 2012, 56 (3), 171– 182,  DOI: 10.1111/j.1348-0421.2011.00424.x
    Google Scholar
    There is no corresponding record for this reference.
  58. 58
    Saikam, V.; Dara, S.; Yadav, M.; Singh, P. P.; Vishwakarma, R. A. Dimethyltin Dichloride Catalyzed Regioselective Alkylation of cis-1,2-Diols at Room Temperature. J. Org. Chem. 2015, 80 (24), 11916– 11925,  DOI: 10.1021/acs.joc.5b01898
    Google Scholar
    There is no corresponding record for this reference.
  59. 59
    Deng, L. M.; Liu, X.; Liang, X. Y.; Yang, J. S. Regioselective glycosylation method using partially protected arabino- and galactofuranosyl thioglycosides as key glycosylating substrates and its application to one-pot synthesis of oligofuranoses. J. Org. Chem. 2012, 77 (7), 3025– 3037,  DOI: 10.1021/jo300084g
    Google Scholar
    59
    Regioselective Glycosylation Method Using Partially Protected Arabino- and Galactofuranosyl Thioglycosides as Key Glycosylating Substrates and Its Application to One-Pot Synthesis of Oligofuranoses
    Deng, Li-Min; Liu, Xia; Liang, Xing-Yong; Yang, Jin-Song
    Journal of Organic Chemistry (2012), 77 (7), 3025-3037CODEN: JOCEAH; ISSN:0022-3263. (American Chemical Society)
    We describe in this paper the development of a novel regioselective furanosylation methodol. using partially protected furanosyl thioglycosides as central glycosylating building blocks and its application in the efficient one-pot synthesis of a series of linear and branched-type arabino- and galactofuranoside fragments structurally related to the cell wall polysaccharides of Mycobacterium tuberculosis, Streptococcus pneumoniae sero-stype 35A, and sugar beet.
    >> More from SciFinder ®
    https://chemport.cas.org/services/resolver?origin=ACS&resolution=options&coi=1%3ACAS%3A528%3ADC%252BC38XivVOht7g%253D&md5=58eef1614a5179098045298ca80977ff
  60. 60
    Wu, X.; Ling, C. C.; Bundle, D. R. A new homobifunctional p-nitro phenyl ester coupling reagent for the preparation of neoglycoproteins. Org. Lett. 2004, 6 (24), 4407– 4410,  DOI: 10.1021/ol048614m
    Google Scholar
    60
    A New Homobifunctional p-Nitro Phenyl Ester Coupling Reagent for the Preparation of Neoglycoproteins
    Wu, Xiangyang; Ling, Chang-Chun; Bundle, David R.
    Organic Letters (2004), 6 (24), 4407-4410CODEN: ORLEF7; ISSN:1523-7060. (American Chemical Society)
    A new linker system has been designed and applied to neoglycoprotein synthesis. Reaction of oligosaccharide ω-aminoalkyl glycosides with homobifunctional adipic acid p-nitrophenyl diesters in dry DMF gave the corresponding amide half ester in good yields and of sufficient stability to permit chromatog. purifn. Subsequent conjugation with bovine serum albumin under very mild conditions afforded the corresponding neoglycoproteins with good efficiency. The method is well suited for the coupling of very small amts. (mg) of oligosaccharide and protein.
    >> More from SciFinder ®
    https://chemport.cas.org/services/resolver?origin=ACS&resolution=options&coi=1%3ACAS%3A528%3ADC%252BD2cXovFSlsLY%253D&md5=60840ed71db1cda743aa29010fb227cb
  61. 61
    Moor, K.; Fadlallah, J.; Toska, A.; Sterlin, D.; Balmer, M. L.; Macpherson, A. J.; Gorochov, G.; Larsen, M.; Slack, E. Analysis of bacterial-surface-specific antibodies in body fluids using bacterial flow cytometry. Nat. Protoc. 2016, 11 (8), 1531– 1553,  DOI: 10.1038/nprot.2016.091
    Google Scholar
    61
    Analysis of bacterial-surface-specific antibodies in body fluids using bacterial flow cytometry
    Moor Kathrin; Toska Albulena; Slack Emma; Fadlallah Jehane; Sterlin Delphine; Gorochov Guy; Larsen Martin; Balmer Maria L; Macpherson Andrew J; Balmer Maria L; Gorochov Guy; Larsen Martin
    Nature protocols (2016), 11 (8), 1531-53 ISSN:.
    Antibacterial antibody responses that target surfaces of live bacteria or secreted toxins are likely to be relevant in controlling bacterial pathogenesis. The ability to specifically quantify bacterial-surface-binding antibodies is therefore highly attractive as a quantitative correlate of immune protection. Here, binding of antibodies from various body fluids to pure-cultured live bacteria is made visible with fluorophore-conjugated secondary antibodies and measured by flow cytometry. We indicate the necessary controls for excluding nonspecific binding and also demonstrate a cross-adsorption technique for determining the extent of cross-reactivity. This technique has numerous advantages over standard ELISA and western blotting techniques because of its independence from scaffold binding, exclusion of cross-reactive elements from lysed bacteria and ability to visualize bacterial subpopulations. In addition, less than 10(5) bacteria and less than 10 μg of antibody are required per sample. The technique requires 3-4 h of hands-on experimentation and analysis. Moreover, it can be combined with automation and mutliplexing for high-throughput applications.
    >> More from SciFinder ®
    https://chemport.cas.org/services/resolver?origin=ACS&resolution=options&coi=1%3ACAS%3A280%3ADC%252BC2s3ls1CltQ%253D%253D&md5=123a8e137f962c18aa5fb75bec0255b6
  62. 62
    Burton, R. L.; Nahm, M. H. Development and validation of a fourfold multiplexed opsonization assay (MOPA4) for pneumococcal antibodies. Clin. Vaccine Immunol. 2006, 13 (9), 1004– 1009,  DOI: 10.1128/CVI.00112-06
    Google Scholar
    62
    Development and validation of a fourfold multiplexed opsonization assay (MOPA4) for pneumococcal antibodies
    Burton, Robert L.; Nahm, Moon H.
    Clinical and Vaccine Immunology (2006), 13 (9), 1004-1009CODEN: CVILA6; ISSN:1556-6811. (American Society for Microbiology)
    Opsonophagocytic killing assays (OPAs) are essential for developing and improving pneumococcal vaccines. There is a need for a high-throughput, reliable, standardized, and fully characterized OPA for pneumococcal antibodies. To meet the need, the authors have developed and characterized a fourfold multiplexed OPA (MOPA4) against 13 serotypes (1, 3, 4, 5, 6A, 6B, 7F, 9V, 14, 18C, 19A, 19F, and 23F) of pneumococci. Thirteen target bacteria were made resistant to only one of the following antibiotics: optochin, streptomycin, spectinomycin, and trimethoprim. Following optimization of assay conditions, accuracy of MOPA4 was detd. by testing 30 sera from old adults in the MOPA4 and the single-serotype assays. The opsonization titers obtained with both assays agreed well (r2 > 0.95). Although 22 (out of 390; ∼6%) results differed more than twofold, the differences were not reproducible. The assay was specific: preabsorbing test sera with homologous polysaccharide (PS) completely abrogated opsonic activity, but a pool of unrelated PS (5 μg/mL of each) had no effect. Intra- and interassay coeffs. of variation were 10 and 22%, resp. MOPA4 results were unaffected by having different target pneumococcal serotypes in each assay group. Also, HL60 cell-to-bacteria ratios could be varied twofold without affecting the results. The authors conclude that MOPA4 is sensitive, accurate, specific, precise, and robust enough for large-scale clin. studies. Furthermore, MOPA4 should allow evaluation of multivalent pneumococcal vaccines with the limited vol. of serum typically available from young children.
    >> More from SciFinder ®
    https://chemport.cas.org/services/resolver?origin=ACS&resolution=options&coi=1%3ACAS%3A528%3ADC%252BD28XhtVWgt73L&md5=2de17f60d8defbb969318a81b730c460
  63. 63
    Szijarto, V.; Guachalla, L. M.; Hartl, K.; Varga, C.; Banerjee, P.; Stojkovic, K.; Kaszowska, M.; Nagy, E.; Lukasiewicz, J.; Nagy, G. Both clades of the epidemic KPC-producing Klebsiella pneumoniae clone ST258 share a modified galactan O-antigen type. Int. J. Med. Microbiol. 2016, 306 (2), 89– 98,  DOI: 10.1016/j.ijmm.2015.12.002
    Google Scholar
    There is no corresponding record for this reference.

Cited By

Click to copy section linkSection link copied!

This article has not yet been cited by other publications.

Download PDF
Go to Journal of the American Chemical Society
Get e-Alerts
Get e-Alerts

Journal of the American Chemical Society

Cite this: J. Am. Chem. Soc. 2024, 146, 51, 35356–35366
Click to copy citationCitation copied!
https://doi.org/10.1021/jacs.4c13972
Published December 12, 2024

Copyright © 2024 The Authors. Published by American Chemical Society. This publication is licensed under

CC-BY 4.0 .

Article Views

2070

Altmetric

-

Citations

-
Learn about these metrics

Article Views are the COUNTER-compliant sum of full text article downloads since November 2008 (both PDF and HTML) across all institutions and individuals. These metrics are regularly updated to reflect usage leading up to the last few days.

Citations are the number of other articles citing this article, calculated by Crossref and updated daily. Find more information about Crossref citation counts.

The Altmetric Attention Score is a quantitative measure of the attention that a research article has received online. Clicking on the donut icon will load a page at altmetric.com with additional details about the score and the social media presence for the given article. Find more information on the Altmetric Attention Score and how the score is calculated.

  • Abstract

    High Resolution Image
    Download MS PowerPoint Slide

    Figure 1

    Figure 1. Glycoconjugate vaccine design and retro-synthetic analysis to obtain the epitopes. (A) Trisaccharide repeating unit of Gal-III from KPST258. (B) Synthetic trisaccharide repeating unit 1 and hexasaccharide 2 containing two repeating units, each connected to an amine linker. (C) Retrosynthetic analysis of trisaccharide 1 and hexasaccharide 2.

    High Resolution Image
    Download MS PowerPoint Slide

    Scheme 1

    Scheme 1. Synthesis of Trisaccharide 1 and Hexasaccharide 2: (A) Assembly of Protected Trisaccharide 3: (B) Global Deprotection of 3a
    High Resolution Image
    Download MS PowerPoint Slide

    aGalactofuranose partially cleaved during Pd catalyzed hydrogenation. With one-pot Birch reduction, trisaccharide 1 was obtained without cleavage of the Galf residue. (C) Synthesis of the modified galactofuranose building block 17. (D) Assembly of trisaccharide fragments 9 and 10 for the assembly of hexasaccharide target 2.

    Figure 2

    Figure 2. Determination of human antibody binding to synthetic O-antigens derived from O2afg serotype. (A) Synthetic glycans 1 and 2 were immobilized on a glass slide and sera from CRK-Kp infected patients, and healthy human were incubated with the antigens. Antibody binding was determined by using a glycan microarray assay, and the fluorescence intensity indicates the number of bound IgG antibodies. (B) Graphs showed the titer of bound human IgG antibodies to either O2afg trisaccharide 1 (on the left) or the hexasaccharide 2 (on the right). Both antigens showed positive antibody binders, but only the hexasaccharide showed a significant increase in fluorescence intensity, when compared to the negative control group. A trisaccharide containing the 6-deoxy hexose l-rhamnose (Rha) was used as human antibody positive control. The analysis was performed using the unpaired t-test of individual serum mean values from triplicate printed glycan spots. CRKP─carbapenem-resistant K. pneumoniae, MFI─mean fluorescence intensity in human sera evaluated by glycan array (left panel), and the mean fluorescence intensity of bound antibodies to O2afg synthetic hexasaccharide from different groups was compared (graph on the right). The sera at time point 0 h was collected as control of preinfection. Two-way ANOVA was used in the analysis. The data represent the mean of MFI values from triplicated printed spots of three individuals per group ±95% CI. **p < 0.01.

    High Resolution Image
    Download MS PowerPoint Slide

    Figure 3

    Figure 3. Rabbits immunized with CRM197-2 produce antibodies that recognize both LPS epitopes 1 and 2. (A) Schematic schedule for rabbit immunization. Five individuals were immunized on day 0 with CRM197-2 (1 μg antigen per dose) formulated in alum and boosted on days 14 and 28 with the same formulation. The long-term immune response was measured 11 days after a boost injection on day 133. Negative control group containing three individuals received PBS with alum. (B) Levels of IgG specific to the hexasaccharide 2. (C) Levels of IgG specific against the trisaccharide 1. (D) Levels of IgA specific to the hexasaccharide 2. (E) Levels of IgA specific antibody against the trisaccharide 1. The data represent the 95% CI distribution of five animals in the CRM197-2 group and three animals in the PBS group. Two-way ANOVA was used for statistical analysis. MFI─mean fluorescence intensity measured by ELISA. *p < 0.05 and **p < 0.01.

    High Resolution Image
    Download MS PowerPoint Slide

    Figure 4

    Figure 4. Rabbit anti-O2afg IgG binding assay measured by flow cytometry and opsonophagocytic killing activity. (A,B) K. pneumoniae O2afg or O1 were incubated with sera from day 35 (diluted 1:100) from rabbits immunized with either glycoconjugate (CRM197-2 group, red) or PBS (PBS group, blue). A negative control containing bacteria with fluorescent secondary antibody was used as reference to establish the threshold for positive binding (Figure S4). The positive bind quantification shown in the right panel (MFI) was based on the product of the percent of gated events that passed the fluorescence threshold and the median fluorescence of those events that passed the threshold. MFI─mean fluorescence intensity, K. pn─K. pneumoniae. The error bars represent the SD of three independent experiments. One-way ANOVA was used for statistical analysis. **p < 0.01. (C–H) Killing activity of antibodies present in the sera of rabbits was evaluated with K. pneumoniae expressing a capsule (C,D) and a mutant strain without capsule (F,G). The opsonic index represents the sera dilution for 50% of bacteria killing (E,H) and was based on a four-parameter linear regression of sera dilution curves from two independent assays performed in duplicate. The percentage bacterial killing data (D,G) were mean ± SD of colony-forming units (CFUs) reduction relative to negative control (sample lacking sera with complement and effector cells) of two independent assays performed in duplicate. Unpaired t-test was used in the analysis. *p < 0.05, **p < 0.01.

    High Resolution Image
    Download MS PowerPoint Slide

    Figure 5

    Figure 5. Passive immunization in a murine pneumonia model. (A) Mice were intranasally infected with 1 × 108 of O2afg-CR-Kp, and 2 h later passively immunized with polyclonal sera of rabbits vaccinated with either synthetic anti-O2afg vaccine (CRM197-2) or PBS vaccine (PBS). Lung, BALF, and blood were collected 48 h postinfection. Mice infected with PBS (PBSinf) but receiving CRM197-2 polyclonal rabbit sera were used as negative control. (B) Lung (left), BALF (middle), and blood (right) were collected 48 h postinfection and analyzed for bacterial burden by quantifying CFU counting. (C) Myeloperoxidase (MPO) activity and lung permeability were measured in BALF of mice infected with CR-Kp 48 h postinfection. Levels of MPO was measured by its enzymatic activity against TMB substrate. Lung permeability was measured by the amount of total protein present in BALF. The data represent the mean ± SE of 12 mice per group. Mann–Whitney was used for the statistical analysis. **p < 0.01 and ****p < 0.0001. One mouse was excluded from the Kpn-infected PBS group due to death after narcosis, and one mouse outlier was excluded from the CR-Kp-infected CRM197-2 group. (D) Lung sections stained with hematoxylin and eosin (H&E) from mice noninfected (PBSInf), mice infected and treated with polyclonal sera of rabbits immunized with O2afg vaccine (Kpn + CRM197-2), and mice infected and treated with polyclonal of rabbits vaccinated with PBS (Kpn + PBS), 48 h postinfection. (E) Histopathology scores of the lungs of mice. From left to right: total cells in lungs; inflammation score of lungs; alveolar edema of lungs; and perivascular edema of lungs. The data represent the mean ± SE of five mice per group. Kruskal–Wallis was used for the statistical analysis. *p < 0.05 and **p < 0.01.

    High Resolution Image
    Download MS PowerPoint Slide

  • References

    This article references 63 other publications.

    1. 1
      Li, B.; Zhao, Y.; Liu, C.; Chen, Z.; Zhou, D. Molecular pathogenesis of Klebsiella pneumoniae. Future Microbiol. 2014, 9 (9), 1071– 1081,  DOI: 10.2217/fmb.14.48
      There is no corresponding record for this reference.
    2. 2
      Global Report on Infection Prevention and Control; World Health Organization, 2022.
      There is no corresponding record for this reference.
    3. 3
      Lou, T.; Du, X.; Zhang, P.; Shi, Q.; Han, X.; Lan, P.; Yan, R.; Hu, H.; Wang, Y.; Wu, X. Risk factors for infection and mortality caused by carbapenem-resistant Klebsiella pneumoniae: A large multicentre case-control and cohort study. J. Infect. 2022, 84 (5), 637– 647,  DOI: 10.1016/j.jinf.2022.03.010
      There is no corresponding record for this reference.
    4. 4
      Antibiotic resistance threats in the United States, 2019; Centers for Disease Control and Prevention (U.S.); National Center for Emerging Zoonotic and Infectious Diseases (U.S.). Division of Healthcare Quality Promotion. Antibiotic Resistance Coordination and Strategy Unit., 2019.
      There is no corresponding record for this reference.
    5. 5
      Marsh, J. W.; Mustapha, M. M.; Griffith, M. P.; Evans, D. R.; Ezeonwuka, C.; Pasculle, A. W.; Shutt, K. A.; Sundermann, A.; Ayres, A. M.; Shields, R. K. Evolution of Outbreak-Causing Carbapenem-Resistant Klebsiella pneumoniae ST258 at a Tertiary Care Hospital over 8 Years. mBio 2019, 10 (5), e01945  DOI: 10.1128/mbio.01945-19
      There is no corresponding record for this reference.
    6. 6
      Munoz-Price, L. S.; Poirel, L.; Bonomo, R. A.; Schwaber, M. J.; Daikos, G. L.; Cormican, M.; Cornaglia, G.; Garau, J.; Gniadkowski, M.; Hayden, M. K. Clinical epidemiology of the global expansion of Klebsiella pneumoniae carbapenemases. Lancet Infect. Dis. 2013, 13 (9), 785– 796,  DOI: 10.1016/S1473-3099(13)70190-7
      6
      Clinical epidemiology of the global expansion of Klebsiella pneumoniae carbapenemases
      Munoz-Price L Silvia; Poirel Laurent; Bonomo Robert A; Schwaber Mitchell J; Daikos George L; Cormican Martin; Cornaglia Giuseppe; Garau Javier; Gniadkowski Marek; Hayden Mary K; Kumarasamy Karthikeyan; Livermore David M; Maya Juan J; Nordmann Patrice; Patel Jean B; Paterson David L; Pitout Johann; Villegas Maria Virginia; Wang Hui; Woodford Neil; Quinn John P
      The Lancet. Infectious diseases (2013), 13 (9), 785-96 ISSN:.
      Klebsiella pneumoniae carbapenemases (KPCs) were originally identified in the USA in 1996. Since then, these versatile β-lactamases have spread internationally among Gram-negative bacteria, especially K pneumoniae, although their precise epidemiology is diverse across countries and regions. The mortality described among patients infected with organisms positive for KPC is high, perhaps as a result of the limited antibiotic options remaining (often colistin, tigecycline, or aminoglycosides). Triple drug combinations using colistin, tigecycline, and imipenem have recently been associated with improved survival among patients with bacteraemia. In this Review, we summarise the epidemiology of KPCs across continents, and discuss issues around detection, present antibiotic options and those in development, treatment outcome and mortality, and infection control. In view of the limitations of present treatments and the paucity of new drugs in the pipeline, infection control must be our primary defence for now.
      >> More from SciFinder ®
      https://chemport.cas.org/services/resolver?origin=ACS&resolution=options&coi=1%3ACAS%3A280%3ADC%252BC3sbitFGktQ%253D%253D&md5=0491bc8ae393c42130affd6ddfdc4063
    7. 7
      Wang, M.; Earley, M.; Chen, L.; Hanson, B. M.; Yu, Y.; Liu, Z.; Salcedo, S.; Cober, E.; Li, L.; Kanj, S. S. Clinical outcomes and bacterial characteristics of carbapenem-resistant Klebsiella pneumoniae complex among patients from different global regions (CRACKLE-2): a prospective, multicentre, cohort study. Lancet Infect. Dis. 2022, 22 (3), 401– 412,  DOI: 10.1016/S1473-3099(21)00399-6
      There is no corresponding record for this reference.
    8. 8
      van Duin, D.; Arias, C. A.; Komarow, L.; Chen, L.; Hanson, B. M.; Weston, G.; Cober, E.; Garner, O. B.; Jacob, J. T.; Satlin, M. J. Molecular and clinical epidemiology of carbapenem-resistant Enterobacterales in the USA (CRACKLE-2): a prospective cohort study. Lancet Infect. Dis. 2020, 20 (6), 731– 741,  DOI: 10.1016/S1473-3099(19)30755-8
      There is no corresponding record for this reference.
    9. 9
      Choi, M.; Hegerle, N.; Nkeze, J.; Sen, S.; Jamindar, S.; Nasrin, S.; Sen, S.; Permala-Booth, J.; Sinclair, J.; Tapia, M. D. The Diversity of Lipopolysaccharide (O) and Capsular Polysaccharide (K) Antigens of Invasive Klebsiella pneumoniae in a Multi-Country Collection. Front. Microbiol. 2020, 11, 1249,  DOI: 10.3389/fmicb.2020.01249
      9
      The Diversity of Lipopolysaccharide (O) and Capsular Polysaccharide (K) Antigens of Invasive Klebsiella pneumoniae in a Multi-Country Collection
      Choi Myeongjin; Hegerle Nicolas; Nkeze Joseph; Sen Shaichi; Jamindar Sanchita; Nasrin Shamima; Sen Sunil; Permala-Booth Jasnehta; Sinclair James; Tapia Milagritos D; Simon Raphael; Cross Alan S; Tennant Sharon M; Choi Myeongjin; Hegerle Nicolas; Nkeze Joseph; Sen Shaichi; Jamindar Sanchita; Nasrin Shamima; Sen Sunil; Permala-Booth Jasnehta; Sinclair James; Simon Raphael; Cross Alan S; Tennant Sharon M; Tapia Milagritos D; Johnson J Kristie; Mamadou Sylla; Thaden Joshua T; Fowler Vance G Jr; Fowler Vance G Jr; Aguilar Ana; Teran Enrique; Decre Dominique; Morel Florence; Krogfelt Karen Angeliki; Brauner Annelie; Protonotariou Efthymia; Christaki Eirini; Christaki Eirini; Shindo Yuichiro; Lin Yi-Tsung; Lin Yi-Tsung; Kwa Andrea L; Kwa Andrea L; Kwa Andrea L; Shakoor Sadia; Singh-Moodley Ashika; Perovic Olga; Jacobs Jan; Jacobs Jan; Lunguya Octavie
      Frontiers in microbiology (2020), 11 (), 1249 ISSN:1664-302X.
      Klebsiella pneumoniae is a common cause of sepsis and is particularly associated with healthcare-associated infections. New strategies are needed to prevent or treat infections due to the emergence of multi-drug resistant K. pneumoniae. The goal of this study was to determine the diversity and distribution of O (lipopolysaccharide) and K (capsular polysaccharide) antigens on a large (>500) global collection of K. pneumoniae strains isolated from blood to inform vaccine development efforts. A total of 645 K. pneumoniae isolates were collected from the blood of patients in 13 countries during 2005-2017. Antibiotic susceptibility was determined using the Kirby-Bauer disk diffusion method. O antigen types including the presence of modified O galactan types were determined by PCR. K types were determined by multiplex PCR and wzi capsular typing. Sequence types of isolates were determined by multilocus sequence typing (MLST) targeting seven housekeeping genes. Among 591 isolates tested for antimicrobial resistance, we observed that 19.3% of isolates were non-susceptible to carbapenems and 62.1% of isolates were multidrug resistant (from as low as 16% in Sweden to 94% in Pakistan). Among 645 isolates, four serotypes, O1, O2, O3, and O5, accounted for 90.1% of K. pneumoniae strains. Serotype O1 was associated with multidrug resistance. Fifty percent of 199 tested O1 and O2 strains were gmlABC-positive, indicating the presence of the modified polysaccharide subunit D-galactan III. The most common K type was K2 by both multiplex PCR and wzi capsular typing. Of 39 strains tested by MLST, 36 strains were assigned to 26 known sequence types of which ST14, ST25, and ST258 were the most common. Given the limited number of O antigen types, diverse K antigen types and the high multidrug resistance, we believe that an O antigen-based vaccine would offer an excellent prophylactic strategy to prevent K. pneumoniae invasive infection.
      >> More from SciFinder ®
      https://chemport.cas.org/services/resolver?origin=ACS&resolution=options&coi=1%3ACAS%3A280%3ADC%252BB38nls1Snug%253D%253D&md5=4d3e3785ff7b236a2d2095d3cf8f1801
    10. 10
      Follador, R.; Heinz, E.; Wyres, K. L.; Ellington, M. J.; Kowarik, M.; Holt, K. E.; Thomson, N. R. The diversity of Klebsiella pneumoniae surface polysaccharides. Microb. Genomes 2016, 2 (8), e000073  DOI: 10.1099/mgen.0.000073
      There is no corresponding record for this reference.
    11. 11
      Hsieh, P. F.; Lin, T. L.; Yang, F. L.; Wu, M. C.; Pan, Y. J.; Wu, S. H.; Wang, J. T. Lipopolysaccharide O1 antigen contributes to the virulence in Klebsiella pneumoniae causing pyogenic liver abscess. PLoS One 2012, 7 (3), e33155  DOI: 10.1371/journal.pone.0033155
      There is no corresponding record for this reference.
    12. 12
      Opoku-Temeng, C.; Kobayashi, S. D.; DeLeo, F. R. Klebsiella pneumoniae capsule polysaccharide as a target for therapeutics and vaccines. Comput. Struct. Biotechnol. J. 2019, 17, 1360– 1366,  DOI: 10.1016/j.csbj.2019.09.011
      12
      Klebsiella pneumoniae capsule polysaccharide as a target for therapeutics and vaccines
      Opoku-Temeng, Clement; Kobayashi, Scott D.; DeLeo, Frank R.
      Computational and Structural Biotechnology Journal (2019), 17 (), 1360-1366CODEN: CSBJAC; ISSN:2001-0370. (Elsevier B.V.)
      A review. Carbapenem-resistant (CR) Klebsiella pneumoniae has emerged as an urgent public health threat in many industrialized countries worldwide, including the United States. Infections caused by CR K. pneumoniae are difficult to treat because these organisms are typically resistant to multiple antibiotics, and the patients have significant comorbidities. Notably, there is high (∼50%) mortality among individuals with bacteremia caused by CR K. pneumoniae. Given the dearth of new antibiotics, and the recent convergence of multidrug resistance and hypervirulence, there is a crit. need for alternative strategies for the treatment of CR K. pneumoniae infections. The capsule polysaccharide (CPS) of K. pneumoniae has long been viewed as an important virulence factor that promotes resistance to phagocytosis and serum bactericidal activity. Thus, the CPS has been targeted previously for the development of therapeutics and vaccines, although there is no licensed CPS-based vaccine or therapy for the treatment of CR K. pneumoniae infections. Here, we discuss immunoprophylactic and immunotherapeutic approaches that have been tested previously for the treatment of Klebsiella infections. We also suggest potential strategies to promote development of CPS-based vaccines and therapies for prevention and treatment of CR K. pneumoniae infections.
      >> More from SciFinder ®
      https://chemport.cas.org/services/resolver?origin=ACS&resolution=options&coi=1%3ACAS%3A528%3ADC%252BC1MXitFOrtbjL&md5=53ffb2dd28430a9cb1bd7a8f966781fd
    13. 13
      Choi, M.; Tennant, S. M.; Simon, R.; Cross, A. S. Progress towards the development of Klebsiella vaccines. Expert Rev. Vaccines 2019, 18 (7), 681– 691,  DOI: 10.1080/14760584.2019.1635460
      There is no corresponding record for this reference.
    14. 14
      Wyres, K. L.; Wick, R. R.; Gorrie, C.; Jenney, A.; Follador, R.; Thomson, N. R.; Holt, K. E. Identification of Klebsiella capsule synthesis loci from whole genome data. Microb. Genomes 2016, 2 (12), e000102  DOI: 10.1099/mgen.0.000102
      There is no corresponding record for this reference.
    15. 15
      Artyszuk, D.; Jachymek, W.; Izdebski, R.; Gniadkowski, M.; Lukasiewicz, J. The OL101 O antigen locus specifies a novel Klebsiella pneumoniae serotype O13 structure. Carbohydr. Polym. 2024, 326, 121581,  DOI: 10.1016/j.carbpol.2023.121581
      There is no corresponding record for this reference.
    16. 16
      Stojkovic, K.; Szijarto, V.; Kaszowska, M.; Niedziela, T.; Hartl, K.; Nagy, G.; Lukasiewicz, J. Identification of d-Galactan-III As Part of the Lipopolysaccharide of Klebsiella pneumoniae Serotype O1. Front. Microbiol. 2017, 8, 684,  DOI: 10.3389/fmicb.2017.00684
      There is no corresponding record for this reference.
    17. 17
      Fang, C. T.; Shih, Y. J.; Cheong, C. M.; Yi, W. C. Rapid and Accurate Determination of Lipopolysaccharide O-Antigen Types in Klebsiella pneumoniae with a Novel PCR-Based O-Genotyping Method. J. Clin. Microbiol. 2016, 54 (3), 666– 675,  DOI: 10.1128/JCM.02494-15
      There is no corresponding record for this reference.
    18. 18
      Pennini, M. E.; De Marco, A.; Pelletier, M.; Bonnell, J.; Cvitkovic, R.; Beltramello, M.; Cameroni, E.; Bianchi, S.; Zatta, F.; Zhao, W. Immune stealth-driven O2 serotype prevalence and potential for therapeutic antibodies against multidrug resistant Klebsiella pneumoniae. Nat. Commun. 2017, 8 (1), 1991,  DOI: 10.1038/s41467-017-02223-7
      There is no corresponding record for this reference.
    19. 19
      Mohan, V. K.; Varanasi, V.; Singh, A.; Pasetti, M. F.; Levine, M. M.; Venkatesan, R.; Ella, K. M. Safety and immunogenicity of a Vi polysaccharide-tetanus toxoid conjugate vaccine (Typbar-TCV) in healthy infants, children, and adults in typhoid endemic areas: a multicenter, 2-cohort, open-label, double-blind, randomized controlled phase 3 study. Clin. Infect. Dis. 2015, 61 (3), 393– 402,  DOI: 10.1093/cid/civ295
      19
      Safety and immunogenicity of a Vi polysaccharide-tetanus toxoid conjugate vaccine (Typbar-TCV) in healthy infants, children, and adults in typhoid endemic areas: a multicenter, 2-cohort, open-label, double-blind, randomized controlled phase 3 study
      Mohan, Vadrevu Krishna; Varanasi, Vineeth; Singh, Anit; Pasetti, Marcela F.; Levine, Myron M.; Venkatesan, Ramasamy; Ella, Krishna M.
      Clinical Infectious Diseases (2015), 61 (3), 393-402CODEN: CIDIEL; ISSN:1058-4838. (Oxford University Press)
      Background: Enteric fever caused by Salmonella Typhi remains a major public health problem in developing countries. Typbar-TCV is a single-dose typhoid Vi polysaccharide-tetanus toxoid conjugate vaccine for persons≥6 mo of age. Methods: Six hundred fifty-four healthy subjects aged 2-45 years enrolled in a double-blind, randomized controlled trial (RCT) received a single dose of Typbar-TCV or comparator "Vi polysaccharide" (Typbar), and 327 healthy subjects aged 6-23 mo received a single dose of Typbar-TCV in an open-label trial (OLT); both received single-or multidose presentations from different lots. After 2 years, subsets in each group received a booster dose. The primary objective included anal. of geometric mean titer (GMTs) and 4-fold rise of anti-Vi serum IgG (IgG) ELISA titers over baseline (seroconversion [SCN]) 42 days after immunization. Results: Typbar-TCV recipients in the RCT attained higher anti-Vi IgG GMTs 42 days after immunization (SCN,97%;GMT, 1293 [95% confidence interval {CI}, 1153-1449]) than recipients of Typbar (SCN, 93%; GMT, 411 [95% CI,359-471]) (P <.001). Typbar-TCV was highly immunogenic in the OLT (SCN, 98%; GMT, 1937 [95% CI, 1785-2103]). Two years after vaccination, anti-Vi titers remained higher in Typbar-TCV subjects (GMT, 82 [95% CI, 73-92]); and exhibited higher avidity (geometric mean avidity index [GMAI], 60%) than in Typbar recipients (GMT, 46[95% CI, 40-53];GMAI 46%) in the RCT (P <.001). OLT Typbar-TCV recipients achieved GMT of 48 (95% CI, 42-55)and GMAI of 57%. Typbar-TCV induced multiple IgG subclasses and strong booster responses in all ages. No serious vaccine-attributable adverse events were obsd. Conclusions: Single-dose Typbar-TCV is well tolerated and induces robust and long-lasting serum anti-Vi IgGacross age groups.
      >> More from SciFinder ®
      https://chemport.cas.org/services/resolver?origin=ACS&resolution=options&coi=1%3ACAS%3A528%3ADC%252BC28XhvFakur3J&md5=e6f448c9f352c27c8cd18919d9d24709
    20. 20
      Zhao, J.; Hu, G.; Huang, Y.; Huang, Y. C.; Wei, X.; Shi, J. Y. Polysaccharide conjugate vaccine: A kind of vaccine with great development potential. Chin. Chem. Lett. 2021, 32 (4), 1331– 1340,  DOI: 10.1016/j.cclet.2020.10.013
      There is no corresponding record for this reference.
    21. 21
      Ahmad, T. A.; El-Sayed, L. H.; Haroun, M.; Hussein, A. A.; El Ashry, E. S. H. Development of immunization trials against Klebsiella pneumoniae. Vaccine 2012, 30 (14), 2411– 2420,  DOI: 10.1016/j.vaccine.2011.11.027
      There is no corresponding record for this reference.
    22. 22
      Hegerle, N.; Choi, M.; Sinclair, J.; Amin, M. N.; Ollivault-Shiflett, M.; Curtis, B.; Laufer, R. S.; Shridhar, S.; Brammer, J.; Toapanta, F. R. Development of a broad spectrum glycoconjugate vaccine to prevent wound and disseminated infections with Klebsiella pneumoniae and Pseudomonas aeruginosa. PLoS One 2018, 13 (9), e0203143  DOI: 10.1371/journal.pone.0203143
      There is no corresponding record for this reference.
    23. 23
      Miller, J. C.; Cross, A. S.; Tennant, S. M.; Baliban, S. M. Klebsiella pneumoniae Lipopolysaccharide as a Vaccine Target and the Role of Antibodies in Protection from Disease. Vaccines 2024, 12 (10), 1177,  DOI: 10.3390/vaccines12101177
      There is no corresponding record for this reference.
    24. 24
      Schumann, B.; Parameswarappa, S. G.; Lisboa, M. P.; Kottari, N.; Guidetti, F.; Pereira, C. L.; Seeberger, P. H. Nucleophile-Directed Stereocontrol Over Glycosylations Using Geminal-Difluorinated Nucleophiles. Angew. Chem., Int. Ed. 2016, 55 (46), 14431– 14434,  DOI: 10.1002/anie.201606774
      There is no corresponding record for this reference.
    25. 25
      Hahm, H. S.; Hurevich, M.; Seeberger, P. H. Automated assembly of oligosaccharides containing multiple cis-glycosidic linkages. Nat. Commun. 2016, 7, 12482,  DOI: 10.1038/ncomms12482
      25
      Automated assembly of oligosaccharides containing multiple cis-glycosidic linkages
      Hahm, Heung Sik; Hurevich, Mattan; Seeberger, Peter H.
      Nature Communications (2016), 7 (), 12482CODEN: NCAOBW; ISSN:2041-1723. (Nature Publishing Group)
      Automated glycan assembly (AGA) has advanced from a concept to a com. technol. that rapidly provides access to diverse oligosaccharide chains as long as 30-mers. To date, AGA was mainly employed to incorporate trans-glycosidic linkages, where C2 participating protecting groups ensure stereoselective couplings. Stereocontrol during the installation of cis-glycosidic linkages cannot rely on C2-participation and anomeric mixts. are typically formed. Here, we demonstrate that oligosaccharides contg. multiple cis-glycosidic linkages can be prepd. efficiently by AGA using monosaccharide building blocks equipped with remote participating protecting groups. The concept is illustrated by the automated syntheses of biol. relevant oligosaccharides bearing various cis-galactosidic and cis-glucosidic linkages. This work provides further proof that AGA facilitates the synthesis of complex oligosaccharides with multiple cis-linkages and other biol. important oligosaccharides.
      >> More from SciFinder ®
      https://chemport.cas.org/services/resolver?origin=ACS&resolution=options&coi=1%3ACAS%3A528%3ADC%252BC28XhsVKqs73E&md5=93b9e144bf44840b1ba4927068ed39b0
    26. 26
      Schumann, B.; Parameswarappa, S. G.; Lisboa, M. P.; Kottari, N.; Guidetti, F.; Pereira, C. L.; Seeberger, P. H. Nucleophile-Directed Stereocontrol Over Glycosylations Using Geminal-Difluorinated Nucleophiles. Angew. Chem., Int. Ed. 2016, 55 (46), 14431– 14434,  DOI: 10.1002/anie.201606774
      There is no corresponding record for this reference.
    27. 27
      Wang, S.; Meng, X.; Huang, W.; Yang, J.-S. Influence of Silyl Protections on the Anomeric Reactivity of Galactofuranosyl Thioglycosides and Application of the Silylated Thiogalactofuranosides to One-Pot Synthesis of Diverse β-d-Oligogalactofuranosides. J. Org. Chem. 2014, 79 (21), 10203– 10217,  DOI: 10.1021/jo5018684
      27
      Influence of Silyl Protections on the Anomeric Reactivity of Galactofuranosyl Thioglycosides and Application of the Silylated Thiogalactofuranosides to One-Pot Synthesis of Diverse β-D-Oligogalactofuranosides
      Wang, Shuai; Meng, Xue; Huang, Wei; Yang, Jin-Song
      Journal of Organic Chemistry (2014), 79 (21), 10203-10217CODEN: JOCEAH; ISSN:0022-3263. (American Chemical Society)
      We describe in this paper the tuning effect of silyl protecting groups on the donor reactivity of galactofuranosyl Ph thioglycosides. Silyl ethers on the galactofuranose ring are found to have an arming effect on the glycosylation reactivity, but the cyclic 3,5-acetal protecting group decreases the reactivity. The reactive Ph 2,6-di-O-Bz-3,5-di-O-TBS-1-thio-β-D-galactofuranoside 3 is proved to be a useful glycosyl building block. By taking advantage of this donor, we achieved the highly efficient one-pot soln.-phase assembly of a panel of β-D-galactofuranosyl tri- and tetrasaccharides possessing diverse glycosidic linkages.
      >> More from SciFinder ®
      https://chemport.cas.org/services/resolver?origin=ACS&resolution=options&coi=1%3ACAS%3A528%3ADC%252BC2cXhslChsbzM&md5=9f31eeeb1174b0f278238066c3809c09
    28. 28
      Pragani, R.; Seeberger, P. H. Total Synthesis of the Bacteroides fragilis Zwitterionic Polysaccharide A1 Repeating Unit. J. Am. Chem. Soc. 2011, 133 (1), 102– 107,  DOI: 10.1021/ja1087375
      28
      Total synthesis of the Bacteroides fragilis zwitterionic polysaccharide A1 repeating unit
      Pragani, Rajan; Seeberger, Peter H.
      Journal of the American Chemical Society (2011), 133 (1), 102-107CODEN: JACSAT; ISSN:0002-7863. (American Chemical Society)
      Nearly all bacteria capsular polysaccharides are T-cell-independent antigens that do not promote Ig class switching from IgM to IgG nor memory responses. In contrast, Zwitterionic polysaccharides activate T-cell-dependent immune responses by major histo-compatibility complex class II presentation, a mechanism previously believed to be reserved for peptidic antigens. The best studied zwitterionic polysaccharide, polysaccharide A1 (PS A1) is found on the capsule of the commensal bacteria Bacteroides fragilis. Its potent immunomodulatory properties have been linked to postoperative intra-abdominal abscess formation. Here, we report the synthesis of the PS A1 tetrasaccharide repeating unit as a tool to investigate the biol. role of this polysaccharide. A modular synthetic strategy originating from the reducing end of the PS A1 repeating unit was unsuccessful and illustrated the limitations of glycosylation reactions between highly armed glycosylating agents and poor nucleophiles. Thus, a [3+1] glycosylation relying on trisaccharide and pyruvalated galactose was used to complete the first total synthesis of the PS A1 tetrasaccharide repeating unit.
      >> More from SciFinder ®
      https://chemport.cas.org/services/resolver?origin=ACS&resolution=options&coi=1%3ACAS%3A528%3ADC%252BC3cXhsFClu7%252FF&md5=7879aff750f7a75884dff4e935911594
    29. 29
      Yang, Y.; Martin, C. E.; Seeberger, P. H. Total synthesis of the core tetrasaccharide of Neisseria meningitidislipopolysaccharide, a potential vaccine candidate for meningococcal diseases. Chem. Sci. 2012, 3 (3), 896– 899,  DOI: 10.1039/C1SC00804H
      There is no corresponding record for this reference.
    30. 30
      Geissner, A.; Anish, C.; Seeberger, P. H. Glycan arrays as tools for infectious disease research. Curr. Opin. Chem. Biol. 2014, 18, 38– 45,  DOI: 10.1016/j.cbpa.2013.11.013
      30
      Glycan arrays as tools for infectious disease research
      Geissner, Andreas; Anish, Chakkumkal; Seeberger, Peter H.
      Current Opinion in Chemical Biology (2014), 18 (), 38-45CODEN: COCBF4; ISSN:1367-5931. (Elsevier B.V.)
      A review. Infectious diseases cause millions of deaths worldwide each year and are a major burden for economies, esp. in underdeveloped countries. Glycans and their interactions with other biomols. are involved in all major steps of infection. Glycan arrays enable the rapid and sensitive detection of those interactions and are among the most powerful techniques to study the mol. biol. of infectious diseases. This review will focus on recent developments and discuss the applications of glycan arrays to the elucidation of host-pathogen and pathogen-pathogen interactions, the development of tools for infection diagnosis and the use of glycan arrays in modern vaccine design.
      >> More from SciFinder ®
      https://chemport.cas.org/services/resolver?origin=ACS&resolution=options&coi=1%3ACAS%3A528%3ADC%252BC2cXivF2mtro%253D&md5=ee840ac9f7389bbcc00818f3b107f34d
    31. 31
      Geissner, A.; Seeberger, P. H. Glycan Arrays: From Basic Biochemical Research to Bioanalytical and Biomedical Applications. Annu. Rev. Anal. Chem. 2016, 9 (1), 223– 247,  DOI: 10.1146/annurev-anchem-071015-041641
      There is no corresponding record for this reference.
    32. 32
      Mazmanian, S. K.; Kasper, D. L. The love-hate relationship between bacterial polysaccharides and the host immune system. Nat. Rev. Immunol. 2006, 6 (11), 849– 858,  DOI: 10.1038/nri1956
      There is no corresponding record for this reference.
    33. 33
      Astronomo, R. D.; Burton, D. R. Carbohydrate vaccines: developing sweet solutions to sticky situations?. Nat. Rev. Drug Discovery 2010, 9 (4), 308– 324,  DOI: 10.1038/nrd3012
      33
      Carbohydrate vaccines: developing sweet solutions to sticky situations?
      Astronomo, Rena D.; Burton, Dennis R.
      Nature Reviews Drug Discovery (2010), 9 (4), 308-324CODEN: NRDDAG; ISSN:1474-1776. (Nature Publishing Group)
      A review. Recent technol. advances in glycobiol. and glycochem. are paving the way for a new era in carbohydrate vaccine design. This is enabling greater efficiency in the identification, synthesis and evaluation of unique glycan epitopes found on a plethora of pathogens and malignant cells. Here, the authors review the progress being made in addressing challenges posed by targeting the surface carbohydrates of bacteria, protozoa, helminths, viruses, fungi and cancer cells for vaccine purposes.
      >> More from SciFinder ®
      https://chemport.cas.org/services/resolver?origin=ACS&resolution=options&coi=1%3ACAS%3A528%3ADC%252BC3cXktVGjtL4%253D&md5=9cb458281569cdd0df3a044161cd8eea
    34. 34
      Avci, F. Y.; Li, X.; Tsuji, M.; Kasper, D. L. A mechanism for glycoconjugate vaccine activation of the adaptive immune system and its implications for vaccine design. Nat. Med. 2011, 17 (12), 1602– 1609,  DOI: 10.1038/nm.2535
      34
      A mechanism for glycoconjugate vaccine activation of the adaptive immune system and its implications for vaccine design
      Avci, Fikri Y.; Li, Xiangming; Tsuji, Moriya; Kasper, Dennis L.
      Nature Medicine (New York, NY, United States) (2011), 17 (12), 1602-1609CODEN: NAMEFI; ISSN:1078-8956. (Nature Publishing Group)
      Glycoconjugate vaccines have provided enormous health benefits globally, but they have been less successful in some populations at high risk for developing disease. To identify new approaches to enhancing glycoconjugate effectiveness, we investigated mol. and cellular mechanisms governing the immune response to a prototypical glycoconjugate vaccine. We found that in antigen-presenting cells a carbohydrate epitope is generated upon endolysosomal processing of group B streptococcal type III polysaccharide coupled to a carrier protein. In conjunction with a carrier protein-derived peptide, this carbohydrate epitope binds major histocompatibility class II (MHCII) and stimulates carbohydrate-specific CD4+ T cell clones to produce interleukins 2 and 4-cytokines essential for providing T cell help to antibody-producing B cells. An archetypical glycoconjugate vaccine that we constructed to maximize the presentation of carbohydrate-specific T cell epitopes is 50-100 times more potent and substantially more protective in a neonatal mouse model of group B Streptococcus infection than a vaccine constructed by methods currently used by the vaccine industry. Our discovery of how glycoconjugates are processed resulting in presentation of carbohydrate epitopes that stimulate CD4+ T cells has key implications for glycoconjugate vaccine design that could result in greatly enhanced vaccine efficacy.
      >> More from SciFinder ®
      https://chemport.cas.org/services/resolver?origin=ACS&resolution=options&coi=1%3ACAS%3A528%3ADC%252BC3MXhsV2gt7%252FL&md5=c02d36037865b38be13179ca1eb84fce
    35. 35
      Shinefield, H. R. Overview of the development and current use of CRM(197) conjugate vaccines for pediatric use. Vaccine 2010, 28 (27), 4335– 4339,  DOI: 10.1016/j.vaccine.2010.04.072
      There is no corresponding record for this reference.
    36. 36
      Esteves, P. J.; Abrantes, J.; Baldauf, H. M.; BenMohamed, L.; Chen, Y.; Christensen, N.; Gonzalez-Gallego, J.; Giacani, L.; Hu, J.; Kaplan, G. The wide utility of rabbits as models of human diseases. Exp. Mol. Med. 2018, 50 (5), 1– 10,  DOI: 10.1038/s12276-018-0094-1
      There is no corresponding record for this reference.
    37. 37
      Kaplonek, P.; Khan, N.; Reppe, K.; Schumann, B.; Emmadi, M.; Lisboa, M. P.; Xu, F. F.; Calow, A. D. J.; Parameswarappa, S. G.; Witzenrath, M. Improving vaccines against Streptococcus pneumoniae using synthetic glycans. Proc. Natl. Acad. Sci. U.S.A. 2018, 115 (52), 13353– 13358,  DOI: 10.1073/pnas.1811862115
      37
      Improving vaccines against Streptococcus pneumoniae using synthetic glycans
      Kaplonek, Paulina; Khan, Naeem; Reppe, Katrin; Schumann, Benjamin; Emmadi, Madhu; Lisboa, Marilda P.; Xu, Fei-Fei; Calow, Adam D. J.; Parameswarappa, Sharavathi G.; Witzenrath, Martin; Pereira, Claney L.; Seeberger, Peter H.
      Proceedings of the National Academy of Sciences of the United States of America (2018), 115 (52), 13353-13358CODEN: PNASA6; ISSN:0027-8424. (National Academy of Sciences)
      Streptococcus pneumoniae remains a deadly disease in small children and the elderly even though conjugate and polysaccharide vaccines based on isolated capsular polysaccharides (CPS) are successful. The most common serotypes that cause infection are used in vaccines around the world, but differences in geog. and demog. serotype distribution compromises protection by leading vaccines. The medicinal chem. approach to glycoconjugate vaccine development has helped to improve the stability and immunogenicity of synthetic vaccine candidates for several serotypes leading to the induction of higher levels of specific protective antibodies. Here, we show that marketed CPS-based glycoconjugate vaccines can be improved by adding synthetic glycoconjugates representing serotypes that are not covered by existing vaccines. Combination (coformulation) of synthetic glycoconjugates with the licensed vaccines Prevnar13 (13-valent) and Synflorix (10-valent) yields improved 15- and 13-valent conjugate vaccines, resp., in rabbits. A pentavalent semisynthetic glycoconjugate vaccine contg. five serotype antigens (sPCV5) elicits antibodies with strong in vitro opsonophagocytic activity. This study illustrates that synthetic oligosaccharides can be used in coformulation with both isolated polysaccharide glycoconjugates to expand protection from existing vaccines and each other to produce precisely defined multi-valent conjugated vaccines.
      >> More from SciFinder ®
      https://chemport.cas.org/services/resolver?origin=ACS&resolution=options&coi=1%3ACAS%3A528%3ADC%252BC1cXisF2rsrfE&md5=d84a363b169710f09461695053692e19
    38. 38
      Sanapala, S. R.; Seco, B. M. S.; Baek, J. Y.; Awan, S. I.; Pereira, C. L.; Seeberger, P. H. Chimeric oligosaccharide conjugate induces opsonic antibodies against Streptococcus pneumoniae serotypes 19A and 19F. Chem. Sci. 2020, 11 (28), 7401– 7407,  DOI: 10.1039/D0SC02230F
      38
      Chimeric oligosaccharide conjugate induces opsonic antibodies against Streptococcus pneumoniae serotypes 19A and 19F
      Sanapala, Someswara Rao; Seco, Bruna M. S.; Baek, Ju Yuel; Awan, Shahid I.; Pereira, Claney L.; Seeberger, Peter H.
      Chemical Science (2020), 11 (28), 7401-7407CODEN: CSHCCN; ISSN:2041-6520. (Royal Society of Chemistry)
      Streptococcus pneumoniae 19A (ST19A) and 19F (ST19F) are among the prevalent serotypes causing pneumococcal disease worldwide even after introduction of a 13-valent pneumococcal conjugate vaccine (PCV13). Synthetic glycoconjugate vaccines have defined chem. structures rather than isolated polysaccharide mixts. utilized in marketed vaccines. Ideally, a minimal no. of synthetic antigens would cover as many bacterial serotypes to lower cost of goods and minimize the response to carrier proteins. To demonstrate that a chimeric oligosaccharide antigen can induce a protective immune response against multiple serotypes, we synthesized a chimeric antigen (ST19AF) that is comprised of a repeating unit of ST19A and ST19F capsular polysaccharide each. Synthetic glycan epitopes representing only ST19A, and ST19F were prepd. for comparison. Semisynthetic glycoconjugates contg. chimeric antigen ST19AF induced high antibody titers able to recognize native CPS from ST19A and ST19F in rabbits. The antibodies were able to kill both strains of pneumococci. Chimeric antigens are an attractive means to induce an immune response against multiple bacterial serotypes.
      >> More from SciFinder ®
      https://chemport.cas.org/services/resolver?origin=ACS&resolution=options&coi=1%3ACAS%3A528%3ADC%252BB3cXht1OgtLvN&md5=4d1545e3b031c95777f819fb520e479e
    39. 39
      Rappuoli, R. Glycoconjugate vaccines: Principles and mechanisms. Sci. Transl. Med. 2018, 10 (456), eaat4615  DOI: 10.1126/scitranslmed.aat4615
      There is no corresponding record for this reference.
    40. 40
      Clarke, B. R.; Ovchinnikova, O. G.; Kelly, S. D.; Williamson, M. L.; Butler, J. E.; Liu, B.; Wang, L.; Gou, X.; Follador, R.; Lowary, T. L. Molecular basis for the structural diversity in serogroup O2-antigen polysaccharides in Klebsiella pneumoniae. J. Biol. Chem. 2018, 293 (13), 4666– 4679,  DOI: 10.1074/jbc.RA117.000646
      There is no corresponding record for this reference.
    41. 41
      Bulati, M.; Busa, R.; Carcione, C.; Iannolo, G.; Di Mento, G.; Cuscino, N.; Di Gesu, R.; Piccionello, A. P.; Buscemi, S.; Carreca, A. P. Klebsiella pneumoniae Lipopolysaccharides Serotype O2afg Induce Poor Inflammatory Immune Responses Ex Vivo. Microorganisms 2021, 9 (6), 1317,  DOI: 10.3390/microorganisms9061317
      There is no corresponding record for this reference.
    42. 42
      Peng, Z.; Wu, J.; Wang, K.; Li, X.; Sun, P.; Zhang, L.; Huang, J.; Liu, Y.; Hua, X.; Yu, Y. Production of a Promising Biosynthetic Self-Assembled Nanoconjugate Vaccine against Klebsiella Pneumoniae Serotype O2 in a General Escherichia Coli Host. Adv. Sci. 2021, 8 (14), e2100549  DOI: 10.1002/advs.202100549
      There is no corresponding record for this reference.
    43. 43
      Cohen, T. S.; Pelletier, M.; Cheng, L.; Pennini, M. E.; Bonnell, J.; Cvitkovic, R.; Chang, C. S.; Xiao, X.; Cameroni, E.; Corti, D. Anti-LPS antibodies protect against Klebsiella pneumoniae by empowering neutrophil-mediated clearance without neutralizing TLR4. JCI Insight 2017, 2 (9), e92774  DOI: 10.1172/jci.insight.92774
      There is no corresponding record for this reference.
    44. 44
      Avci, F. Y.; Li, X.; Tsuji, M.; Kasper, D. L. Carbohydrates and T cells: a sweet twosome. Semin. Immunol. 2013, 25 (2), 146– 151,  DOI: 10.1016/j.smim.2013.05.005
      44
      Carbohydrates and T cells: A sweet twosome
      Avci, Fikri Y.; Li, Xiangming; Tsuji, Moriya; Kasper, Dennis L.
      Seminars in Immunology (2013), 25 (2), 146-151CODEN: SEIME2; ISSN:1044-5323. (Elsevier Ltd.)
      A review. Carbohydrates as T cell-activating antigens have been generating significant interest. For many years, carbohydrates were thought of as T-independent antigens, however, more recent research had demonstrated that mono- or oligosaccharides glycosidically linked to peptides can be recognized by T cells. T cell recognition of these glycopeptides depends on the structure of both peptide and glycan portions of the antigen. Subsequently, it was discovered that natural killer T cells recognized glycolipids when presented by the antigen presenting mol. CD1d. A transformative insight into glycan-recognition by T cells occurred when zwitterionic polysaccharides were discovered to bind to and be presented by MHCII to CD4+ T cells. Based on this latter observation, the role that carbohydrate epitopes generated from glycoconjugate vaccines had in activating helper T cells was explored and it was found that these epitopes are presented to specific carbohydrate recognizing T cells through a unique mechanism. Here we review the key interactions between carbohydrate antigens and the adaptive immune system at the mol., cellular and systems levels exploring the significant biol. implications in health and disease.
      >> More from SciFinder ®
      https://chemport.cas.org/services/resolver?origin=ACS&resolution=options&coi=1%3ACAS%3A528%3ADC%252BC3sXptFGmtrs%253D&md5=f30ff826b12bbc6660cbb16cfaea834f
    45. 45
      Dwyer, M.; Gadjeva, M. Opsonophagocytic assay. Methods Mol. Biol. 2014, 1100, 373– 379,  DOI: 10.1007/978-1-62703-724-2_32
      There is no corresponding record for this reference.
    46. 46
      Burton, R. L.; Kim, H. W.; Lee, S.; Kim, H.; Seok, J. H.; Lee, S. H.; Balloch, A.; Licciardi, P.; Marimla, R.; Bae, S. Creation, characterization, and assignment of opsonic values for a new pneumococcal OPA calibration serum panel (Ewha QC sera panel A) for 13 serotypes. Medicine 2018, 97 (17), e0567  DOI: 10.1097/MD.0000000000010567
      There is no corresponding record for this reference.
    47. 47
      Jodar, L.; Butler, J.; Carlone, G.; Dagan, R.; Goldblatt, D.; Kayhty, H.; Klugman, K.; Plikaytis, B.; Siber, G.; Kohberger, R. Serological criteria for evaluation and licensure of new pneumococcal conjugate vaccine formulations for use in infants. Vaccine 2003, 21 (23), 3265– 3272,  DOI: 10.1016/S0264-410X(03)00230-5
      There is no corresponding record for this reference.
    48. 48
      Munford, R. S. Murine responses to endotoxin: another dirty little secret?. J. Infect. Dis. 2010, 201 (2), 175– 177,  DOI: 10.1086/649558
      48
      Murine responses to endotoxin: another dirty little secret?
      Munford Robert S
      The Journal of infectious diseases (2010), 201 (2), 175-7 ISSN:.
      There is no expanded citation for this reference.
      >> More from SciFinder ®
      https://chemport.cas.org/services/resolver?origin=ACS&resolution=options&coi=1%3ACAS%3A280%3ADC%252BD1MfksFWhuw%253D%253D&md5=5c38e3e4548faa548091ddca192ad8b1
    49. 49
      Reinhart, K.; Daniels, R.; Kissoon, N.; Machado, F. R.; Schachter, R. D.; Finfer, S. Recognizing Sepsis as a Global Health Priority - A WHO Resolution. N. Engl. J. Med. 2017, 377 (5), 414– 417,  DOI: 10.1056/NEJMp1707170
      There is no corresponding record for this reference.
    50. 50
      Haegens, A.; Vernooy, J. H.; Heeringa, P.; Mossman, B. T.; Wouters, E. F. Myeloperoxidase modulates lung epithelial responses to pro-inflammatory agents. Eur. Respir. J. 2008, 31 (2), 252– 260,  DOI: 10.1183/09031936.00029307
      There is no corresponding record for this reference.
    51. 51
      Matute-Bello, G.; Downey, G.; Moore, B. B.; Groshong, S. D.; Matthay, M. A.; Slutsky, A. S.; Kuebler, W. M. An Official American Thoracic Society Workshop Report: Features and Measurements of Experimental Acute Lung Injury in Animals. Am. J. Respir. Cell Mol. Biol. 2011, 44 (5), 725– 738,  DOI: 10.1165/rcmb.2009-0210ST
      51
      An official american thoracic society workshop report: features and measurements of experimental acute lung injury in animals
      Matute-Bello, Gustavo; Downey, Gregory; Moore, Bethany B.; Groshong, Steve D.; Matthay, Michael A.; Slutsky, Arthur S.; Kuebler, Wolfgang M.
      American Journal of Respiratory Cell and Molecular Biology (2011), 44 (5), 725-738CODEN: AJRBEL; ISSN:1044-1549. (American Thoracic Society)
      Acute lung injury (ALI) is well defined in humans, but there is no agreement as to the main features of acute lung injury in animal models. A Committee was organized to det. the main features that characterize ALI in animal models and to identify the most relevant methods to assess these features. We used a Delphi approach in which a series of questionnaires were distributed to a panel of experts in exptl. lung injury. The Committee concluded that the main features of exptl. ALI include histol. evidence of tissue injury, alteration of the alveolar capillary barrier, presence of an inflammatory response, and evidence of physiol. dysfunction; they recommended that, to det. if ALI has occurred, at least three of these four main features of ALI should be present. The Committee also identified key "very relevant" and "somewhat relevant" measurements for each of the main features of ALI and recommended the use of least one "very relevant" measurement and preferably one or two addnl. sep. measurements to det. if a main feature of ALI is present. Finally, the Committee emphasized that not all of the measurements listed can or should be performed in every study, and that measurements not included in the list are by no means "irrelevant.". Our list of features and measurements of ALI is intended as a guide for investigators, and ultimately investigators should choose the particular measurements that best suit the exptl. questions being addressed as well as take into consideration any unique aspects of the exptl. design.
      >> More from SciFinder ®
      https://chemport.cas.org/services/resolver?origin=ACS&resolution=options&coi=1%3ACAS%3A528%3ADC%252BC3MXot1Kjtr8%253D&md5=74e2c3187741c2fd5f3c0d8330bfef0e
    52. 52
      Klopfleisch, R. Multiparametric and semiquantitative scoring systems for the evaluation of mouse model histopathology--a systematic review. BMC Vet. Res. 2013, 9, 123,  DOI: 10.1186/1746-6148-9-123
      There is no corresponding record for this reference.
    53. 53
      West, J. B. Perivascular edema, a factor in pulmonary vascular resistance. Am. Heart J. 1965, 70 (4), 570– 572,  DOI: 10.1016/0002-8703(65)90370-4
      There is no corresponding record for this reference.
    54. 54
      Fein, A. M.; Calalang-Colucci, M. G. Acute lung injury and acute respiratory distress syndrome in sepsis and septic shock. Crit. Care Clin. 2000, 16 (2), 289– 317,  DOI: 10.1016/S0749-0704(05)70111-1
      There is no corresponding record for this reference.
    55. 55
      Kumar, V.; Chhibber, S. Acute lung inflammation in Klebsiella pneumoniae B5055-induced pneumonia and sepsis in BALB/c mice: a comparative study. Inflammation 2011, 34 (5), 452– 462,  DOI: 10.1007/s10753-010-9253-9
      There is no corresponding record for this reference.
    56. 56
      Dickerhof, N.; Huang, J.; Min, E.; Michaelsson, E.; Lindstedt, E. L.; Pearson, J. F.; Kettle, A. J.; Day, B. J. Myeloperoxidase inhibition decreases morbidity and oxidative stress in mice with cystic fibrosis-like lung inflammation. Free Radic. Biol. Med. 2020, 152, 91– 99,  DOI: 10.1016/j.freeradbiomed.2020.03.001
      There is no corresponding record for this reference.
    57. 57
      Sugamata, R.; Dobashi, H.; Nagao, T.; Yamamoto, K.; Nakajima, N.; Sato, Y.; Aratani, Y.; Oshima, M.; Sata, T.; Kobayashi, K. Contribution of neutrophil-derived myeloperoxidase in the early phase of fulminant acute respiratory distress syndrome induced by influenza virus infection. Microbiol. Immunol. 2012, 56 (3), 171– 182,  DOI: 10.1111/j.1348-0421.2011.00424.x
      There is no corresponding record for this reference.
    58. 58
      Saikam, V.; Dara, S.; Yadav, M.; Singh, P. P.; Vishwakarma, R. A. Dimethyltin Dichloride Catalyzed Regioselective Alkylation of cis-1,2-Diols at Room Temperature. J. Org. Chem. 2015, 80 (24), 11916– 11925,  DOI: 10.1021/acs.joc.5b01898
      There is no corresponding record for this reference.
    59. 59
      Deng, L. M.; Liu, X.; Liang, X. Y.; Yang, J. S. Regioselective glycosylation method using partially protected arabino- and galactofuranosyl thioglycosides as key glycosylating substrates and its application to one-pot synthesis of oligofuranoses. J. Org. Chem. 2012, 77 (7), 3025– 3037,  DOI: 10.1021/jo300084g
      59
      Regioselective Glycosylation Method Using Partially Protected Arabino- and Galactofuranosyl Thioglycosides as Key Glycosylating Substrates and Its Application to One-Pot Synthesis of Oligofuranoses
      Deng, Li-Min; Liu, Xia; Liang, Xing-Yong; Yang, Jin-Song
      Journal of Organic Chemistry (2012), 77 (7), 3025-3037CODEN: JOCEAH; ISSN:0022-3263. (American Chemical Society)
      We describe in this paper the development of a novel regioselective furanosylation methodol. using partially protected furanosyl thioglycosides as central glycosylating building blocks and its application in the efficient one-pot synthesis of a series of linear and branched-type arabino- and galactofuranoside fragments structurally related to the cell wall polysaccharides of Mycobacterium tuberculosis, Streptococcus pneumoniae sero-stype 35A, and sugar beet.
      >> More from SciFinder ®
      https://chemport.cas.org/services/resolver?origin=ACS&resolution=options&coi=1%3ACAS%3A528%3ADC%252BC38XivVOht7g%253D&md5=58eef1614a5179098045298ca80977ff
    60. 60
      Wu, X.; Ling, C. C.; Bundle, D. R. A new homobifunctional p-nitro phenyl ester coupling reagent for the preparation of neoglycoproteins. Org. Lett. 2004, 6 (24), 4407– 4410,  DOI: 10.1021/ol048614m
      60
      A New Homobifunctional p-Nitro Phenyl Ester Coupling Reagent for the Preparation of Neoglycoproteins
      Wu, Xiangyang; Ling, Chang-Chun; Bundle, David R.
      Organic Letters (2004), 6 (24), 4407-4410CODEN: ORLEF7; ISSN:1523-7060. (American Chemical Society)
      A new linker system has been designed and applied to neoglycoprotein synthesis. Reaction of oligosaccharide ω-aminoalkyl glycosides with homobifunctional adipic acid p-nitrophenyl diesters in dry DMF gave the corresponding amide half ester in good yields and of sufficient stability to permit chromatog. purifn. Subsequent conjugation with bovine serum albumin under very mild conditions afforded the corresponding neoglycoproteins with good efficiency. The method is well suited for the coupling of very small amts. (mg) of oligosaccharide and protein.
      >> More from SciFinder ®
      https://chemport.cas.org/services/resolver?origin=ACS&resolution=options&coi=1%3ACAS%3A528%3ADC%252BD2cXovFSlsLY%253D&md5=60840ed71db1cda743aa29010fb227cb
    61. 61
      Moor, K.; Fadlallah, J.; Toska, A.; Sterlin, D.; Balmer, M. L.; Macpherson, A. J.; Gorochov, G.; Larsen, M.; Slack, E. Analysis of bacterial-surface-specific antibodies in body fluids using bacterial flow cytometry. Nat. Protoc. 2016, 11 (8), 1531– 1553,  DOI: 10.1038/nprot.2016.091
      61
      Analysis of bacterial-surface-specific antibodies in body fluids using bacterial flow cytometry
      Moor Kathrin; Toska Albulena; Slack Emma; Fadlallah Jehane; Sterlin Delphine; Gorochov Guy; Larsen Martin; Balmer Maria L; Macpherson Andrew J; Balmer Maria L; Gorochov Guy; Larsen Martin
      Nature protocols (2016), 11 (8), 1531-53 ISSN:.
      Antibacterial antibody responses that target surfaces of live bacteria or secreted toxins are likely to be relevant in controlling bacterial pathogenesis. The ability to specifically quantify bacterial-surface-binding antibodies is therefore highly attractive as a quantitative correlate of immune protection. Here, binding of antibodies from various body fluids to pure-cultured live bacteria is made visible with fluorophore-conjugated secondary antibodies and measured by flow cytometry. We indicate the necessary controls for excluding nonspecific binding and also demonstrate a cross-adsorption technique for determining the extent of cross-reactivity. This technique has numerous advantages over standard ELISA and western blotting techniques because of its independence from scaffold binding, exclusion of cross-reactive elements from lysed bacteria and ability to visualize bacterial subpopulations. In addition, less than 10(5) bacteria and less than 10 μg of antibody are required per sample. The technique requires 3-4 h of hands-on experimentation and analysis. Moreover, it can be combined with automation and mutliplexing for high-throughput applications.
      >> More from SciFinder ®
      https://chemport.cas.org/services/resolver?origin=ACS&resolution=options&coi=1%3ACAS%3A280%3ADC%252BC2s3ls1CltQ%253D%253D&md5=123a8e137f962c18aa5fb75bec0255b6
    62. 62
      Burton, R. L.; Nahm, M. H. Development and validation of a fourfold multiplexed opsonization assay (MOPA4) for pneumococcal antibodies. Clin. Vaccine Immunol. 2006, 13 (9), 1004– 1009,  DOI: 10.1128/CVI.00112-06
      62
      Development and validation of a fourfold multiplexed opsonization assay (MOPA4) for pneumococcal antibodies
      Burton, Robert L.; Nahm, Moon H.
      Clinical and Vaccine Immunology (2006), 13 (9), 1004-1009CODEN: CVILA6; ISSN:1556-6811. (American Society for Microbiology)
      Opsonophagocytic killing assays (OPAs) are essential for developing and improving pneumococcal vaccines. There is a need for a high-throughput, reliable, standardized, and fully characterized OPA for pneumococcal antibodies. To meet the need, the authors have developed and characterized a fourfold multiplexed OPA (MOPA4) against 13 serotypes (1, 3, 4, 5, 6A, 6B, 7F, 9V, 14, 18C, 19A, 19F, and 23F) of pneumococci. Thirteen target bacteria were made resistant to only one of the following antibiotics: optochin, streptomycin, spectinomycin, and trimethoprim. Following optimization of assay conditions, accuracy of MOPA4 was detd. by testing 30 sera from old adults in the MOPA4 and the single-serotype assays. The opsonization titers obtained with both assays agreed well (r2 > 0.95). Although 22 (out of 390; ∼6%) results differed more than twofold, the differences were not reproducible. The assay was specific: preabsorbing test sera with homologous polysaccharide (PS) completely abrogated opsonic activity, but a pool of unrelated PS (5 μg/mL of each) had no effect. Intra- and interassay coeffs. of variation were 10 and 22%, resp. MOPA4 results were unaffected by having different target pneumococcal serotypes in each assay group. Also, HL60 cell-to-bacteria ratios could be varied twofold without affecting the results. The authors conclude that MOPA4 is sensitive, accurate, specific, precise, and robust enough for large-scale clin. studies. Furthermore, MOPA4 should allow evaluation of multivalent pneumococcal vaccines with the limited vol. of serum typically available from young children.
      >> More from SciFinder ®
      https://chemport.cas.org/services/resolver?origin=ACS&resolution=options&coi=1%3ACAS%3A528%3ADC%252BD28XhtVWgt73L&md5=2de17f60d8defbb969318a81b730c460
    63. 63
      Szijarto, V.; Guachalla, L. M.; Hartl, K.; Varga, C.; Banerjee, P.; Stojkovic, K.; Kaszowska, M.; Nagy, E.; Lukasiewicz, J.; Nagy, G. Both clades of the epidemic KPC-producing Klebsiella pneumoniae clone ST258 share a modified galactan O-antigen type. Int. J. Med. Microbiol. 2016, 306 (2), 89– 98,  DOI: 10.1016/j.ijmm.2015.12.002
      There is no corresponding record for this reference.

  • Supporting Information

    Supporting Information

    The Supporting Information is available free of charge at https://pubs.acs.org/doi/10.1021/jacs.4c13972.

    • Experimental methods and characterization, including synthesis of the compounds, glycan microarray studies, conjugation, with in vitro and in vivo assays to evaluate the vaccine lead (PDF)

    • 1H-, 13C-, and HSQC-NMR spectra for new compounds (PDF)


    Terms & Conditions

    Most electronic Supporting Information files are available without a subscription to ACS Web Editions. Such files may be downloaded by article for research use (if there is a public use license linked to the relevant article, that license may permit other uses). Permission may be obtained from ACS for other uses through requests via the RightsLink permission system: http://pubs.acs.org/page/copyright/permissions.html.