Cytomegalovirus (CMV) is a suspect because of its frequent association with autoimmunity and the ability to interact with the immune system in a variety of ways. Once individuals are infected, they carry CMV in a dormant form for life (like all other human herpesviruses), so there is the potential for reactivation.

CMV. Schematic of cytomegalovirus, which could play a role in inducing autoimmune responses in a subset of patients with systemic lupus erythematosus.

In a case-control immunological study of healthy people who were either CMV-positive or CMV-negative, an international research team from Canada, The Netherlands, and the United States recently found a significant correlation between CMV infection and a particular set of autoimmune responses (respondent to the U1 small nuclear ribonucleoprotein complexes, U1 snRNP) (Arthritis Res. 2001, 3, 253–258). Moreover, the groups characterized the CMV antibody response in patients with autoimmune diseases. The study revealed a notable association with the CMV-positive serostatus for SLE patients but not those with another autoimmune condition, mixed connective-tissue disease.

These results suggest some evidence that CMV plays a role in inducing U1 snRNP autoimmune responses in SLE patients. The subset of SLE patients with such autoantibodies selectively show disease features such as Raynaud’s phenomenon, arthritis, and late-onset renal disease. In addition to providing new information toward understanding the workings of lupus, these findings have implications for the prospective development of recombinant anti-CMV vaccines, suggesting that persons receiving such trial inoculations should be tested for autoantibody formation.