Among patients with systemic sclerosis (SSc), but not systemic lupus erythematosus (SLE), there are differences between those with and without anti-Ro52 antibodies in the prevalence and titers against human cytomegalovirus (HCMV) antigens, according to study results published in Rheumatology International.
Anti-Ro52 antibodies are very common in patients with Sjögren syndrome, SLE, and SSc. Viral antigens, including HCMV, have been suggested to be potential triggers of SSc and SSc-related antibodies. The objective of the current study was to explore the association between anti-Ro52 antibodies with antibody responses against specific HCMV antigens in patients with SSc and SLE.
Researchers assessed serum samples from 58 patients with SSc (54 women; mean age, 57.2 years) and 32 patients with SLE (31 women; mean age, 52.1 years). Anti-Ro52 antibodies were identified in 29 patients with SSc and 23 patients with SLE. An additional control group included 26 patients with Sjögren syndrome, of whom 18 were anti-Ro52 antibody-positive.
All participants received testing for the anti-HCMV antibody by serology and antigen-specific antibodies against 4 HCMV antigens, including pp130/UL57, pp65/UL83, pp55/UL55, pp52/UL44, p38 and pp28/UL99. Study findings suggest that 2 major HCMV antigens were more frequently recognized in anti-Ro52 antibody-positive patients than anti-Ro52 antibody-negative patients with SSc: pp52/UL44 (44.8% vs 3.4%, respectively; P <.001) and p38 (31.0% vs 6.9%, respectively; P =.041). However, among patients with SLE or Sjögren syndrome, there was no difference between anti-Ro52 antibody-positive and anti-Ro52 antibody-negative patients, suggesting an SSc-specific antiviral/Ro52 antibody association.
In addition, titers of anti-pp65/UL83, anti-pp52/UL44, and anti-p38 abs were higher in anti-Ro52 antibody-positive patients than anti-Ro52 antibody-negative patients with SSc (P <.01). Similarly, titers of anti-pp65/UL83 antibodies were higher in anti-Ro52 antibody-positive patients than anti-Ro52 antibody-negative patients with SLE or Sjögren syndrome.
“Whether this finding is epiphenomenal or has pathogenic significance for the understanding of the induction of Ro52 autoantibodies, the third most common autoantibody reactivity on SSc, remains to be clarified,” wrote the researchers.
Disclosure: Several study authors declared affiliations with the pharmaceutical industry. Please see the original reference for a full list of authors’ disclosures.
Gkoutzourelas A, Liaskos C, Simopoulou T, et al. A study of antigen-specific anti-cytomegalovirus antibody reactivity in patients with systemic sclerosis and concomitant anti-Ro52 antibodies [published online July 17, 2020]. Rheumatol Int. doi:10.1007/s00296-020-04643-z