A comprehensive analysis of antigen-specific antibody responses against human cytomegalovirus in patients with systemic sclerosis

Abstract Anti-human cytomegalovirus (HCMV) antibodies are considered triggers of systemic sclerosis (SSc), but such a hypothesis has been assessed in limited sub-dominant epitopes. Our aim was to systematically assess the potential association of HCMV antibodies targeting most immunodominant and subdominant viral antigens, as this would reveal immunopathogenic associations. Our study included 110 SSc patients, 60 multiple sclerosis (MS) patients, and 51 healthy controls (HC). Anti-HCMV abs were tested by immunoblotting. IgG anti-HCMV was broader in SSc and MS compared to HC. Anti- UL57 and UL55 were more frequent in SSc versus MS forms. Reactivity to multiple viral antigens was more frequent in SSc than MS forms. Anti-viral antibodies levels were higher in specific autoantibody-positive SSc patients compared to seronegative cases. In conclusion, more prevalent and/or stronger antigen-specific HCMV responses are noted in SSc compared to controls, implying a role of these viral responses in SSc development.