Differential distribution of antiviral serology across multiple sclerosis phenotypes and its implications for disease pathogenesis.

Multiple sclerosis (MS) is a heterogeneous inflammatory disease of the central nervous system in which environmental factors, particularly viral infections, are thought to contribute to disease susceptibility and progression. However, whether antiviral immune responses differ across clinical phenotypes remains incompletely understood. In this study, we analyzed the distribution of antiviral serology in patients with primary progressive, relapsing–remitting, and secondary progressive MS, comparing them with healthy controls. Serum IgG responses against several neurotropic and non-neurotropic viruses were assessed and evaluated according to disease phenotype, clinical characteristics, and disability measures. We observed distinct serological profiles among MS subtypes, with differential patterns of antiviral antibody prevalence and titers. Notably, specific antiviral responses were associated with progressive forms of the disease and with markers of greater clinical severity. These findings suggest that antiviral immunity is not uniform across MS phenotypes and may reflect divergent pathogenic mechanisms underlying disease progression. Our results support a potential role for virus–host interactions in shaping the clinical course of MS and highlight antiviral serology as a complementary tool to improve disease stratification. Understanding these immune signatures may contribute to refining pathogenic models and identifying novel targets for personalized therapeutic strategies.