Document resource
Background T lymphocytes, particularly Th1 and Th17 cells,are pivotal in the pathogenesis of autoimmune disorders such as multiple sclerosis(MS) and psoriasis. We propose that the co-occurrence of psoriasis and MS (PsoMS) represents a distinct clinical variant of MS,characterised by the involvement of specific T lymphocyte subsets. This study aims to delineate the T cell subsets that underlie the shared immunopathogenesis of MS and psoriasis.Method Mass cytometry was performed to identify and quantify T cells subsets (T con,T reg,Th1,Th2,Th17 and Th17.1) in MS patients(n=25), MS with psoriasis (PsoMS,n=12) and healthy control (HC,n=10). Flow data were analyzed using Flow Cytometry Analysis Software.GraphPad Prism was selected for statistical analysis.One-way ANOVA was conducted for three independent groups comparison.Results A significant depletion of Th1 (CXCR3 +CCR4-CCR6-) and Th17.1 (CXCR3+CCR4-CCR6+) subsets was observed in MS [p=0.0027 for Th1 and p=0.0485 for Th17.1] and PsoMS groups [p=0.0130 for Th1 and p=0.0272 for Th17.1] compared to healthy control(HC). This reduction was consistent across all MS subgroups, regardless of coexisting psoriasis or type of therapy.Notably, further phenotyping demonstrated a psoMS-specific deficit in CCR5 expression across all T helper subsets. Interestingly, the CCR5 deficiency was exclusively revealed in patients treated with non-B cell therapies, suggesting a therapeutic specific effect in psoriatic-MS sub-type.Conclusion We report the link between Th1/Th17.1 and MS subtypes using comprehensive immunophenotyping. The study, utilizing high-dimensional cytometry to identify cellular phenotypes, underscores the critical role of Th17.1 lymphocytes in MS pathogenesis and highlights them as a potential therapeutic target.