RPA1 and multiple sclerosis: RPA1 plays a key role in DNA replication, recombination and repair in epithelial cells.[14] RPA1 is also implicated in somatic hypermutation and class‐switched recombination in B cells.[24, 25] Interestingly, recent study identified RPA1 mutation in CD8+ T cells from patients with multiple sclerosis.[26] However, little is known about the role of RPA1 in T cell‐mediated immune response.