CD4 and multiple sclerosis: Since B cells with EBV type I latency are only controlled by EBNA-1-specific CD4 T cells (123–125), these results suggest a reduction in the immune response to EBV infection in HLA-DR15+ individuals, while proinflammatory effects, as well as an increased CD4 T-cell cross-reactivity may increase the risk of developing autoimmune diseases, such as multiple sclerosis (121, 122).