While some studies suggest a regulatory role of CD8 T lymphocytes on CD4 T cell activity (Zozulya and Wiendl, 2008) and dendritic cell activation (Kashi et al., 2014) during experimental autoimmune encephalomyelitis (EAE), other demonstrate that CD8 T cells aggravate CD4 T cell mediated EAE (Mars et al., 2007). The gene discussed is CD8A; the disease is experimental autoimmune encephalomyelitis.