CD8A and dermatomyositis: This phenomenon is somewhat consistent with the early reports that CD8 T cells are decreased more significantly than CD4 T cells in patients with severe MDA5+DM.[13,14] The reason for a more severe decrease of CD8 T cells is not clear, but given that CD8 T cells are highly activated in activated MDA5+DM patients,[10] it is plausible that activated CD8 T cells could be recruited to affected tissues.