Furthermore, increased frequencies of Tc17 cells were detected in peripheral blood (PB) of MS patients as compared to healthy controls14 and Tc17 cells were present in active areas of acute and in chronic MS lesions alongside with IL-17-producing CD4+ (Th17) T cells15, implicating a contribution of both subpopulations to MS pathogenesis. The gene discussed is CD4; the disease is myeloid sarcoma.