CD8A and myeloid sarcoma: These data show that pwMS treated with alemtuzumab, cladribine, and natalizumab have robust humoral and CD4 and CD8 T cell responses after 2 vaccine doses, in agreement with other studies (3, 14, 20, 22, 25), although it should be noted that alemtuzumab-treated individuals had last received treatment an average of 3 years previously, which may have contributed to higher Ab responses comparable to individuals without MS; although T cell populations are suppressed for up to 5 years after treatment, B cell populations recover within months (38).