We have demonstrated the effectiveness of using a panel of MHC class II (DRB1*15:01 or DRB1*04:01) tetramers loaded with myelin epitopes from myelin basic protein (MBP), proteolipid protein (PLP), and myelin oligodendrocyte glycoprotein (MOG) to study autoreactive T cells in MS (4, 5, 47, 48). Here, MBP is linked to myeloid sarcoma.