CD4 and myeloid sarcoma: Dysregulation of immune effector–suppressor cell interactions results in an autoimmune response against CNS antigens.69 The hypothesis about the autoimmune origin of MS derives from studies on experimental autoimmune encephalomyelitis (EAE), an experimental model of MS in which disease can be induced by immunization with CNS-derived proteins and is largely driven by CNS-specific CD4+ T cells.70–76 A critical event in MS immunopathogenesis is disruption of the BBB, which normally restricts immune cell entry into the CNS.