Data from both MS patients and experimental autoimmune encephalomyelitis (EAE), an animal model of MS, indicate that NK cells are associated with disease activity and therapeutic response in MS (155, 156), although their precise role is controversial On one hand, blockade of the interaction between the NK cell inhibitory receptor NKG2A and its ligand Qa-1 with an antibody that is equivalent to human leukocyte antigen (HLA)-E alleviated CNS inflammation in EAE by promoting the cytotoxic action of NK cells on T cells and microglia (157, 158). This evidence concerns the gene HLA-E and myeloid sarcoma.