Studies have shown that depletion of NK cells can strongly exacerbate disease in mouse models of chronic inflammation, including myelin oligodendrocyte glycoprotein (MOG)-induced experimental autoimmune encephalomyelitis (EAE) [5], a model of multiple sclerosis (MS), as well as Staphylococcus aureus- and collagen-induced arthritis (CIA) [6], [7]. This evidence concerns the gene MOG and multiple sclerosis.