In experimental autoimmune encephalomyelitis (EAE), an animal model of MS, autoimmune Th1 cells activated by injected myelin antigens release cytokines including interferon-γ (IFN-γ) and interleukin-2 (IL-2) which attract the macrophages into the central nervous system (CNS) and induce the inflammation [2–4]. The gene discussed is IL2; the disease is myeloid sarcoma.