In particular, a strong reduction in disease severity or a complete lack of disease has been reported when OX40 or OX40L is absent or neutralized in animal models of multiple sclerosis (MS) [21], allergic asthma [22], colitis [23], diabetes [24], arthritis [25], atherosclerosis [26], graft versus host disease [27], and allograft rejection [28]. This evidence concerns the gene TNFRSF4 and myeloid sarcoma.