On the other hand, amelioration of disease symptoms and improved health were observed after delivery of IL-21 neutralizing antibodies or IL-21R blockade in mice in multiple autoimmune and inflammatory disease models, including SLE (139), arthritis (140), graft-vs.-host disease (GVHD) (141, 142), and Crohn's Disease (143). Here, IL21R is linked to graft versus host disease.