CD4 and colitis: For colitis to develop in the T cell transfer model, T effector cells must expand and differentiate into Th1/Th17 proinflammatory lineages and also traffic efficiently to the intestines, where they will initiate inflammation and mucosal destruction.27,30 Interestingly, whilst harvesting the tissues from recipient mice having undergone T cell transfer, we observed marked splenomegaly and lymphadenopathy in Il36r−/− CD4+ T cell recipient mice.