CD4 and Chronic colitis: We have been able to demonstrate that administration of neutralizing TL1A antibodies not only prevents but also treats established chronic colitis, likely by directly blocking IFN-γ production by TH1 cells and IL-17 and IL-6 production from TH17 cells, and also by blocking the enhancing effect of TL1A/IL-12 and TL1A/IL-23 on these CD4+ T cell subsets [8].