Figure 2.
Model of IL23 mediated resistance to apoptosis of mucosal CD4+ T cells in anti-TNF refractory Crohn’s disease patients. In anti-TNF refractory patients, TNFR2 bearing gut CD4+ T cells express the IL23R. Heightened production of IL23 from CD14+ macrophages leads to binding to the IL23R on CD4+TNFR2+ T cells and induction of STAT3 activation. This activation leads to the expansion of CD4+IL23R+TNFR2+ T cells that are resistant to apoptosis induction by anti-TNF antibodies, resulting in the perpetuation of mucosal inflammation.