CD4 and colitis: To determine how SCFA-GPR43 interaction regulates the function of Th1 cells and inhibits Th1 cell induction of colitis, we generated Th1 cells by culture of CD4+ T-cells from WT CBir1 and Gpr43−/− CBir1 Tg mice under Th1-polarizing conditions with IL-12 for 5-days for two cycles.