CD4 and colitis: As compared to CD11chiCD45RB− conventional DCs, the expanded cells exert better protection against colitis induction by CD4+ CD25− T cells, even though both subpopulations show similar ability to induce Tregs in vivo. The better control of proinflammatory cytokine responses in vivo by the expanded cells is associated with more apoptosis in the Payer’s patches and in colonic tissue-infiltrating cells.