Vitamin D/dexamethasone-induced DCreg secretion of TGFβ suppresses both IFNγ production and proliferation of CD4+ T cells from rheumatoid arthritis patients (73), just as TGFβ produced by steady state CD8α+ DC or all-trans retinoic acid-induced DCreg (DC-RA) contributes to suppression of allergic donor Teff cell responses in mouse models (51, 74). Here, CD4 is linked to rheumatoid arthritis.