“…The cytokine-producing Treg in these studies were anergic in vitro without the addition of IL-2, and were suppressive in Tconv co-cultures ( Refs 54,68,70,71,72 A beneficial role in the protection against infection has been proposed for cytokineproducing Treg (Refs 54, 73, 76), with some evidence for specific expansion and cytokine production against certain pathogenic antigens (Refs 54, 76). Moreover, there is evidence that such Treg may play a beneficial role during transplantation (Refs 76, 78): if IFN-γ production is blocked or specifically knocked out in Treg in a transplant model, mice suffer from graftversus-host disease.…”