TGFB1 and colitis: Importantly, however, in a model of colitis where it was found that TGF-β1-deficient Treg cells were capable of suppressing inflammation to the same extent as control Treg cells, use of a TGF-β blocking antibody completely abrogated Treg-cell-mediated suppression, showing that TGF-β from non-Treg cell sources is capable of promoting suppression of inflammatory T cells (Fahlén et al., 2005).