In vitro human TGF-β treatment converts CD4+CD25- T cells into induced T regulatory like cells

In mammals, induced T regulatory cells (iTregs) are produced by treating CD4(+)CD25(-) cells in vitro with TGF-beta in the presence of anti-CD3 and IL-2 Chicken CD4(+)CD25(-) cells were treated in vitro with TGF-beta, anti-CD3, anti-CD28 and IL-2 and analyzed for suppressive properties, IL-10 and IL-2 mRNA amounts. TGF-beta treatment decreased (P < 0.01) CD4(+)CD25(-) cell proliferation by 45% at 5d of cell culture with no increase in dead cell population CD4(+)CD25(-) cells treated with 5 ng TGF-beta for 5 d had 130-fold (P < 0.01) more IL-10 and 104-fold (P < 0.01) less IL-2 mRNA content than the 0 ng TGF-beta treated groups. CD4(+)CD25(-) cells treated with 5 ng TGF-beta for 5 d suppressed (P < 0.01) naive cell proliferation compared to the 0 ng TGF-beta treated groups The results suggest the presence of iTreg-like cells in avian species Published by Elsevier B V