IFNG and systemic sclerosis: The effects of IFN-γ on fibroblasts in vitro are conflicting; exogenous IFN-γ was suggested to abrogate TGF-β1-induced proliferation, migration, and differentiation to myofibroblasts [176]; but T-cell secretion of IFN-γ, found to be prominent in SSc, aggravated fibrosis by promoting fibroblast proliferation and collagen synthesis [177].