Differential effect of transforming growth factor β on the synthesis of Th1‐ and Th2‐like lymphokines by human T lymphocytes

Abstract

(TGF)‐β is a pluripotent cytokine exerting differential effects on distinct components of the immune response. The present report, based on lymphokine determination in culture supernatants and Northern blot analysis of lympokine mRNA, demonstrates that TGF‐β₂ markedly inhibits interleukin (IL)‐4 and IL‐5 synthesis by polyclonally activatted human T cells in the absence of any significant effect on (IFN)‐γ, lymphotoxin or IL‐2, suggesting a modulatory effect of TGF‐β₂ on the ineterferon T_h1/T_h2) balance of immune respnses. The inhibitory effect of TGF‐β on IFN‐γ production by unfractionated peripheral blood mononuclear cells is likely to reflect the blunting of natural killer cell activation by TGF‐β.