TGF-beta1: immunosuppressant and viability factor for T lymphocytes.
Transforming growth factor-beta (TGF-beta) is a multifunctional cytokine with multiple roles in the immune system. To date, it has been difficult to develop a comprehensive picture of the effect of TGF-beta on T lymphocytes, because TGF-beta not only acts directly on T lymphocytes, but also acts indirectly by regulating the function of antigen-presenting cells. In early studies, it was mostly the inhibitory function of TGF-beta that was demonstrated; recently, however TGF-beta was recognized as an antiapoptotic survival factor for T lymphocytes. The outcome of the TGF-beta effect on T lymphocytes was shown to strongly depend on their stage of differentiation and on the cytokine milieu. TGF-beta cannot be classified as a classical Th1 or Th2 cytokine. However, recently the existence of the TGF-beta-producing Th3 subset was described which might play an important regulatory role during an immune response. A better understanding of the molecular mechanism of how TGF-beta inhibits or stimulates T lymphocytes will help to predict the complex functions of this cytokine.
Cerwenka
A
A
Trudeau Institute, Saranac Lake, NY 12983, USA.
Swain
S L
SL
D000818:Animals; D006801:Humans; D007165:Immunosuppression Therapy; D051379:Mice; D013601:T-Lymphocytes / Q000187:drug effects* / Q000502:physiology*; D016212:Transforming Growth Factor beta / Q000378:metabolism / Q000494:pharmacology*
D016212:Transforming Growth Factor beta