title: Interleukin 7 is a T-cell growth factor.
abstract: Interleukin 7 (IL-7) is a 25-kDa cytokine which was purified and its corresponding cDNA was cloned based upon its ability to stimulate the proliferation of pre-B cells. It has been shown that IL-7 can also function as a costimulator with Con A for the proliferation of T lymphocytes by inducing the production of interleukin 2 (IL-2). We demonstrate here that IL-7 in combination with phorbol 12-myristate 13-acetate can directly drive the proliferation of purified T cells and that this response is not inhibited by cyclosporine A or by antibodies to IL-2 and IL-4. Stimulation of T cells with phorbol myristate acetate and IL-2, IL-4, or IL-7 prepared T cells to respond to any of the three lymphokines. Although T cells activated in vitro by anti-CD3 or allogeneic cells failed to proliferate when challenged with IL-7, T cells primed in vivo to the same stimuli demonstrated a significant proliferative response when restimulated in vitro with IL-7. IL-7 can, therefore, function both as a growth factor for T cells in an IL-2-independent manner and as a competence factor for the induction of lymphokine responsiveness. The ability to induce IL-7 responsiveness via stimulation of the T-cell receptor complex in vivo, but not in vitro, raises the possibility that IL-7 may play a role in T-cell growth and differentiation in vivo.
authors: Laboratory of Immunology, National Institute of Allergy and Infectious Diseases, Bethesda, MD 20892.
authors: G D
authors: GD
authors: Chazen
authors: G M
authors: GM
authors: Pereira
authors: G
authors: G
authors: LeGros
authors: S
authors: S
authors: Gillis
authors: E M
authors: EM
authors: Shevach
mesh_terms: D000818:Animals; D000911:Antibodies, Monoclonal; D002478:Cells, Cultured; D003208:Concanavalin A / Q000494:pharmacology; D004261:DNA Replication / Q000187:drug effects; D005260:Female; D015851:Interleukin-7; D007378:Interleukins / Q000276:immunology / Q000494:pharmacology*; D008198:Lymph Nodes / Q000187:drug effects / Q000276:immunology; D008213:Lymphocyte Activation / Q000187:drug effects*; D051379:Mice; D008807:Mice, Inbred BALB C; D008810:Mice, Inbred C57BL; D011994:Recombinant Proteins / Q000494:pharmacology; D013601:T-Lymphocytes / Q000166:cytology / Q000187:drug effects / Q000276:immunology*; D013755:Tetradecanoylphorbol Acetate / Q000494:pharmacology
chemical_list: D000911:Antibodies, Monoclonal; D015851:Interleukin-7; D007378:Interleukins; D011994:Recombinant Proteins; D003208:Concanavalin A; D013755:Tetradecanoylphorbol Acetate