Interleukin 4 mediates autocrine growth of helper T cells after antigenic stimulation.
The role of interleukin 4 (IL-4) (previously called B-cell stimulatory factor 1) in the response of T helper (TH) cells to antigen presented by antigen-specific B cells or splenic adherent cells was investigated. Antigenic stimulation of either a keyhole-limpet-hemocyanin-specific TH-cell line or two keyhole-limpet-hemocyanin-specific T-cell clones resulted in the secretion of IL-4 but not interleukin 2 (IL-2). The secretion of IL-4 was first detected in the culture supernatant 6-8 hr after antigenic stimulation. Induction of IL-4 secretion was antigen specific and major histocompatibility complex restricted. Antigenic stimulation also resulted in increased responsiveness of the TH cells to exogenously added or endogenously produced IL-4. The antigen-induced proliferation of the TH cells could be inhibited by an anti-IL-4 antibody but not by an anti-IL-2-receptor antibody. These results suggest that IL-4 mediates the proliferation of some TH cells by an antigen-induced autocrine mechanism. Taken together with past results, these data indicate that, during T-cell-B-cell interactions involving some soluble protein antigens, IL-4 and not IL-2 is the critical lymphokine for activating resting B cells and inducing proliferation of the TH cells.
D000818:Animals; D000911:Antibodies, Monoclonal / Q000276:immunology; D000941:Antigens / Q000276:immunology; D002460:Cell Line; D006133:Growth Substances / Q000235:genetics / Q000276:immunology*; D006433:Hemocyanins / Q000276:immunology; D007376:Interleukin-2 / Q000235:genetics / Q000276:immunology*; D015847:Interleukin-4; D008213:Lymphocyte Activation; D008222:Lymphokines / Q000235:genetics / Q000276:immunology*; D051379:Mice; D012333:RNA, Messenger / Q000235:genetics; D011971:Receptors, Immunologic / Q000276:immunology; D015375:Receptors, Interleukin-2; D006377:T-Lymphocytes, Helper-Inducer / Q000166:cytology / Q000276:immunology*
D000911:Antibodies, Monoclonal; D000941:Antigens; D006133:Growth Substances; D007376:Interleukin-2; D008222:Lymphokines; D012333:RNA, Messenger; D011971:Receptors, Immunologic; D015375:Receptors, Interleukin-2; D015847:Interleukin-4; D006433:Hemocyanins