title: T-cell replacing factor activity of recombinant-derived interleukin-2 requires gamma-interferon.
abstract: In this study we show that recombinant-derived human interleukin-2 (rIL-2) has potent T-cell replacing activity in antigen-driven murine antibody responses of T-depleted spleen cells. This T-cell replacing factor (TRF) effect of rIL-2 is antigen specific. By the use of a variety of antibodies to gamma-interferon (IFN-gamma), including antibody from an interspecies hybridoma, we demonstrate that this TRF activity depends upon the production of IFN-gamma in the responding cell cultures, i.e., antibody to IFN-gamma blocks TRF activity. In addition, we show that the cell-to-cell allogeneic helper effect of T cells for antibody responses is similarly inhibited by antibodies to IFN-gamma. The inhibition of response produced by the antibodies is reversed by the addition of excess rIFN-gamma to the cultures. The results demonstrate that IFN-gamma is a necessary intermediate mediator for TRF activity mediated by IL-2 and also by T-cell-mediated help for B cells. Thus, even recombinant-derived lymphokines have complex secondary levels of action on responding cells. Antibodies to individual lymphokines are clearly a powerful resource to analyze the role of soluble factors in cellular responses.
mesh_terms: D000818:Animals; D000906:Antibodies / Q000276:immunology; D000941:Antigens / Q000276:immunology; D001402:B-Lymphocytes / Q000276:immunology; D007371:Interferon-gamma / Q000276:immunology*; D007376:Interleukin-2 / Q000276:immunology*; D015848:Interleukin-5; D008222:Lymphokines / Q000276:immunology*; D051379:Mice; D008815:Mice, Inbred Strains; D013154:Spleen / Q000276:immunology; D013601:T-Lymphocytes / Q000276:immunology
chemical_list: D000906:Antibodies; D000941:Antigens; D007376:Interleukin-2; D015848:Interleukin-5; D008222:Lymphokines; D007371:Interferon-gamma