Interleukin 2 in cell-mediated immune responses.
The lymphokine Interleukin 2(IL2) restores T cell responses in a number of in vitro systems where immunogenicity has been compromised. UV irradiation of the stimulating allogeneic cells in a mixed leukocyte culture eliminates the production of cytotoxic T lymphocytes and greatly reduces the DNA synthesis response. IL2 restores both parameters. UV-irradiated stimulators are also unable to induce the normal production of IL2 which is observed in a mixed leukocyte culture. The cytotoxic activity of allogeneically stimulated thymocytes is almost completely lost within 24 hours after removal of IL2 at 5 days, indicating that the lymphokine is continuously required to maintain CTL. Thymocytes in 4-day cultures do not adsorb IL2 unless they are simultaneously activated with a mitogen. Finally, IL2 does not adequately restore a secondary response to the purified protein derivative of tuberculin (PPD) in adherent-cell-depleted cultures, indicating that macrophages, in addition to being required for IL2 production, have other functions. These probably include the presentation of soluble antigens to responding cells.
D000818:Animals; D003602:Cytotoxicity, Immunologic; D007111:Immunity, Cellular / Q000528:radiation effects; D007376:Interleukin-2 / Q000494:pharmacology*; D008213:Lymphocyte Activation; D008222:Lymphokines / Q000494:pharmacology*; D008264:Macrophages / Q000276:immunology; D051379:Mice; D008815:Mice, Inbred Strains; D013601:T-Lymphocytes / Q000276:immunology; D014466:Ultraviolet Rays
D007376:Interleukin-2; D008222:Lymphokines