title: Allogeneic non-T spleen cells restore the responsiveness of normal T cell clones stimulated with antigen and chemically modified antigen-presenting cells.
abstract: Stimulation of IL-2-producing T cell clones with chemically modified APC and Ag induces a state of proliferative unresponsiveness, i.e., subsequent stimulation with normal APC and Ag fails to elicit IL-2 production. One possible effect of chemical modification on the APC is the destruction of its ability to provide costimulatory signals. To test this, various potential costimulators were added to T cells at the time of exposure to Ag and chemically modified APC. None of the cytokines tested, including IL-1, had a positive effect; however, addition of allogeneic spleen cells allowed a T cell proliferative response and prevented the induction of subsequent unresponsiveness. Fractionation of the spleen cells showed that low density B cells and macrophages were the best source of costimulatory activity. Allogeneic resting B cells provided some costimulatory activity and resting T cells, none at all. Attempts to mimic costimulatory signals with the phorbol ester PMA were only partially successful. PMA prevented the induction of T cell unresponsiveness but failed to allow T cell proliferation in response to Ag plus chemically modified APC. Our results suggest that IL-2 production by normal T cell clones is dependent not only on T cell receptor occupancy, but also on short range costimulatory signals that are provided to different degrees by various non-T accessory cells.
authors.affiliation: Laboratory of Cellular and Molecular Immunology, National Institute of Allergy and Infectious Diseases, Bethesda, MD 20892.
authors.forename: M K
authors.initials: MK
authors.lastname: Jenkins
authors.forename: J D
authors.initials: JD
authors.lastname: Ashwell
authors.forename: R H
authors.initials: RH
authors.lastname: Schwartz
mesh_terms: D000818:Animals; D000938:Antigen-Presenting Cells / Q000187:drug effects / Q000276:immunology*; D002450:Cell Communication; D002999:Clone Cells / Q000276:immunology; D003574:Cytochrome c Group / Q000276:immunology*; D005022:Ethyldimethylaminopropyl Carbodiimide / Q000494:pharmacology; D007375:Interleukin-1 / Q000494:pharmacology; D007377:Interleukin-3 / Q000494:pharmacology; D007519:Isoantigens / Q000276:immunology; D008213:Lymphocyte Activation / Q000187:drug effects; D008211:Lymphocyte Cooperation; D051379:Mice; D008810:Mice, Inbred C57BL; D013154:Spleen / Q000166:cytology*; D013601:T-Lymphocytes / Q000276:immunology*; D013755:Tetradecanoylphorbol Acetate / Q000494:pharmacology
chemical_list: D003574:Cytochrome c Group; D007375:Interleukin-1; D007377:Interleukin-3; D007519:Isoantigens; D013755:Tetradecanoylphorbol Acetate; D005022:Ethyldimethylaminopropyl Carbodiimide