title: Macrophage-derived nitric oxide inhibits the proliferation of activated T helper cells and is induced during antigenic stimulation of resting T cells.
abstract: To examine how macrophage-derived nitric oxide (NO) affects T helper (Th) cell activity, T cell clones representing Th1 and Th2 subsets were activated before exposure to stimulated peritoneal macrophages or microglia. Both Th subsets were similarly sensitive to inhibition by NO, indicating that macrophage-derived NO regulates the proliferation of activated Th1 and Th2 cells equally well. Since IFN-gamma production remained intact in NO-treated Th1 cells, we studied whether NO was produced during antigen-specific activation of Th1 cells by unstimulated macrophages. Indeed, T cell proliferation only occurred when a NO synthase inhibitor was included, while IFN-gamma was essential for the induction of NO. These studies demonstrate that macrophages produce NO following antigen presentation to Th1 cells and that macrophage-derived NO inhibits Th1 and Th2 cell proliferation without inhibiting cytokine production.
authors.affiliation: Department of Neurology, University of Southern California School of Medicine, Los Angeles, California 90033, USA.
authors.forename: R C
authors.initials: RC
authors.lastname: van der Veen
authors.forename: T A
authors.initials: TA
authors.lastname: Dietlin
authors.forename: J
authors.initials: J
authors.lastname: Dixon Gray
authors.forename: W
authors.initials: W
authors.lastname: Gilmore
mesh_terms: D000818:Animals; D000941:Antigens / Q000276:immunology*; D017209:Apoptosis / Q000187:drug effects; D002455:Cell Division / Q000187:drug effects; D002478:Cells, Cultured; D018920:Coculture Techniques; D005260:Female; D007371:Interferon-gamma / Q000096:biosynthesis; D015848:Interleukin-5 / Q000096:biosynthesis; D008213:Lymphocyte Activation / Q000187:drug effects / Q000276:immunology*; D008262:Macrophage Activation; D017737:Macrophages, Peritoneal / Q000187:drug effects / Q000201:enzymology / Q000276:immunology / Q000378:metabolism*; D051379:Mice; D008815:Mice, Inbred Strains; D017628:Microglia / Q000187:drug effects / Q000201:enzymology / Q000276:immunology / Q000378:metabolism; D009569:Nitric Oxide / Q000378:metabolism*; D019001:Nitric Oxide Synthase / Q000037:antagonists & inhibitors / Q000378:metabolism; D010455:Peptides / Q000276:immunology; D018417:Th1 Cells / Q000166:cytology / Q000187:drug effects / Q000276:immunology* / Q000378:metabolism; D018418:Th2 Cells / Q000166:cytology / Q000187:drug effects / Q000276:immunology* / Q000378:metabolism; D019323:omega-N-Methylarginine / Q000494:pharmacology
chemical_list: D000941:Antigens; D015848:Interleukin-5; D010455:Peptides; D019323:omega-N-Methylarginine; D009569:Nitric Oxide; D007371:Interferon-gamma; D019001:Nitric Oxide Synthase