title: p38 mitogen-activated protein kinase mediates signal integration of TCR/CD28 costimulation in primary murine T cells.
abstract: Optimal T cell activation requires two signals, one generated by TCR and another by the CD28 costimulatory receptor. In this study, we investigated the regulation of costimulation-induced mitogen-activated protein kinase (MAPK) activation in primary mouse T cells. In contrast to that reported for human Jurkat T cells, we found that p38 MAPK, but not Jun NH2-terminal kinase (JNK), is weakly activated upon stimulation with either anti-CD3 or anti-CD28 in murine thymocytes and splenic T cells. However, p38 MAPK is activated strongly and synergistically by either CD3/CD28 coligation or PMA/Ca2+ ionophore stimulation, which mimics TCR-CD3/CD28-mediated signaling. Activation of p38 MAPK correlates closely with the stimulation of T cell proliferation. In contrast, PMA-induced JNK activation is inhibited by Ca2+ ionophore. T cell proliferation and production of IL-2, IL-4, and IFN-gamma induced by both CD3 and CD3/CD28 ligation and the nuclear expression of the c-Jun and ATF-2 proteins are each blocked by the p38 MAPK inhibitor SB203580. Our findings demonstrate that p38 MAPK 1) plays an important role in signal integration during costimulation of primary mouse T cells, 2) may be involved in the induction of c-Jun activation and augmentation of AP-1 transcriptional activity, and 3) regulates whether T cells enter a state of functional unresponsiveness.
authors: Autoimmunity/Diabetes Group, John P. Robarts Research Institute, London, Ontario, Canada.
authors: J
authors: J
authors: Zhang
authors: K V
authors: KV
authors: Salojin
authors: J X
authors: JX
authors: Gao
authors: M J
authors: MJ
authors: Cameron
authors: I
authors: I
authors: Bergerot
authors: T L
authors: TL
authors: Delovitch
mesh_terms: D051698:Activating Transcription Factor 2; D000818:Animals; D018106:CD28 Antigens / Q000276:immunology*; D017252:CD3 Complex / Q000276:immunology / Q000378:metabolism; D002118:Calcium / Q000502:physiology; D017871:Calcium-Calmodulin-Dependent Protein Kinases / Q000378:metabolism*; D002467:Cell Nucleus / Q000187:drug effects / Q000201:enzymology / Q000378:metabolism; D002478:Cells, Cultured; D017362:Cyclic AMP Response Element-Binding Protein / Q000037:antagonists & inhibitors / Q000096:biosynthesis; D016207:Cytokines / Q000037:antagonists & inhibitors / Q000378:metabolism; D004357:Drug Synergism; D004789:Enzyme Activation; D006801:Humans; D007093:Imidazoles / Q000494:pharmacology; D048031:JNK Mitogen-Activated Protein Kinases; D019169:Jurkat Cells; D008213:Lymphocyte Activation / Q000187:drug effects; D051379:Mice; D008807:Mice, Inbred BALB C; D008810:Mice, Inbred C57BL; D020928:Mitogen-Activated Protein Kinases; D016755:Proto-Oncogene Proteins c-jun / Q000037:antagonists & inhibitors / Q000096:biosynthesis; D011725:Pyridines / Q000494:pharmacology; D011948:Receptors, Antigen, T-Cell / Q000276:immunology*; D015398:Signal Transduction / Q000187:drug effects / Q000276:immunology*; D013601:T-Lymphocytes / Q000187:drug effects / Q000201:enzymology* / Q000276:immunology* / Q000378:metabolism; D014157:Transcription Factors / Q000037:antagonists & inhibitors / Q000096:biosynthesis; D048051:p38 Mitogen-Activated Protein Kinases
chemical_list: C497105:ATF2 protein, human; D051698:Activating Transcription Factor 2; C497106:Atf2 protein, mouse; D018106:CD28 Antigens; D017252:CD3 Complex; D017362:Cyclic AMP Response Element-Binding Protein; D016207:Cytokines; D007093:Imidazoles; D016755:Proto-Oncogene Proteins c-jun; D011725:Pyridines; D011948:Receptors, Antigen, T-Cell; D014157:Transcription Factors; D017871:Calcium-Calmodulin-Dependent Protein Kinases; D048031:JNK Mitogen-Activated Protein Kinases; D020928:Mitogen-Activated Protein Kinases; D048051:p38 Mitogen-Activated Protein Kinases; C093642:SB 203580; D002118:Calcium