title: Blocked signal transduction to the ERK and JNK protein kinases in anergic CD4+ T cells.
abstract: T cells activated by antigen receptor stimulation in the absence of accessory cell-derived costimulatory signals lose the capacity to synthesize the growth factor interleukin-2 (IL-2), a state called clonal anergy. An analysis of CD3- and CD28-induced signal transduction revealed reduced ERK and JNK enzyme activities in murine anergic T cells. The amounts of ERK and JNK proteins were unchanged, and the kinases could be fully activated in the presence of phorbol 12-myristate 13-acetate. Dephosphorylation of the calcineurin substrate NFATp (preexisting nuclear factor of activated T cells) also remained inducible. These results suggest that a specific block in the activation of ERK and JNK contributes to defective IL-2 production in clonal anergy.
authors.affiliation: Department of Medicine, University of Minnesota Medical School, Minneapolis 55455, USA.
authors.forename: W
authors.initials: W
authors.lastname: Li
authors.forename: C D
authors.initials: CD
authors.lastname: Whaley
authors.forename: A
authors.initials: A
authors.lastname: Mondino
authors.forename: D L
authors.initials: DL
authors.lastname: Mueller
mesh_terms: D000818:Animals; D018106:CD28 Antigens / Q000276:immunology; D017252:CD3 Complex / Q000276:immunology; D017871:Calcium-Calmodulin-Dependent Protein Kinases / Q000378:metabolism*; D017635:Clonal Anergy; D002999:Clone Cells; D016572:Cyclosporine / Q000494:pharmacology; D004268:DNA-Binding Proteins / Q000378:metabolism; D004742:Enhancer Elements, Genetic; D004789:Enzyme Activation; D007376:Interleukin-2 / Q000096:biosynthesis; D015759:Ionomycin / Q000494:pharmacology; D048031:JNK Mitogen-Activated Protein Kinases; D008213:Lymphocyte Activation; D051379:Mice; D019950:Mitogen-Activated Protein Kinase 1; D048052:Mitogen-Activated Protein Kinase 3; D020928:Mitogen-Activated Protein Kinases; D050778:NFATC Transcription Factors; D009687:Nuclear Proteins; D011505:Protein-Tyrosine Kinases / Q000378:metabolism; D015398:Signal Transduction; D006377:T-Lymphocytes, Helper-Inducer / Q000201:enzymology / Q000276:immunology*; D013755:Tetradecanoylphorbol Acetate / Q000494:pharmacology; D018808:Transcription Factor AP-1 / Q000378:metabolism; D014157:Transcription Factors / Q000378:metabolism
chemical_list: D018106:CD28 Antigens; D017252:CD3 Complex; D004268:DNA-Binding Proteins; D007376:Interleukin-2; D050778:NFATC Transcription Factors; D009687:Nuclear Proteins; D018808:Transcription Factor AP-1; D014157:Transcription Factors; D015759:Ionomycin; D016572:Cyclosporine; D011505:Protein-Tyrosine Kinases; D017871:Calcium-Calmodulin-Dependent Protein Kinases; D048031:JNK Mitogen-Activated Protein Kinases; D019950:Mitogen-Activated Protein Kinase 1; D048052:Mitogen-Activated Protein Kinase 3; D020928:Mitogen-Activated Protein Kinases; D013755:Tetradecanoylphorbol Acetate