title: Adhesion and degranulation-promoting adapter protein (ADAP) positively regulates T cell sensitivity to antigen and T cell survival.
abstract: The hemopoietic specific adapter protein ADAP (adhesion and degranulation-promoting adapter protein) positively regulates TCR-dependent, integrin-mediated adhesion and participates in signaling pathways downstream of the TCR that result in T cell activation. The specific role of ADAP in regulating Ag-dependent T cell interactions with APCs and T cell activation following Ag stimulation is not known. We used ADAP-/- DO11.10 T cells to demonstrate that ADAP promotes T cell conjugation to Ag-laden APCs. Complementary in vitro and in vivo approaches reveal that ADAP controls optimal T cell proliferation, cytokine production, and expression of the prosurvival protein Bcl-xL in response to limiting Ag doses. Furthermore, ADAP is critical for clonal expansion in vivo independent of Ag concentration under conditions of low clonal abundance. These results suggest that ADAP regulates T cell activation by promoting Ag-dependent T cell-APC interactions, resulting in enhanced T cell sensitivity to Ag, and by participating in prosurvival signaling pathways initiated by Ag stimulation.
authors.affiliation: Department of Laboratory Medicine and Pathology, Center for Immunology, Cancer Center, University of Minnesota Medical School, Minneapolis, MN 55455, USA.
authors.forename: Kristen L
authors.initials: KL
authors.lastname: Mueller
authors.forename: Molly S
authors.initials: MS
authors.lastname: Thomas
authors.forename: Brandon J
authors.initials: BJ
authors.lastname: Burbach
authors.forename: Erik J
authors.initials: EJ
authors.lastname: Peterson
authors.forename: Yoji
authors.initials: Y
authors.lastname: Shimizu
mesh_terms: D048868:Adaptor Proteins, Signal Transducing / Q000172:deficiency / Q000235:genetics / Q000502:physiology*; D000818:Animals; D017951:Antigen Presentation / Q000276:immunology; D000938:Antigen-Presenting Cells / Q000276:immunology / Q000378:metabolism; D015703:Antigens, CD / Q000096:biosynthesis; D000945:Antigens, Differentiation, T-Lymphocyte / Q000096:biosynthesis; D015496:CD4-Positive T-Lymphocytes / Q000166:cytology* / Q000276:immunology* / Q000378:metabolism; D002448:Cell Adhesion / Q000276:immunology; D015550:Cell Degranulation / Q000276:immunology*; D049109:Cell Proliferation; D002470:Cell Survival / Q000276:immunology; D002478:Cells, Cultured; D002999:Clone Cells; D004306:Dose-Response Relationship, Immunologic; D018984:Epitopes, T-Lymphocyte / Q000276:immunology*; D016023:Integrins / Q000502:physiology; D007376:Interleukin-2 / Q000096:biosynthesis; D053645:Interleukin-2 Receptor alpha Subunit / Q000096:biosynthesis; D037181:Lectins, C-Type; D008213:Lymphocyte Activation / Q000276:immunology; D016169:Lymphocyte Function-Associated Antigen-1 / Q000502:physiology; D051379:Mice; D008807:Mice, Inbred BALB C; D018345:Mice, Knockout; D008822:Mice, Transgenic; D015854:Up-Regulation / Q000276:immunology*; D000099192:CD69 Antigens