title: Adhesion- and degranulation-promoting adapter protein is required for efficient thymocyte development and selection.
abstract: Adhesion- and degranulation-promoting adapter protein (ADAP) is required in TCR-induced activation and proliferation of peripheral T cells. Loss of ADAP also impairs TCR-initiated inside-out activation of the integrin LFA-1 (CD11a/CD18, alphaLbeta2). In this study, we demonstrate that ADAP-deficient CD4/CD8 double-positive (DP) cells have a diminished ability to proliferate, and that these DP thymocytes up-regulate CD69 poorly in vivo. Moreover, in both MHC class I- and class II-restricted TCR transgenic models, loss of ADAP interferes with both positive and negative selection. ADAP deficiency also impairs the ability of transgene-bearing DP thymocytes to form conjugates with Ag-loaded presenting cells. These findings suggest that ADAP is critical for thymocyte development and selection.
authors.affiliation: Abramson Family Cancer Research Institute and Department of Laboratory Medicine and Pathology, School of Medicine, University of Pennsylvania, Philadelphia, PA 19104, USA.
authors.forename: Jennifer N
authors.initials: JN
authors.lastname: Wu
authors.forename: Shereen
authors.initials: S
authors.lastname: Gheith
authors.forename: Natalie A
authors.initials: NA
authors.lastname: Bezman
authors.forename: Qing-Hua
authors.initials: QH
authors.lastname: Liu
authors.forename: Lindsey V
authors.initials: LV
authors.lastname: Fostel
authors.forename: Andrew M
authors.initials: AM
authors.lastname: Swanson
authors.forename: Bruce D
authors.initials: BD
authors.lastname: Freedman
authors.forename: Gary A
authors.initials: GA
authors.lastname: Koretzky
authors.forename: Erik J
authors.initials: EJ
authors.lastname: Peterson
mesh_terms: D048868:Adaptor Proteins, Signal Transducing / Q000172:deficiency / Q000235:genetics / Q000502:physiology*; D000595:Amino Acid Sequence; D000818:Animals; D000938:Antigen-Presenting Cells / Q000276:immunology / Q000378:metabolism; D015704:CD4 Antigens / Q000096:biosynthesis; D016827:CD8 Antigens / Q000096:biosynthesis; D002118:Calcium / Q000378:metabolism; D002448:Cell Adhesion / Q000235:genetics / Q000276:immunology; D015550:Cell Degranulation / Q000235:genetics / Q000276:immunology; D002454:Cell Differentiation / Q000235:genetics / Q000276:immunology*; D045744:Cell Line, Tumor; D049109:Cell Proliferation; D005260:Female; D018655:Lymphocyte Count; D008297:Male; D051379:Mice; D018345:Mice, Knockout; D008822:Mice, Transgenic; D008969:Molecular Sequence Data; D016176:T-Lymphocyte Subsets / Q000166:cytology / Q000276:immunology* / Q000378:metabolism*; D013950:Thymus Gland / Q000166:cytology / Q000276:immunology* / Q000378:metabolism*
chemical_list: D048868:Adaptor Proteins, Signal Transducing; D015704:CD4 Antigens; D016827:CD8 Antigens; C491468:Fyb protein, mouse; D002118:Calcium