title: Combined natural killer cell and dendritic cell functional deficiency in KARAP/DAP12 loss-of-function mutant mice.
abstract: KARAP/DAP12 is a transmembrane polypeptide with an intracytoplasmic immunoreceptor tyrosine-based activation motif (ITAM). KARAP/DAP12 is associated with several activating cell surface receptors in hematopoietic cells. Here, we report that knockin mice bearing a nonfunctional KARAP/DAP12 ITAM present altered innate immune responses. Although in these mice NK cells are present and their repertoire of inhibitory MHC class I receptors is intact, the NK cell spectrum of natural cytotoxicity toward tumor cell targets is restricted. KARAP/DAP12 loss-of-function mutant mice also exhibit a dramatic accumulation of dendritic cells in muco-cutaneous epithelia, associated with an impaired hapten-specific contact sensitivity. Thus, despite its homology with CD3zeta and FcRgamma, KARAP/DAP12 plays a specific role in innate immunity, emphasizing the nonredundancy of these ITAM-bearing polypeptides in hematopoietic cells.
authors.affiliation: Centre d'Immunologie INSERM/CNRS de Marseille-Luminy, France.
authors.forename: E
authors.initials: E
authors.lastname: Tomasello
authors.forename: P O
authors.initials: PO
authors.lastname: Desmoulins
authors.forename: K
authors.initials: K
authors.lastname: Chemin
authors.forename: S
authors.initials: S
authors.lastname: Guia
authors.forename: H
authors.initials: H
authors.lastname: Cremer
authors.forename: J
authors.initials: J
authors.lastname: Ortaldo
authors.forename: P
authors.initials: P
authors.lastname: Love
authors.forename: D
authors.initials: D
authors.lastname: Kaiserlian
authors.forename: E
authors.initials: E
authors.lastname: Vivier
mesh_terms: D048868:Adaptor Proteins, Signal Transducing; D000595:Amino Acid Sequence; D000818:Animals; D000950:Antigens, Ly; D001854:Bone Marrow Cells / Q000276:immunology / Q000378:metabolism; D002460:Cell Line; D002465:Cell Movement / Q000235:genetics / Q000276:immunology; D003433:Crosses, Genetic; D003602:Cytotoxicity, Immunologic / Q000235:genetics*; D003713:Dendritic Cells / Q000276:immunology* / Q000378:metabolism; D004847:Epithelial Cells / Q000276:immunology; D018390:Gene Targeting; D016130:Immunophenotyping; D007694:Killer Cells, Natural / Q000276:immunology* / Q000378:metabolism; D037181:Lectins, C-Type; D008562:Membrane Glycoproteins / Q000096:biosynthesis; D008565:Membrane Proteins; D051379:Mice; D008807:Mice, Inbred BALB C; D008810:Mice, Inbred C57BL; D008808:Mice, Inbred CBA; D018345:Mice, Knockout / Q000276:immunology*; D008822:Mice, Transgenic; D008969:Molecular Sequence Data; D009092:Mucous Membrane / Q000166:cytology / Q000276:immunology; D011971:Receptors, Immunologic / Q000172:deficiency* / Q000235:genetics* / Q000502:physiology; D055630:Receptors, NK Cell Lectin-Like; D017384:Sequence Deletion; D015398:Signal Transduction / Q000235:genetics / Q000276:immunology; D012867:Skin / Q000166:cytology / Q000276:immunology
chemical_list: D048868:Adaptor Proteins, Signal Transducing; D000950:Antigens, Ly; D037181:Lectins, C-Type; D008562:Membrane Glycoproteins; D008565:Membrane Proteins; D011971:Receptors, Immunologic; D055630:Receptors, NK Cell Lectin-Like; C110546:TYROBP protein, human