title: Association with FcRgamma is essential for activation signal through NKR-P1 (CD161) in natural killer (NK) cells and NK1.1+ T cells.
abstract: Natural killer (NK) cells exhibit cytotoxicity against variety of tumor cells and virus-infected cells without prior sensitization and represent unique lymphocytes involved in primary host defense. NKR-P1 is thought to be one of NK receptors mediating activation signals because cross-linking of NKR-P1 activates NK cells to exhibit cytotoxicity and IFN-gamma production. However, molecular mechanism of NK cell activation via NKR-P1 is not well elucidated. In this study, we analyzed the cell surface complex associated with NKR-P1 on NK cells and found that NKR-P1 associates with the FcRgamma chain which is an essential component of Fc receptors for IgG and IgE. The association between FcRgamma and NKR-P1 is independent of Fc receptor complexes. Furthermore, NK cells from FcRgamma-deficient mice did not show cytotoxicity or IFN-gamma production upon NKR-P1 cross-linking. Similarly, NK1.1+ T cells from FcRgamma-deficient mice did not produce IFN-gamma upon NKR-P1 crosslinking. These findings demonstrate that the FcRgamma chain plays an important role in activation of NK cells via the NKR-P1 molecule.
authors.affiliation: Division of Molecular Genetics, Center for Biological Science, Chiba University School of Medicine, Chiba 260, Japan.
authors.forename: N
authors.initials: N
authors.lastname: Arase
authors.forename: H
authors.initials: H
authors.lastname: Arase
authors.forename: S Y
authors.initials: SY
authors.lastname: Park
authors.forename: H
authors.initials: H
authors.lastname: Ohno
authors.forename: C
authors.initials: C
authors.lastname: Ra
authors.forename: T
authors.initials: T
authors.lastname: Saito
mesh_terms: D000818:Animals; D000950:Antigens, Ly; D000954:Antigens, Surface / Q000378:metabolism / Q000502:physiology*; D007371:Interferon-gamma / Q000096:biosynthesis; D015847:Interleukin-4 / Q000378:metabolism; D007694:Killer Cells, Natural / Q000378:metabolism*; D037181:Lectins, C-Type; D051379:Mice; D008810:Mice, Inbred C57BL; D018345:Mice, Knockout; D055651:NK Cell Lectin-Like Receptor Subfamily B; D017452:Receptors, IgG / Q000378:metabolism / Q000502:physiology*; D011971:Receptors, Immunologic / Q000378:metabolism / Q000502:physiology*; D015398:Signal Transduction; D013601:T-Lymphocytes / Q000378:metabolism*
chemical_list: D000950:Antigens, Ly; D000954:Antigens, Surface; C527211:Klrb1c protein, mouse; D037181:Lectins, C-Type; D055651:NK Cell Lectin-Like Receptor Subfamily B; D017452:Receptors, IgG; D011971:Receptors, Immunologic; D015847:Interleukin-4; D007371:Interferon-gamma