title: Role for glycogen synthase kinase-3 in NK cell cytotoxicity and X-linked lymphoproliferative disease.
abstract: NK cells from individuals with X-linked lymphoproliferative (XLP) disease exhibit functional defects when stimulated through the NK receptor, 2B4 (CD244). These defects are likely a consequence of aberrant intracellular signaling initiated by mutations of the adaptor molecule SLAM-associated protein. In this report, we show that NK cells from individuals with XLP but not healthy individuals fail to phosphorylate and thereby inactivate glycogen synthase kinase-3 (GSK-3) following 2B4 stimulation. Lack of GSK-3 phosphorylation prevented the accumulation of the transcriptional coactivator beta-catenin in the cytoplasm and its subsequent translocation to the nucleus. Potential signaling pathways leading from 2B4 stimulation to GSK-3 phosphorylation were also investigated. Ligation of 2B4 resulted in the phosphorylation of the guanine nucleotide exchange factor, Vav-1, and subsequent activation of the GTP-binding protein Rac-1 (but not Ras) and the serine-threonine kinase Raf-1 in healthy but not XLP-derived NK cells. In addition, the activity of MEK-2 (but not MEK-1) was up-regulated, and Erk1/2 was phosphorylated in normal NK cells but not those from an individual with XLP suggesting that these proteins relay SLAM-associated protein-dependent signals from 2B4. Finally, inactivation of GSK-3 using a specific inhibitor of GSK-3beta increased the cytotoxicity and cytokine secretion of both healthy and XLP NK cells. These data indicate that the signaling of 2B4 in NK cells is mediated by GSK-3 and beta-catenin, possibly through a signal transduction pathway that involves Vav-1, Rac-1, Raf-1, MEK-2, and Erk1/2 and that this pathway is aberrant in individuals with XLP.
authors.affiliation: Department of Pathology and Laboratory Medicine, British Columbia's Children's Hospital and University of British Columbia, Vancouver, British Columbia, Canada.
authors.forename: Ala
authors.initials: A
authors.lastname: Aoukaty
authors.forename: Rusung
authors.initials: R
authors.lastname: Tan
mesh_terms: D021581:Active Transport, Cell Nucleus; D015703:Antigens, CD / Q000378:metabolism; D018797:Cell Cycle Proteins / Q000378:metabolism; D002460:Cell Line; D003598:Cytoskeletal Proteins / Q000378:metabolism; D003602:Cytotoxicity, Immunologic / Q000187:drug effects; D004791:Enzyme Inhibitors / Q000494:pharmacology; D038362:Glycogen Synthase Kinase 3 / Q000037:antagonists & inhibitors / Q000378:metabolism*; D053804:Granzymes; D006801:Humans; D066298:In Vitro Techniques; D007371:Interferon-gamma / Q000096:biosynthesis; D047908:Intracellular Signaling Peptides and Proteins / Q000235:genetics / Q000378:metabolism; D007694:Killer Cells, Natural / Q000187:drug effects / Q000201:enzymology* / Q000276:immunology*; D008232:Lymphoproliferative Disorders / Q000201:enzymology* / Q000235:genetics / Q000276:immunology*; D020935:MAP Kinase Signaling System; D008562:Membrane Glycoproteins / Q000378:metabolism; D018448:Models, Immunological; D009154:Mutation; D010766:Phosphorylation; D011518:Proto-Oncogene Proteins / Q000378:metabolism; D051567:Proto-Oncogene Proteins c-vav; D011971:Receptors, Immunologic / Q000378:metabolism; D012697:Serine Endopeptidases / Q000096:biosynthesis; D015398:Signal Transduction; D000071179:Signaling Lymphocytic Activation Molecule Associated Protein; D000071176:Signaling Lymphocytic Activation Molecule Family; D015534:Trans-Activators / Q000378:metabolism; D051176:beta Catenin; D020744:rac GTP-Binding Proteins / Q000378:metabolism
chemical_list: D015703:Antigens, CD; C084093:CD244 protein, human; C495270:CTNNB1 protein, human; D018797:Cell Cycle Proteins; D003598:Cytoskeletal Proteins; D004791:Enzyme Inhibitors; D047908:Intracellular Signaling Peptides and Proteins; D008562:Membrane Glycoproteins; D011518:Proto-Oncogene Proteins; D051567:Proto-Oncogene Proteins c-vav; D011971:Receptors, Immunologic; C114953:SH2D1A protein, human; D000071179:Signaling Lymphocytic Activation Molecule Associated Protein; D000071176:Signaling Lymphocytic Activation Molecule Family; D015534:Trans-Activators; C496618:VAV1 protein, human; D051176:beta Catenin; D007371:Interferon-gamma; D038362:Glycogen Synthase Kinase 3; C509213:GZMB protein, human; D053804:Granzymes; D012697:Serine Endopeptidases; D020744:rac GTP-Binding Proteins