title: Natural-killer cells and dendritic cells: "l'union fait la force".
abstract: Several recent publications have focused on the newly described interactions between natural-killer (NK) cells and dendritic cells (DCs). Activated NK cells induce DC maturation either directly or in synergy with suboptimal levels of microbial signals. Immature DCs appear susceptible to autologous NK-cell-mediated cytolysis while mature DCs are protected. NK-cell-induced DC activation is dependent on both tumor necrosis factor-alpha (TNF-alpha)/interferon-gamma (IFN-gamma) secretion and a cell-cell contact involving NKp30. In vitro, interleukin-12 (IL-12)/IL-18, IL-15, and IFN-alpha/beta production by activated DCs enhance, in turn, NK-cell IFN-gamma production, proliferation, and cytotoxic potential, respectively. In vivo, NK-cell/DC interactions may occur in lymphoid organs as well as in nonlymphoid tissues, and their consequences are multiple. By inducing DC activation, NK-cell activation induced by tumor cells can indirectly promote antitumoral T-cell responses. Reciprocally, DCs activated through Toll-like receptors (TLRs) induce potent NK-cell activation in antiviral responses. Thus, DCs and NK cells are equipped with complementary sets of receptors that allow the recognition of various pathogenic agents, emphasizing the role of NK-cell/DC crosstalk in the coordination of innate and adaptive immune responses.
authors.affiliation: Centre d'Immunologie de Marseille-Luminy, INSERM-CNRS-Univ. Méditerranée, Campus de Luminy, Marseille, France. walzer@ciml.univ-mrs.fr
authors.forename: Thierry
authors.initials: T
authors.lastname: Walzer
authors.forename: Marc
authors.initials: M
authors.lastname: Dalod
authors.forename: Scott H
authors.initials: SH
authors.lastname: Robbins
authors.forename: Laurence
authors.initials: L
authors.lastname: Zitvogel
authors.forename: Eric
authors.initials: E
authors.lastname: Vivier
mesh_terms: D000818:Animals; D000970:Antineoplastic Agents / Q000494:pharmacology; D002450:Cell Communication; D049109:Cell Proliferation; D018925:Chemokines / Q000378:metabolism; D016207:Cytokines / Q000378:metabolism; D003713:Dendritic Cells / Q000166:cytology*; D006801:Humans; D007107:Immune System; D007371:Interferon-gamma / Q000378:metabolism; D007694:Killer Cells, Natural / Q000166:cytology*; D008214:Lymphocytes / Q000166:cytology; D051379:Mice; D008954:Models, Biological; D009369:Neoplasms / Q000276:immunology / Q000628:therapy; D013601:T-Lymphocytes / Q000378:metabolism; D014409:Tumor Necrosis Factor-alpha / Q000378:metabolism
chemical_list: D000970:Antineoplastic Agents; D018925:Chemokines; D016207:Cytokines; D014409:Tumor Necrosis Factor-alpha; D007371:Interferon-gamma