title: Melanoma cells interfere with the interaction of dendritic cells with NK/LAK cells.
abstract: Dendritic cells (DCs) and natural killer (NK) cells are key players at the interface between innate resistance and acquired immunity. NK cells can induce DC maturation, a differentiation process whereby DCs respond to a environmental stimulus and acquire the ability of eliciting adaptive immunity. Conversely, maturing DCs promote NK functions in vivo and in vitro. This interplay has important consequences on the immune response to pathogens and possibly to neoplastic cells. Here, we show that B16 melanoma cells actively modulate the interaction between DCs derived from bone marrow precursors and NK/LAK cells propagated from the spleen of C57BL/6 mice. DCs increased in a dose-dependent manner the ability of NK/LAK cells to kill melanoma cells and to produce cytokines. This activatory cross-talk entailed the production of IL-18 by DCs and of IFN-gamma by NK/LAK cells. Melanoma cells were not a passive target of NK activity; they regulated the outcome of the interaction between DCs and NK/LAK cells, inhibiting the in vitro production of cytokines as effectively as the genetic deletion of IL-18 or IFN-gamma. Interference with the NK/DC interaction possibly represents a mechanism used by growing tumors to evade the immune response.
authors.affiliation: Department of Oncology, Cancer Immunotherapy and Gene Therapy Program, Clinical Immunology Unit, H San Raffaele Scientific Institute & Vita-Salute San Raffaele University, Milano, Italy.
authors.forename: Annalisa
authors.initials: A
authors.lastname: Capobianco
authors.forename: Patrizia
authors.initials: P
authors.lastname: Rovere-Querini
authors.forename: Claudio
authors.initials: C
authors.lastname: Rugarli
authors.forename: Angelo A
authors.initials: AA
authors.lastname: Manfredi
mesh_terms: D000818:Animals; D002450:Cell Communication; D045744:Cell Line, Tumor; D018920:Coculture Techniques; D003601:Cytotoxicity Tests, Immunologic; D003713:Dendritic Cells / Q000166:cytology / Q000276:immunology / Q000378:metabolism*; D005260:Female; D007371:Interferon-gamma / Q000235:genetics / Q000378:metabolism; D020382:Interleukin-18 / Q000235:genetics / Q000378:metabolism; D015979:Killer Cells, Lymphokine-Activated / Q000166:cytology / Q000276:immunology / Q000378:metabolism*; D007694:Killer Cells, Natural / Q000166:cytology / Q000276:immunology / Q000378:metabolism*; D008297:Male; D008545:Melanoma / Q000276:immunology / Q000378:metabolism* / Q000473:pathology; D051379:Mice; D008810:Mice, Inbred C57BL; D018345:Mice, Knockout; D013997:Time Factors; D014409:Tumor Necrosis Factor-alpha / Q000378:metabolism
chemical_list: D020382:Interleukin-18; D014409:Tumor Necrosis Factor-alpha; D007371:Interferon-gamma