NK cells and cancer immunosurveillance.
Natural killer (NK) cells are lymphocytes of the innate immune system that monitor cell surfaces of autologous cells for an aberrant expression of MHC class I molecules and cell stress markers. Since their first description more than 30 years ago, NK cells have been implicated in the immune defence against tumours. Here, we review the broadly accumulating evidence for a crucial contribution of NK cells to the immunosurveillance of tumours and the molecular mechanisms that allow NK cells to distinguish malignant from healthy cells. Particular emphasis is placed on the activating NK receptor NKG2D, which recognizes a variety of MHC class I-related molecules believed to act as 'immuno-alerters' on malignant cells, and on tumour-mediated counterstrategies promoting escape from NKG2D-mediated recognition.
Department of Immunology, Interfacultary Institute for Cell Biology, Eberhard Karls University of Tübingen, Tübingen, Germany.
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Waldhauer
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Steinle
D000818:Animals; D058851:GPI-Linked Proteins; D006801:Humans; D007157:Immunologic Surveillance / Q000502:physiology*; D036341:Intercellular Signaling Peptides and Proteins / Q000502:physiology; D007694:Killer Cells, Natural / Q000145:classification / Q000502:physiology*; D008213:Lymphocyte Activation / Q000276:immunology; D008954:Models, Biological; D055655:NK Cell Lectin-Like Receptor Subfamily K; D009369:Neoplasms / Q000276:immunology*; D011971:Receptors, Immunologic / Q000502:physiology; D054340:Receptors, KIR / Q000502:physiology; D055607:Receptors, Natural Killer Cell; D017634:Self Tolerance / Q000276:immunology / Q000502:physiology; D019139:Tumor Escape / Q000276:immunology / Q000502:physiology
D058851:GPI-Linked Proteins; D036341:Intercellular Signaling Peptides and Proteins; C527085:KLRK1 protein, human; D055655:NK Cell Lectin-Like Receptor Subfamily K; D011971:Receptors, Immunologic; D054340:Receptors, KIR; D055607:Receptors, Natural Killer Cell; C423230:ULBP2 protein, human