title: The enigma of the natural killer cell.
abstract: Natural killer (NK) cells are controlled by receptors specific for polymorphic determinants of class I molecules of the major histocompatibility complex (MHC). The contrasting properties of NK and cytotoxic T cell (CTL) class I receptors provide complementarity in the cytolytic lymphocyte response to viruses, tumours and transplants. Whereas human NK cell class I receptors consist of immunoglobulin domains, their mouse counterparts resemble C-type lectins. This difference may reflect the receptors' diverse and rapidly evolving class I ligands.
mesh_terms: D000818:Animals; D015395:Histocompatibility Antigens Class I / Q000276:immunology; D006801:Humans; D007694:Killer Cells, Natural / Q000276:immunology* / Q000378:metabolism; D037102:Lectins; D051379:Mice; D011948:Receptors, Antigen, T-Cell / Q000276:immunology; D013602:T-Lymphocytes, Cytotoxic / Q000276:immunology / Q000378:metabolism
chemical_list: D015395:Histocompatibility Antigens Class I; D037102:Lectins; D011948:Receptors, Antigen, T-Cell