natural killer cells
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nat·u·ral kill·er cells (NK),
large granular lymphocytes that do not express markers of either T or B cell lineage. These cells do possess Fc receptors for IgG and can kill target cells using antibody-dependent cell-mediated cytotoxicity. NK cells can also use perforin to kill cells in the absence of antibody. Killing occurs without previous sensitization.
Synonym(s): NK cells
natural killer cellsA class of large, granular lymphocytes that bind directly to cells bearing foreign ANTIGENS and kill them. Natural killer cells do not require prior exposure of the immune system to the antigen and kill their victims by programmed cell death (apoptosis).
natural killer cells,
n.pl lymphocytes that are part of innate immunity that kill foreign substances and abnormal tissues. Decreased number or activi-ty has been linked to a number of diseases, including AIDS, cancer, chronic fatigue syndrome, immuno-deficiencies, and viral infections. See also innate immunity.