natural killer cells


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 cells

A 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).