Natural killer cell

Pronunciation

Definition 1

A type of immune cell that has granules (small particles) with enzymes that can kill tumor cells or cells infected with a virus. A natural killer cell is a type of white blood cell. Also called NK cell and NK-LGL. (NCI Dictionary)

Definition 2

Natural killer cells are cells that resemble large granular lymphocytes. They do not express markers of either T or B cell lineage. They are positive for CD16, CD56, and CD 94. These cells do possess Fc receptors for IgG and can kill target cells using antibody-dependent cell-mediated cytotoxicity. They can also use perforin to kill cells in the absence of antibody and killing may occur without previous sensitization. (NCI Thesaurus)

Definition 3

Cells responsible for spontaneous cytotoxicity of a variety of tumor cells without prior immunization. These natural killer cells are found in non-immune humans and experimental animals and are thought by some to be the same as KILLER CELLS (killing by antibody-dependent cell cytotoxicity), but they can also kill in the absence of antibody. (NLM, Medical Subject Headings)

Definition 4

NK cells. A type of white blood cell that contains granules with enzymes that can kill tumor cells or microbial cells. Also called large granular lymphocytes. (NCI Dictionary)

Definition 5

White blood cells that attack tumor cells and body cells that have been invaded by foreign substances. (NCI Dictionary)

Definition 6

type of cytotoxic leukocytes which attack and kill virus-infected or neoplastic cells independent of antibody coating or MHC restriction; may be derived from lymphocytes or monocytes. (NIH CRISP Thesaurus)