Bone marrow-derived lymphocytes that possess cytotoxic properties, classically directed against transformed and virus-infected cells. Unlike T CELLS; and B CELLS; NK CELLS are not antigen specific. The cytotoxicity of natural killer cells is determined by the collective signaling of an array of inhibitory and stimulatory CELL SURFACE RECEPTORS. A subset of T-LYMPHOCYTES referred to as NATURAL KILLER T CELLS shares some of the properties of this cell type.

Synonyms: NK Cell, Natural Killer Cells, Killer Cells, Natural, Cell, NK, Cells, NK, NK Cells, Natural Killer Cell, Killer Cell, Natural, Cell, Natural Killer, Cells, Natural Killer