killer cell

Natural killer cells (or NK cells) are a type of cytotoxic lymphocyte which constitute a major component of the innate immune system. NK cells play a major role in the rejection of tumors and cells infected by viruses. The cells kill by releasing small cytoplasmic granules of proteins called perforin and granzyme that cause the target cell to die by apoptosis.
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Noun
1. T cell with CD8 receptor that recognizes antigens on the surface of a virus-infected cell and binds to the infected cell and kill it
(synonym) killer T cell, cytotoxic T cell, CD8 T cell, CD8 cell
(hypernym) T cell, T lymphocyte

A white blood cell that attacks tumor cells and body cells that have been invaded by foreign substances.