Natural killer cell

Type of cytotoxic lymphocyte

Natural killer cells, also known as NK cells, are a type of cytotoxic lymphocyte critical to the innate immune system. They are a kind of large granular lymphocyte (LGL), belong to the rapidly expanding family of known innate lymphoid cells (ILC), and represent 5–20% of all circulating lymphocytes in humans. The role of NK cells is analogous to that of cytotoxic T cells in the vertebrate adaptive immune response.

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