Natural killer cells

Natural killer (NK) cells have features of both innate and adaptive immunity. They are important for recognizing and killing virus-infected cells or tumor cells. They contain intracellular compartments called granules, which are filled with proteins that can form holes in the target cell and also cause apoptosis, the process for programmed cell death. It is important to distinguish between apoptosis and other forms of cell death like necrosis. Apoptosis, unlike necrosis, does not release danger signals that can lead to greater immune activation and inflammation. Through apoptosis, immune cells can discreetly remove infected cells and limit bystander damage. Recently, researchers have shown in mouse models that NK cells, like adaptive cells, can be retained as memory cells and respond to subsequent infections by the same pathogen.

Source: NIAID (NIH)1

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Killer Cells, Natural: 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.2


Types may include:3

Types of Natural Killer Cell:

  • Activated Natural-Killer Cell
  • Invariant Natural Killer T-Cell

Categories for Natural killer cells

Category of Natural Killer Cell Therapy:

  • Leukocyte Therapy

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  1. Source: NIAID (NIH): topics/ immuneSystem/ Pages/ immuneCells.aspx
  2. Source: MeSH (U.S. National Library of Medicine)
  3. Source: NCI Thesaurus
  4. ibid.
  5. Source: RDCRN (NCATS/NIH): cms/ cegir/ Learn-More/ Glossary

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