Natural killer cell therapy

Natural killer (NK) cells are a unique and the third most common subset of lymphocytes residing in the marrow, spleen, and peripheral blood. Approximately 10 % of lymphocytes in the peripheral blood are NK cells. Phenotypically, NK cells are positive for CD56 and CD16 but negative for CD3.1-3 Unlike T-cells, NK cells kill tumor cells and virally infected cells without previous stimulation and MHC-restriction, and do not express clonally rearranged receptors. NK cell cytotoxicity involves exocytosis of perforin- and granzyme-containing cytoplasmic granules,4 as well as FasL- and TRAIL-mediated pathways.5 NK cells produce various cytokines, notably IFN-gamma, TNF-alpha, GM-CSF, and IL-10.6 NK cells mediate important functions in innate immunity and are capable of eliminating major histocompatibility complex (MHC) class I-deficient virus-infected cells and tumor cells. In addition, NK cells are involved in many autoimmune diseases such as multiple sclerosis, systemic lupus erythematosus, experimental autoimmune encephalomyelitis, and allograft rejection. 대한간학회｜간세포암종 의 새로 운 치료: Systemic therapy 50 NK cells are derived from hematopoietic stem cells (HSCs) in the bone marrow (BM), which is the main site of NK cell generation. The NK cell development from HSCs consists of multiple steps, whic