Background
Recent studies have focused on the significant cytotoxicity of natural killer (NK) cells, cytokine-induced killer (CIK) cells, and gamma-delta (γδ) T cells in tumor cells. Nevertheless, the therapeutic features of these cell types have not been compared in the literature. The
Conclusions
Expanded NK cells from cancer patients are the most effective immune cells in the context of cytokine secretion and anti-tumor cytotoxicity in comparison to CIK and γδ T cells, making them an optimal candidate for adoptive cellular immunotherapy.
Methods
NK, CIK, and γδ T cells were induced from the peripheral blood mononuclear cells of 20 cancer patients by using specific cytokines. Expression of CD69, NKG2D, CD16, granzyme B, perforin, IFN-γ, and IL-2 was measured by flow cytometry. Cytokine production and cytotoxicity were analyzed by enzyme-linked immunosorbent assay and Calcein-AM methods.
Results
NK cell proliferation was superior to that of CIK cells, but lower than that of γδ T cells. NK cells had a much stronger ability to secrete perforin, granzyme B, IFN-γ, and IL-2 than did CIK and γδ T cells, and imparted significantly higher overall cytotoxicity. Conclusions: Expanded NK cells from cancer patients are the most effective immune cells in the context of cytokine secretion and anti-tumor cytotoxicity in comparison to CIK and γδ T cells, making them an optimal candidate for adoptive cellular immunotherapy.