The Effect of G2 Adjuvant on Gene Expression and Delivery of NKG2D Receptor on NK Cells in Peripheral Blood

Introduction: Natural killer (NK) cells are a subset of lymphocytes in humans that release cytokines such as tumor necrosis factor alpha and interferon gamma-c during infection. NKG2D is one of the most important stimulating NK receptors binding MIC-A, MIC-B, and ULBPs, which leads to activation of NK cells against tumor cells. In this study, the authors evaluated the effect of G2 adjuvant on gene expression and delivery of NKG2D receptor on NK cells in peripheral blood. Materials and Methods: Peripheral blood mononuclear cells were isolated from venous blood obtained from healthy volunteers after adding G2 adjuvant within 12, 24, and 48 hours of incubation. Then, total RNA was extracted from the cells, cDNA synthesis was performed, and gene expression was evaluated by real-time PCR. In addition, NK cells were stained with the appropriate monoclonal antibodies, and the receptors expressed on cell surface were quantified. Results: G2 adjuvant leads to upregulation of gene expression and increases the expression of NKG2D receptor on the surface of NK cells after incubation. Conclusion: The findings of this study demonstrated that G2 adjuvant can increase NK cell cytotoxicity. It may play an important role in killing tumor cells, preventing tumor growth and metastasis.