Objective: To investigate the effects of Glycyrrhizae Radix et Rhizoma polysaccharide (GP) on gamma delta T(γδT) cells isolated from human peripheral blood. Method: Peripherals blood mononuclear cells(PBMCs) were obtained from peripheral blood of healthy donors by density gradient centrifugation on Ficoll-Hypaque. γδT cells were amplified from PBMCs by IPP. Then γδT cells were treated with different concentrations of GP (final concentrations: 25

50

100 mg·L-1). CCK-8 assay was performed to measure the proliferation of γδT cells; ELISA assay was used to detect the concentrations of information-γ(IFN-γ) and tumor necrosis factor -α(TNF-α) secreted by γδT cells; cell counting kit 8(CCK-8) assay was performed to measure the cytotoxicity of γδT cells. Result: The results showed that GP could promote γδT cells proliferation in a dose-dependent manner; GP could also remarkably promote γδT cells to secrete IFN-γ and TNF-α (P<0.01); moreover

after being treated with GP

cytotoxicity of γδT cells to HepG2 cells was significantly improved (P<0.05). Conclusion: The results indicated that GP was able to promote proliferation

cytokine secretion and cytotoxicity of γδT cells

which provided new evidences for exploring anti-tumor and immunoregulation mechanism of GP.