人参皂苷Rb1与黄芪协同逆转肝癌免疫抑制的实验研究

目的探讨人参皂苷Rb1与黄芪协同应用逆转肝癌细胞抑制NK细胞免疫功能的效果及其机制。方法分别对肝癌细胞(HepG2)进行人参皂苷Rb1、黄芪以及人参皂苷Rb1联合黄芪的预处理,分别收集经过药物作用后HepG2的培养上清,同时收集未经过药物预处理的HepG2的培养上清作为对照。通过ELISA方法检测上清中抑制性细胞因子IL-10的水平;检测比较各种上清对NK细胞胞吐和杀伤功能的影响。结果未经过药物预处理的HepG2的培养上清中含有IL-10,经过人参皂苷Rb1、黄芪以及人参皂苷Rb1联合黄芪的预处理后,HepG2培养上清中的IL-10水平下降,以联合应用两种药物的效果最为明显(P<0.01)。同时未经过药物预处理的HepG2的培养上清作用于NK细胞后显著抑制其胞吐和杀伤功能;而经过人参皂苷Rb1、黄芪以及人参皂苷Rb1联合黄芪的预处理后,HepG2的培养上清对于NK细胞的胞吐和杀伤功能的抑制减轻,以联合应用两种药物的效果最为明显(P<0.01)。结论肝癌细胞(HepG2)可能通过分泌抑制性细胞因子IL-10下调NK细胞的胞吐,减少其释放杀伤介质,从而达到抑制免疫的作用。而人参皂苷Rb1以及黄芪能够拮抗HepG2对NK细胞的免疫抑制,而且两者合用有协同效果,从而提高机体的抗肿瘤免疫。

Objective To explore the synergistic antagonistic effect ofginsenoside Rbl and astragalus mongholicus Bge （AMB） on hepatocellular carcinoma cell line HepG2-induced immunosuppression on natural killer （NK） cells. Methods HepG2 were pre-treated with ginsenoside Rbl, AMB or ginsenoside Rbl and AMB. The HepG2 without any pre-treatment was used as a control. Then the cultured supematants of HepG2 were collected and the levels of IL-10 in the supernatants were measured by ELISA respectively. Furthermore, the effects of the collected supernatants on the exocytosis as well as cytotoxicity of NK cells were assessed.Results IL-10 could be detected in the cultured supematant of HepG2 without any pre- treatment. However, ginsenoside Rb 1, AMB as well as ginsenoside Rb 1 and AMB pre-treated HepG2 secreted decreased levels of IL-10 in the cultured supematants respectively. And the HepG2 with the combination pre-treatment of ginsenoside Kbl and AMB secreted the significantly lowest level of IL-10 when compared with that of other groups （P〈0.01）. Furthe/more, the collected supematant of HepG2 showed inhibitory effects on the exocytosis and cytotoxicity of NK cells. However, the down-regulated effects of HepG2 supematant could be significantly reversed when HepG2 were pre-treated with ginsenoside Rbl or AMB. And the antagonistic effect was significantly strongest when HepG2 was pre-treated with both of ginsenoside Rbl and AMB （P〈0.01）. Conclusion HepG2 secreted IL-10 spontaneously which was suggested to participate in the suppression of exocytosis as well as the cytosoxicity of NK cells. Ginsenoside Rbl and AMB could reverse the immunosuppression effects. And the combination usage of them was synergistic in up-regulating the anti-tumor function of NK cells.