枸杞多糖对荷瘤小鼠肿瘤微环境T淋巴细胞亚群及树突状细胞的影响

目的:研究枸杞多糖(Lycium barbarum polysaccharide,LBP)对荷瘤小鼠体内肿瘤微环境中T淋巴细胞亚群和树突状细胞(dendritic cells,DCs)的影响,探讨LBP对荷瘤机体免疫逃逸的干预作用.方法:用LBP给H22荷瘤小鼠灌胃,连续2周后,测定肿瘤重量,采用流式细胞术检查肿瘤浸润淋巴细胞(tumorinfiltrating lymphocyte,TIL)中T淋巴细胞亚群和DCs的数量,以及协同刺激分子CD80(B7-1)表达的变化.结果:LBP可明显抑制肿瘤细胞的生长,增加肿瘤浸润CD4 、CD8 细胞的数量.LBP高剂量组CD4 和CD8 细胞数量的百分比高于模型组(P＜0.05).LBP低剂量和高剂量组肿瘤浸润DCs数量及B7-1表达均较模型组升高,但差异无统计学意义.结论:LBP的抗肿瘤作用可能与恢复荷瘤小鼠TIL中CD4 、CD8 的细胞数量、解除机体的免疫抑制状态及增强机体的抗肿瘤免疫功能有关.LBP能否恢复荷瘤机体DCs的表型及功能尚待进一步研究.

Effects of Lycium barbarum polysaccharide on tumor microenvironment T-lymphocyte subsets and dendritic cells in H22-bearing mice

Objective: To study the effects of Lycium barbarum polysaccharide (LBP) on tumor microenvi ronment T-lymphocyte subsets and dendritic cells in H22-bearing mice and the mechanisms for intervention of tumor immune escape by LBP. Methods: H22-bearing mice were given LBP orally for two weeks. T-lymphocyte subsets and the phenotypes of dendritic cells in tumor-infiltrating lymphocytes (TIL) were detected by flow cytometry (FCM). Results: LBP could significantly increase the numbers of CD4+ and CD8+ T cells in TIL as compared with those in model control group (P<0. 05). In model control group, the number of dendritic cells in tumor microenvironment decreased markedly, while in LBP-treated group, the increased number of dendritic cells and B7-1 expression were observed, but there were no significant differences between these two groups. Conclusion: LBP has anti-tumor effect probably by increasing the numbers of CD4+ and CD8+ T cells in TIL to relieve the immunosuppression and enhance the anti-tumor function of the immune system. But whether LBP can recover the phenocyte and function of dendritic cells in H22-bearing mice should be further studied.