猪苓多糖通过Toll样受体4对小鼠骨髓来源树突状细胞作用研究

目的研究猪苓多糖(Polyporus umbellatus polysaccharides,PPS)活化小鼠骨髓来源树突状细胞(bone marrow dendritic cells,BMDC)功能调节的作用机制,进一步阐明PPS的免疫学活性机制。方法以3H-TdR掺入法、ELISA及流式细胞术检测BMDC表型和功能的各项指标。结果 PPS刺激小鼠BMDC表达CD11c、CD86及白细胞介素-12、-10(IL-12、IL-10)产生,并且具有剂量依赖效应。另外,较阴性对照组,经PPS诱导成熟的BMDC其活化初始T细胞的能力显著提高而吞噬能力显著下降。抗小鼠Toll样受体4(TLR4)单抗可抑制PPS刺激BMDC产生IL-12 p40及阻断荧光标记猪苓多糖(fluorescence-labeled PPS,f-PPS)与BMDC的结合,而抗TLR2及补体受体3(CR3)单抗却无此效应。结论 PPS可经TLR4活化小鼠BMDC发挥免疫调节活性。

Effect of Polyporus umbellatus polysaccharides on activation of murine bone marrow dendritic cells via Toll-like receptor 4

Objective To explore the mechanism of immunomodulatory activity of Polyporus umbellatus polysaccharides (PPS) on murine bone marrow dendritic cells (BMDC). Methods BMDC phenotype and the function indexes were observed by ³H-TdR incorporation, ELISA, and flow cytometry. Results Compared with the negative group, PPS could increase the co-expression of CD11c and CD86 molecules on dendritic cells (DC) surface and the production of IL-12 and IL-10 in a dose-dependent manner. PPS also enhanced matured BMDC capacity of T cell initial activation and decreased phagocytosis of BMDC. Anti-Toll-like receptor 4 (TLR4), but not anti-TLR2 or complement receptor 3 (CR3) monoclonal antibodies inhibited PPS-induced production of IL-12 p40 and blocked the combination between fluorescence-labeled PPS (f-PPS) and BMDC. Conclusion The data demonstrate that PPS could promote the activation of murine BMDC via TLR4 and maturation of immunomodulationy activity.