Fucoidan对巨噬细胞RAW264.7的免疫调节作用

Immunomodulatory effects of fucoidan from Undaria pinnatifida sporophyll on macrophage RAW264.7

目的观察褐藻多糖硫酸酯(Fucoidan)对巨噬细胞RAW264.7体外吞噬活性、细胞因子TNF-α和IL-6分泌,以及Toll样受体4(TLR4)mRNA表达的影响。方法实验分对照组,Fucoidan高、中、低剂量组(浓度分别是200、400和800μg/mL)。药物处理6~48h后,MTT法检测RAW264.7细胞活力;中性红比色法检测细胞吞噬活性;ELISA法检测培养上清中TNF-α和IL-6的分泌水平;实时定量PCR检测Toll样受体4(TLR4)mRNA表达量。结果与对照组相比,Fucoidan显著增强RAW264.7细胞代谢活力和吞噬能力(P<0.01),增加TNF-α和IL-6的分泌,上调TLR4的表达,呈剂量依赖关系。结论 Fucoidan可上调TLR4表达,增强巨噬细胞代谢和吞噬活性,增加TNF-α和IL-6的分泌,具有潜在的调节免疫作用。

Objective To observe the effects of fucoidan on phagocytic activity in vitro,secretion of cytokines TNF-αand IL-6,and the mRNA level of toll-like receptor 4（TLR4）in mouse macrophage RAW264.7.Methods The cell viability and phagocytic activity of RAW264.7 treated with fucoidan（at concentrations of0,200,400 and 800μg/mL respectively for 6 to 48 hours）were detected by using MTT and neutral red colorimetry respectively in vitro.The effect of fucoidan on the levels of TNF-αand IL-6 in RAW264.7 cells was assessed with ELISA assay.The mRNA level of TLR4 was tested by using real-time quantitative PCR（RT-PCR）.Results Compared with the control group,fucoidan significantly enhanced the vitality and phagocytosis of RAW264.7 cells（P〈0.01）,increased the secretion of TNF-αand IL-6 and the expression of TLR4 in a dose-dependent manner.Conclusion Fucoidan can significantly increase TLR4 expression,enhance the metabolism and phagocytosis of macrophage RAW264.7,and promote the secretion of TNF-αand IL-6,which has a potential application value in regulating immune imbalance.