氧化低密度脂蛋白对THP-1巨噬细胞吞噬和分泌功能的影响

目的:探讨氧化低密度脂蛋白(oxidized low density lipoprotein,ox-LDL)对巨噬细胞源性泡沫细胞吞噬功能和炎症相关因子分泌功能的影响。方法:利用佛波酯(phorbol ester,PMA)诱导THP-1细胞分化形成巨噬细胞,之后采用ox-LDL处理48小时后,诱导其形成泡沫细胞。利用中性红吞噬实验,分析泡沫细胞形成前后吞噬功能的变化;通过ELISA法,检测细胞培养上清中肿瘤坏死因子α(tumor necrosis factorα,TNF-α)含量,观察ox-LDL对THP-1巨噬细胞功能的影响。结果:细胞形态学结果表明,我们成功利用ox-LDL诱导THP-1巨噬细胞形成泡沫细胞;进一步发现ox-LDL诱导THP-1巨噬细胞表面的清道夫受体CD36表达升高,并促进细胞吞噬功能增加,进一步促进细胞内胆固醇含量显著升高(P0.05);同时,ox-LDL能够刺激巨噬细胞大量分泌TNF-α(P0.05)。结论:ox-LDL通过增强清道夫受体CD36表达,提高巨噬细胞的吞噬功能,引起大量胆固醇聚集,产生细胞毒性损伤,并促进TNF-α炎性因子的大量分泌。

Effects of Oxidized Low Density Lipoprotein on the Phagocytosis andSecretion of Macrophage Cells

Objective:To investigate the effect of oxidized low density lipoprotein (ox-LDL) on the phagocytosis and secretoryfunction of the macrophage-derived foam cells.Methods:The phorbol ester (PMA) was used to culture and differentiate Human THP-1cells into macrophages. Afterwards, macrophages were induced 48 hours by the ox-LDL, and turned into foam cells. The change of thephagocytosis function before and after the formation of foam cells was analyzed by the neutral red phagocytosis test, the tumor necrosisfactor alpha(tumor necrosis factor -alpha, TNF-alpha) level was detected by ELISA, and then the effect of ox-LDL on THP -1 macrophage functionwas observed.Results:The THP-1 cells were successfully induced into macrophage foam cells evaluating by Oil red O staining, and furtherox-LDL significantly enhanced the expression of CD36 on the surface of macrophages. The intracellular cholesterol content increasedsignificantly (P<0.05) suggesting that ox-LDL could promote the phagocytic function, meanwhile, ox-LDL also could stimulatemacrophages to secrete some TNF-alpha(P<0.05).Conclusion:By enhancing the expression of CD36, ox-LDLimprove macrophages phagocytosis,leading to a large of cholesterol accumulation, and cytotoxic damage, and promoting inflammatory cytokines secretion such asTNF-alpha.