分枝菌酸诱导巨噬细胞源性泡沫细胞模型的建立及鉴定

Establishment and characterization of macrophage-derived foam cell model induced by mycolic acid

目的探讨分枝菌酸(MA)包被聚苯乙烯微球诱导小鼠RAW264.7巨噬细胞泡沫细胞化的条件及特性。方法将RAW264.7细胞分为空白对照组和分别包被(0、25、50、75、100)μg/mL MA的聚苯乙烯微球实验组,分别将细胞与聚苯乙烯微球混匀、共同孵育24、48、72 h、5 d和8 d后,油红O染色后显微镜下观察细胞形态,采用总胆固醇试剂盒和游离胆固醇试剂盒测定各组泡沫细胞内胆固醇酯的含量,采用MTT法检测细胞增殖水平。结果当包被MA浓度为75μg/mL、吞噬时间为24 h时,RAW264.7能形成典型的泡沫细胞,其细胞内胆固醇酯相对含量为60.98%±1.32%;随着吞噬时间延长,形成泡沫细胞所需的MA的浓度逐渐递减;且随着细胞泡沫化程度增加,细胞增殖活力逐渐减弱。结论 MA包被聚苯乙烯微球可快速诱导巨噬细胞形成泡沫细胞,MA浓度与细胞泡沫化程度呈正相关,且有时间依赖性。

Objective To explore the formation conditions and characteristics of murine macrophage-derived foam cells induced by the polystyrene microspheres coated with mycolic acid（ MA）. Methods RAW264. 7 cells were divided into blank control group and polystyrene microsphere experimental groups where polystyrene microspheres were coated with 0,25,50,75 and 100 μg /mL mycolic acid,respectively. The mixture of RAW264. 7 cells and polystyrene microspheres was incubated for 24,48,72 hours,5 and 8 days,respectively. After oil red O staining,the cell morphology of each group was observed under a microscope. The level of intracellular cholesterol ester of each group was measured with total cholesterol and free cholesterol kits,and the cell proliferation was detected with MTT assay. Results When the concentration of MA was 75 μg /mL and the phagocytosis time was 24 hours,the typical foam cells formed,and its intracellular cholesterol ester content was（ 60.98 ±1.32） %. With the phagocytosis time went by,the lower MA concentration was needed for the formation of foam cells. With the gradual accumulation of lipids in foam cells,the cell proliferation activity was gradually weakened. Conclusion MA-coated polystyrene microspheres can quickly induce macrophages to form foam cells. MA concentration and the formation of foam cells were positively correlated,and it is time-dependent.