ApoAⅠ促进THP-1源性泡沫细胞ApoE分泌的研究

Effect of ApoA I on Secretion of ApoE in Human THP-1 Derived Foam Macrophages

目的通过建立动脉粥样硬化损伤部位细胞模型，观察ApoAI对THP—l源性泡沫细胞ApoE分泌的影响，探讨ApoAI与ApoE之间是否存在相互关系以及这种关系对动脉粥样硬化的影响。方法采用聚乙二醇-6000（PEG-6000）沉淀法制备人血浆HDL，再利用凝胶过滤柱层析法分离ApoA I；佛波酯（PMA）诱导THP-1单核细胞分化为巨噬细胞，氧化型低密度脂蛋白（oxidized low density lipoprotein，OXLDL）使分化后THP-1细胞荷脂，建立动脉粥样硬化细胞模型；ELISA检测不同浓度ApoAI（0，5，10，15，25ug／m1）及不同孵育时间（0．3，6，12，24h），THP—1源性泡沫细胞ApoE的分泌；RT—PCR检测细胞ApoEmRNA的表达情况。结果ApoAI增加THP-1源性泡沫细胞ApoE的分泌量；且ApoE蛋白质的分泌随着ApoAI孵育时间增加而增加，在24hApoE的分泌量达最大；在剂量试验中，ApoE的分泌量随着ApoAI剂量的增加有增加趋势，ApoAI浓度为25μmol／L时，ApoE分泌量最大；而却oE基因的表达不受ApoAI的影响。结论-定浓度的ApoAI促进THP-1源性泡沫细胞ApoE的分泌，且具有时间及剂量依赖性。而在基因水平上，ApoAI对ApoEmRNA表达没有影响。

Objective We hypothesized that interaction between ApoA I and ApoE contributes to the antiatherosclerosis. To this end, we set up the cell models of atherosclerosis to investigate the effects of ApoA I on secretion of ApoE in human THP-1 maerophages. Methods Human plasma HDL was first isolated and purified by PEG-6000 of different density, and ApoA I was then separa- ted with gel-filtration chromatography from the HDL. Human monocyte cell line THP-I was stimula- ted and transformed to macrophages by PMA, then incubated with ox-LDL. To set up the cell mod- els of atheroselerosis, THP-1 macrophages were incubated with ApoA [ at dose range of 0, 5, 10, 15, and 25 g/ml. In the time course experiment, THP-1 macrophages were incubated with 25 g/ml ApoA I for 0, 3, 6, 12, and 24- hours, respeetively. Secretion of ApoE was detected with ELISA. The mRNA level of ApoE was determined by reverse transcription polymerase chain reaction （RT-PCR） . Results ApoA I increased secretion of ApoE out of THP-1 derived foam maeropha- ges. Seeretion of ApoE was increase with the dose range and time eourse, reaehing the highest a- mount correspondingly at the time point of 24 hour incubation with ApoA I and the dose of 25 g/ml ApoA I. The effect of ApoA I on the mRNA of ApoE was not obvious. Conclusion ApoA [ stim- ulates ApoE secretion by THP-1 derived foam macrophages. The amount of ApoE secretion is time- course and dose dependent on ApoA I . But ApoA I has no effect on the mRNA level of ApoE.