中文摘要：

目的：研究人单核细胞系在分化为巨噬细胞及转化为泡沫细胞过程中TOLL样受体4（TLR-4）表达的改变及其机制。方法：体外培养人THP-1单核细胞系，加入佛波酯（PMA）培养48h使其分化为巨噬细胞．后者再加入氧化低密度脂蛋白（ox-LDL）使转化为泡沫细胞．采用免疫细胞化学、蛋白质印迹法和逆转录聚合酶链反应（RT-PCR）方法．检测TLR-4蛋白表达及TLR-4 mRNA表达的水平。结果：在单核细胞分化为H嘴细胞的过程中TLR-4mRNA及蛋白水平提高．差异具有显著性（P〈0．05）；在进一步转化为泡沫细胞过程中，mRNA及蛋白水平又增高，与巨噬细胞相比差异有显著性（P〈0．05）。结论：单核细胞分化为泡沫细胞的过程中TLR-4转录水平上调．蛋白量合成增加．从而可能提高泡沫细胞在动脉粥样硬化中的炎性反应能力。

英文摘要：

Objective： To explore the mechanisms of increased expression of Toll-like receptor 4 （TLR-4） during the formation of foam cells. Methods ： Low density lipoprotein （LDL） was oxidized by incubation with CuCl2. The THP 1 human monocytic leukemia cell line （THP-1） was chosen in our study and cultured in RPMI 1640. The differentiation of THP-1 ceils into maerophages （MP） was induced by phorbol myristate acetate （PMA） for 48 h. The MP ceils were then incubated with oxidized LDL （ox-LDL） to generate foam ceils （FC）. The mRNA and the protein mass levels of TLR-4 were determined by immunoeytoehemistry. Western blotting and reverse transcription polyrnerase chain reaction （RT-PCR） in all three groups respectively. Results：The TLR-4 mRNA and the protein mass level were significantly increased not only during the differenciation of monocytes into macrophages （P〈0. 05 ） but also during the formation of lipid-laden foam cells （P〈0. 05 ）. Conclusion： The up regulation of TLR-4 gene expression during the differentiation of monocytes into rnacrophages and the differentiation of macrophages into foam ceils can increase TLR-4 protein synthesis dramatically, which may be closely related to ability of form scell＇s inflamma tion reaction in atherosclerosis.