目的 探讨乙型肝炎病毒(HBV)对载脂蛋白B(ApoB)表达的影响,并探讨其调节机制.方法 采用RT-PCR和Western blot法检测HepG2和HepG2.2.15中ApoB mRNA和蛋白的表达,全自动生化分析仪Olympus 5400检测HBV患者和健康对照者ApoB血清学水平,分析健康对照者、慢性乙型肝炎、肝纤维化和肝癌患者中ApoB表达水平的差异,将HBV感染性克隆pHBV1.3转染HepG2细胞,RT-PCR和Western blot法检测ApoB和微粒体甘油三酯转移蛋白(MTP)表达水平的变化.结果 HepG2.2.15细胞中ApoB mRNA和蛋白的表达水平较HepG2低;ApoB在慢性乙型肝炎患者和肝纤维化患者的血清学水平明显低于健康对照者(P<0.05);HBV能够在mRNA和蛋白水平抑制ApoB和MTP的表达.结论 HBV可能通过抑制MTP的表达抑制ApoB的合成和分泌.
Objective To explore the effect of hepatitis B virus(HBV) on the expression of apolipoprotein B(ApoB) and its regulatory mechanism. Methods mRNA and protein expression of ApoB in HepG2 and HepG2.2.15 cells was measured by RT-PCR and Western blot, serum ApoB levels in patients with HBV infection and in healthy individuals were measured by biochemical analyzer Olympus 5400, the expression of ApoB difference among healthy individuals, patients with chronic hepatitis B, liver cirrhosis, and hepatocellular carcinoma were analyzed, HBV infectious clone pHBV1.3 was tranfected into HepG2 cells,and expression of ApoB and microsomal triglyceride transfer protein(MTP) was measured by RT-PCR and Western blot. Results Expression of ApoB mRNA and protein was lower in HepG2.2.15 cells than in HepG2 cells, serum apoB levels was much lower in patients with chronic hepatitis B and liver cirrhosis as compared to healthy individuals( P 〈0.05 ), HBV could inhibit the expression of ApoB and MTP at mRNA and protein levels. Conclusion HBV may downregulate the synthesis and secretion of ApoB via inhibits the expression of MTP.