目的观察载脂蛋白BmRNA编辑酶催化多肽样3G(APOBEC3G)在不同慢性乙型肝炎病毒(HBV)感染类型患者的外周血单个核细胞(PBMC)及肝组织中的表达水平及其细胞内定位。方法用Westernblot及激光扫描共聚焦显微镜,以健康人为对照,检测不同慢性HBV感染类型患者(慢性乙型肝炎、慢性乙型重型肝炎、肝炎肝硬化、HBV相关性肝癌)的PBMC及肝组织中APOBEC3G的表达状况及其亚细胞定位。多组比较采用方差分析,两两比较采用q检验。结果Western blot结果显示,健康人PBMC中APOBEC3G表达水平极低,慢性乙型肝炎、慢性乙型重型肝炎、肝炎肝硬化和HBV相关性肝癌患者PBMC中APOBEC3G蛋白相对表达水平倍数分别为4.12±0.21、4.07±0.28、4.16±0.36、4.21±0.39,均高于健康人。但不同慢性HBV感染类型患者之间两两比较,PBMC中APOBEC3G的表达水平差异无统计学意义(g值分别为0.931、0.744、1.675、1.675、2.606、0.931,P值均〉0.05)。慢性乙型肝炎患者与HBV相关性肝癌患者比较,肝组织中APOBEC3G表达水平差异无统计学意义(4.40±0.34与4.34±0.43,q=0.588,P〉0.05)。激光扫描共聚焦显微镜观察结果显示PBMC中或肝组织中APOBEC3G表达定位于胞质中,胞核中无表达。结论慢性HBV感染患者虽有APOBEC3G的表达升高,可能只是HBV慢性感染的伴随表现,APOBEC3G是否参与机体抵御HBV感染的过程尚不清楚。
Objective To study the expression level and intracellular localization of APOBEC3G in peripheral blood mononuclear cells (PBMCs) and liver tissues of chronic HBV patients. Methods The expression level and intracellular localization of APOBEC3G in PBMCs and liver tissues were detected using the western blot and confocal laser scanning microscope (CLSM). Results Western-blot showed that the expression level of APOBEC3G in PBMCs of healthy controls was very low. The relative expression levels of APOBEC3G in PBMC of patients with chronic hepatitis B, chronic severe hepatitis, liver cirrhosis, or liver cancer were 4.12 ± 0.21, 4.07 ±0.28, 4.16 ± 0.36 or 4.21 ± 0.39 respectively, which were higher than that in the healthy controls. However, there was no significant difference in APOBEC3G expression among differ- ent chronic HBV patients (q = 0.931, 0.744, 1.675, 1,675, 2.606 or 0.931, respectively, all P values 〉0.05). In addition, there was no significant difference on APOBEC3G in liver tissues between chronic hepatitis B patients and hepatocellular carcinoma patients (4.40 ± 0.34 vs 4.34 ± 0.43, q = 0.588, P 〉 0.05). CLSM indicated that the localization of APOBEC3G protein was in cytoplasm of PBMCs and hepatocytes. Conclusion APOBEC3G is upregulated in the PBMCs of chronic hepatitis B patients.