先天性感染人巨细胞病毒小鼠肝脏损伤模型的建立

A mouse model of congenital human cytomegalovirus infection that induces liver damage in new born mouse

目的:建立人巨细胞病毒(human cytomegalovirus,HCMV)先天性感染肝脏损伤的小鼠模型,为研究HC-MV感染性疾病及抗HCMV药物的筛选提供实验基础。方法:取健康纯系清洁级10周龄Balb/c鼠24只,雌雄各半,随机分为3组,每组4对。A、B两组为感染组,将6.0 logTCID50HCMV-AD169病毒悬液按1.0 ml/只接种至小鼠腹腔后雌雄交配。另一组为空白对照组,雌雄小鼠腹腔注射DMEM1.0 ml/只后交配。各组所生新生鼠分别于产后1和10天处死,取肝脏进行病毒分离、病理学检查和荧光定量PCR检测。结果:A、B两组新生鼠肝组织匀浆上清液中分离出HCMV;病理学证实肝组织有炎性改变,肝细胞浊肿、空泡变性,细胞内有特异性HCMV包涵体,部分肝细胞呈坏死表现;HCMV DNA载量分别为7.849 3×107拷贝数/50 mg、5.908 1×107拷贝数/50 mg,两组差异无统计学意义(P>0.05);对照组所生鼠肝组织各项检测未见变化。结论:HCMV可以通过胎盘造成新生鼠的先天性感染,导致肝脏损伤,生后1天和10天的新生鼠感染的病毒载量无明显变化。该模型的建立为人类先天性HCMV感染致肝脏损伤的病理过程以及对先天性感染的干预、诊断和抗病毒药物的筛选提供了可能。

Objective： To explore the human cytomegalovirus（HCMV） congenital infection liver damage mechanism and establish the HCMV congenital infection newborn mouse model.Methods： Twenty four 10 weeks SPF Balb/c mice（half of mice were female）were randomly divided into three groups.One group had four pairs.HCMV-AD169（6.0 logTCID50 in 1 ml/mouse）was injected into the intraperitoneum of group A and B.DMEM（1 ml/mouse）was injected into the intraperitoneum of group control.Then,these mice were used for mating.The newborn mice of group A,B and control were respectively be killed in 1 and 10 days after production.Liver was obtained for virus isolation,pathological study and fluorescence quantitative PCR of detection.Results： HCMV could be isolated from the supernatant of A and B group tissue.Pathological changes in liver consist of swollen vacuoles degeneration and destroyed nuclei of hepatocytes and distinct intranuclear inclusion in hepatocytes with a cellular infiltrates of predominantly phagocytic cells.The HCMV DNA loading of group A and B were respectively 7.849 3×107copies/50 mg and 5.908 1×107copies/50 mg（P 0.05）.All above were not found in control group.Conclusion： The primary maternal HCMV infection during pregnancy could induce congenital infection in fetus by transplacental transmission.The viral load of different periods of HCMV infection had no significant change.The newborn mouse model will provide the study on pathogenesis of congenital HCMV infection in liver and the development of prevention,diagnosis and antiviral drugs for congenital HCMV infection.