B19病毒VP1u蛋白对胎鼠心脏的影响

Pathogenic effects of B19 VPlu protein on heart of fetal mice

目的探讨B19病毒vplu蛋白是否影响心脏发育及相关机制。方法对不同孕龄母鼠注射B19病毒vplu蛋白,采集胎鼠心脏组织标本,通过光镜、电镜、免疫组织化学、TUNEL和原位杂交技术观察心脏细胞结构变化、细胞凋亡及相关基因或表面标志物变化。结果实验期间有23只小鼠怀孕,vplu蛋白和(或)抗vplu蛋白mAh干预组与对照组均未见胎鼠流产。各组产仔数量及鼠心脏重量进行组间方差分析,差异无显著性(P>0.05)。vplu蛋白和(或)抗VPIu蛋白mAl干预组光镜下均可见心肌细胞间隙增宽,胞质透明淡染,部分心肌细胞脂肪变性。电镜下vplu蛋白(或)和vplu蛋白mAh共同注射组、抗VPIu蛋白mAb注射组均可见线粒体聚集在增宽的心肌细胞间隙中,有空泡化,并TUNEL免疫荧光和免疫组织化学显示心肌细胞发生细胞凋亡。对照组胎鼠均未见异常。结论B19病毒vplu蛋白与胎鼠流产、心脏发育畸形无关,与胎鼠心脏水肿有关。

Objectives To explore the pathogenic effects of B19 VPIu protein on heart development and its probable mechanisms.Methods B19 VPlu protein was injected into mice at different gestational age,then the cardiac tissue specimens of fetal mice were harvested.The structural changes of cardiac cells were observed by light microscope and electron microscope.Cell apoptosis and surface biomarkers were detected by immunohistochemistry,TUNEL and in situ hybridization techniques.ResultsThere were 23 pregnant mice and no fetal abortion in VPIu protein group,VPlu protein mAh intervention group or control group during the experiment.Heart weight and the number of descendants in each group were analyzed by variance,which shows no statistical difference with P>0.05.Widened myocardial cell gaps,transparent or pale cytoplasm and cardiac steatosis were detected by light microscope in the groups of VP1u protein group and VPIu protein mAb intervention group.Mitochondria with vacuolation gathered in the widened gaps between myocardial cells,and cardiac cell apoptosis were detected by immunohistochemical and immunofluorescence techniques,while there was no abnormalities in control group.Conclusion B19 VPIu protein has no effects on fetal abortion and fetal heart malformation,hut is associated with cardiac edema of fetal mouse.