在病毒性疾病发生过程中，病毒感染与宿主细胞凋亡之间存在着密切关系，一方面病毒通过诱导细胞凋亡引起宿主发病，另一方面宿主通过细胞凋亡来清除病毒。研究表明，PPV可以在胎盘滋养层细胞中复制，阻碍母体对胎儿营养的传递，还能使黄体发生萎缩，使之失去分泌孕酮功能，导致母猪流产或胎儿死亡。本课题组前期成功分离获得一株PPV，并接种于体外培养的猪黄体细胞和胎盘滋养层细胞，结果发现细胞发生了凋亡。然而它是通过何种分子信号转导通路诱导细胞发生凋亡的，至今尚不清楚。本项目以此为切入点，用PPV攻毒初孕母猪，检测黄体和胎盘中细胞凋亡情况，再用PPV感染体外培养的黄体细胞和胎盘滋养层细胞，最后对死亡受体通路、线粒体通路及其上游的p53通路中信号分子进行检测，揭示PPV引起母猪繁殖障碍的发病机制。研究结果不仅为深入探索PPV与宿主细胞之间的互作关系奠定基础，同时也为研究其他病毒引起动物繁殖障碍的发病机制提供新思路。

In the process of viral disease, there is the intimate connection between virus infection and apoptosis of host cells. On one hand, virus induces animal disease through apoptosis, on the other hand, animal body clears virus by apoptosis. Previous studies showed that PPV could not only replicate in the placental trophoblasts and delay the fetuses to obtain nutrient through placenta, but also cause atrophy of corpus luteum and affect the secretion of progesterone, resulting in abortion or fetal death. Our research group isolated a PPV strain, which could induce apoptosis to porcine luteal cells and placental trophoblasts in vitro. However, it remains unclear what signal transduction pathway were involved in apoptosis process induced by PPV. In this project, early pregnant sows will be challenged by PPV, and apoptosis will be detected in the corpus luteum and placent tissues. And then, luteal cells and trophoblasts will be infected with PPV in vitro to illustrate the signal transduction pathway of apoptosis induced by PPV, the signal molecules in death receptor pathway, mitochondrial pathway and their upstream regulated pathways, p53 pathways will be checked to reveal the molecular mechanism of PPV causes reproductive failure of sow. The results will lay the foundation for probing the interaction between PPV and host cells, and provide new guidance for the investigation of molecular mechanism to other virus-induced reproductive failure in animals.