Development of Disease Model Mice for Parvovirus-Related Disorder and Pathogenic Mechanism

为了阐明细小病毒相关疾病的致病机制，本文通过体内和体外实验研究了细小病毒NS和调控NS表达的P4启动子的功能。结果如下：1) P4区域的CRE在P4启动子活性中起重要作用，CREB和/或某些反式激活因子是P4启动子激活所必需的细胞因子，尤其是肿瘤细胞。由于在P4启动子下表达EGFP的转基因小鼠中证实了精母细胞特异性EGFP表达，因此增强P4活性的细胞因子似乎存在于精母细胞中。2)建立了四环素诱导的NS过表达转基因小鼠。然而，在这些小鼠中观察到非特异性NS渗漏表达。3)逆转录病毒载体转染ns后，细胞表现出粘附性增强、微绒毛数量增加、对凋亡敏感、致瘤性降低等表型变化，并诱导CNTFR α基因发生表观遗传修饰、组蛋白乙酰化。提示细小病毒NS的表观遗传修饰可能与细小病毒的发病机制及其抗肿瘤活性有关。4)本研究建立了利用小鼠细小病毒序列信息诊断细小病毒感染的新方法。

To elucidate pathogenic mechanisms on parvovirus-related disorder, functions of parvoviral NS and P4 promoter which regulate to expression of NS were examined in vitro and in vivo experiments. The results are as follows.1) CRE on P4 region was important role in its promoter activity, and CREB and/or certain trans-activation factor was suggested to be required to activation of P4 promoter as cellular factors especially in tumor cells. Since Spermatocytes-specific EGFP expression was demonstrated in transgenic mice that express EGFP under P4 promoter, cellular factors that enhance P4 activity seemed to be in spermatocytes.2) Transgenic mice that expected to tetracycline-inducible NS over-expression was developed. However, non-specific leaky expression of NS was observed in these mice.3) The NS-transfected cell with retrovirus vector showed several phenotypic changes such as enhanced cell adherence, increased numbers of micro-villi, sensitivity to apoptosis and decreased tumorgenecity, and was induced epigenetic modification, histone-acetylation in CNTFR α gene. It suggested that a possibility of epigenetic modification with parvovirus NS should be related to parvovirus pathogenesis and its anti-tumor activity.4) New diagnosis method for parvovirus infection was developed using sequence information of mouse parvovirus in this study.