Creation of rescue system for potential oocytes by apoptosis inhibitory factor gene transfer and xenotransplantation techniques

在哺乳动物中，成年卵巢中含有数十万个卵母细胞，并且在每个发情周期中，小部分卵母细胞重新开始减数分裂。99%以上的卵泡以闭锁的方式再生，但选择排卵卵母细胞的分子调控机制是获得优良后代的重要策略，目前尚未阐明。本研究旨在阐明调节猪卵巢选择性杀死卵泡的分子控制机制，换句话说，检查颗粒细胞中细胞凋亡调节的分子机制。分析了颗粒细胞凋亡信号的传递系统。发现颗粒细胞是一种II型凋亡细胞，凋亡信号通过线粒体传递。我发现了一种新的可溶性受体，一种细胞膜外因子，抑制了Garnulosa细胞的细胞死亡。此外，我证明了两种抑制剂，cFLIP和XIAP，中断细胞内的凋亡信号。为了应用这些凋亡抑制因子，我通过凋亡抑制因子基因转移和异种移植技术建立了冷冻小卵巢组织中潜在卵母细胞的拯救系统，以提高卵泡存活率。

In mammals, hundreds of thousands of oocytes are contained in adult ovaries, and small part of oocytes restart meiosis in each estrous cycle. More than 99% of follicles are regenerated as atresia, however, molecular control mechanism to select ovulating oocytes which is an important strategy to get excellent offspring has not been revealed. The present study performed to elucidate the molecular control mechanism that regulates a selective killing of ovarian follicles in porcine ovaries, in other words, to examine the apoptosis regulating molecular mechanism in granulosa cells. I analyzed the transmission system of apoptotic signal in granulosa cells. I revealed that granulosa cell was a type II apoptosis cell in which apoptotic signal transduced via mitochondria. I found that a novel soluble receptor, an outside factor of cell membrane, inhibited cell death in garnulosa cells. Moreover, I demonstrated two inhibitors, cFLIP and XIAP, which interrupted apoptotic signaling within the cells. For application of these apoptosis inhibiting factors, I created the rescue system for potential oocytes in frozen small ovarian tissues by apoptosis inhibitory factor gene transfer and xenotransplantation techniques to raise the follicle survival rate.