Bioreactor Actuated Ovarian Development

描述（由申请人提供）： 卵泡是卵巢的基本单位，提供卵母细胞和雌性发育和生殖所需的类固醇激素。卵泡生长是一个长期的过程，涉及卵泡单位通过特定的组织学定义的发育阶段进行性发育。由于在过去的二十年里，新的不孕症治疗方法和人工生殖技术的出现，我们已经对晚期卵泡发育有了很好的了解。相比之下，我们对卵泡发育的早期阶段知之甚少。最近，世界各地的许多团体已经开始为年轻女孩和接受潜在绝育手术或化疗的妇女进行卵巢冷冻保存计划，希望卵泡可以从这些组织中分离出来，并在以后的日子里在体外生长，当妇女希望怀孕时。由于生长中的卵泡不能在冷冻后存活，因此冷冻保存后仅保留非常小的原始卵泡。虽然来自小鼠的卵泡可以使用传统的培养技术生长成熟，但科学家们在体外培养具有较大卵泡的物种（如大鼠，猪和人类）的卵泡方面一直不成功。因此，目前还没有技术可以利用这些保存的卵巢组织来研究卵泡发育，甚至恢复生育能力。我们最近进行了研究，以确定为什么大鼠卵泡不能在体外发展超过腔前卵泡阶段。我们的初步研究表明，在常规条件下，大鼠卵泡经常发生扁平化和破裂，失去解剖完整性，这对正常的卵子成熟过程很重要。当卵泡在悬浮培养系统中培养时，由轨道试管和内壁容器组成，卵泡不破裂，并表现出更健壮的生长。因此，我们相信，生物反应器技术的进步对开发一种能够支持卵泡发育的复杂需求的系统具有很大的希望。由于缺乏关于早期卵泡发育的知识，这是一个高风险的项目，因为反应器的设计必须是经验性的，而不是基于已知的生物学要求。我们提出，生物工程可以克服卵泡生长，并提供支持早期卵泡生长的解决方案，并建立健康卵泡发育的标志物，可用于微调培养条件，以获得优化的卵泡生长和发育。

DESCRIPTION (provided by applicant): The follicle is the essential unit of the ovary, providing both oocytes and the steroid hormones necessary for female development and reproduction. Follicle growth is a prolonged process that involves progressive development of the follicle unit through specific histologically defined stages of development. Because of the advent of new infertility treatments and artificial reproductive technologies over the last two decades, we have built up an excellent understanding of late-stage follicle development. In contrast, we know very little about the earlier stages of follicle development. Recently many groups around the world have begun ovarian cryopreservation programs for young girls and women undergoing potentially sterilizing surgery or chemotherapy with the hope that follicles can be isolated from these tissues and grown in vitro at a later date, when the woman desires to become pregnant. Since growing follicles do not survive freezing, only the very small primordial follicles remain after cryopreservation. Though follicles derived from mice can be grown up to maturity using conventional culture techniques, scientists have been unsuccessful with the in vitro development of follicles from species that have larger follicles, such as rats, pigs and humans. Therefore there is no current technology in which these preserved ovarian tissues can be utilized to study follicle development or even to restore fertility. We have recently performed studies to determine why rat follicles fail to progress beyond the preantral follicle stage in vitro. Our preliminary studies demonstrated that under conventional conditions, rat follicles frequently undergo flattening and rupture with loss of anatomic integrity that is important to the normal egg maturation process. When follicles were cultured in suspension culture systems, consisting of orbiting test tubes and rotating-wall vessels, the follicles did not rupture and exhibited more robust growth. Therefore we believe that advances in bioreactor technologies hold great promise toward the development of a system that can support the complex needs of the developing follicle. The lack of knowledge surrounding early stage follicle development makes this a high-risk project because reactor design will have to be empirical rather than based on known biological imperatives. We propose that bioengineering can overcome empiricism and provide solutions that support the growth of early stage follicles and establish markers of healthy follicle development that can be used to fine tune culture conditions to obtain optimized follicle growth and development.