MARKER ASSISTED SELECTION OF BOVINE BLASTOCYSTS

描述(改编自申请人的摘要)：本研究的目标 是为了研究利用标记辅助选择的可能性 移植后优质胚胎将提高妊娠率 体外衍生的囊胚。这样的战略可能会产生重大影响 关于人类生育问题的治疗，怀孕率 经过体外受精和早期胚胎移植 仍远低于25%。一项可行性的调查研究 分子标记辅助胚胎选择需要大量的胚胎和 受控条件下的受助人，不太可能达到的标准 用于人类胚胎。因此，建议使用沙门氏菌分泌物 以牛胚泡为模型系统检测干扰素-tau 由单个胚胎产生的蛋白质水平的假设 可以作为其发展能力的有用预测指标。干扰素-T是 牛胚胎表达和分泌的1型干扰素 和绵羊在怀孕早期，虽然它们的确切生理作用 仍不清楚，有越来越多的证据表明这些干扰素在 妊娠识别的机制。干扰素-T可以很容易地在 体外衍生牛囊胚的培养液，但存在 几乎没有关于观察到的重要意义的信息 不同的胚泡产生的干扰素-T量差异很大。这个 因此，这项建议的目的是为了进一步了解干扰素-t。 胚胎的生产及其对后续研究的意义 发展。需要解决的具体问题是：1)能否培养 条件影响干扰素-t的产生；2)其基因型别是否有影响 产生；3)体外产生的干扰素-t的量 胚泡与体内产生的胚泡不同，什么是 在胚泡中发现的干扰素-t增加的性质 在胚泡形成时年龄较大；4)是否印记了干扰素-t或干扰素-t的量 由孤雌生殖和雄生殖囊胚产生的不同于 最后，对照胚胎的干扰素-T的量，即 在培养中分泌是预测怀孕可能性的有用辅助 在转给收件人之后。

DESCRIPTION (adapted from the applicant's Abstract): The goal of this study is to investigate the possibility of using marker-assisted selection of superior embryos to increase pregnancy rates following transfer of in vitro-derived blastocysts. Such a strategy could have a significant impact on the treatment of fertility problems in humans, where pregnancy rates after in vitro fertilization and transfer of early stage embryos have remained well below 25%. An investigation of the feasibility of marker-assisted embryo selection requires a large number of embryos and recipients under controlled conditions, criteria that are unlikely to be met for human embryos. It is, therefore, proposed to use the secretion of interferon-tau (IFN-t) by bovine blastocysts as a model system to examine the hypothesis that the level of a protein produced by an individual embryo can be a useful predictor of its developmental competence. The IFN-t are Type 1 interferons that are expressed and secreted by the embryos of cattle and sheep during early pregnancy and while their precise physiological role remains unclear, there is mounting evidence implicating these interferons in the mechanism of pregnancy recognition. IFN-t can be easily detected in the culture medium of in vitro-derived bovine blastocyst, but there exists virtually no information on the significance of the observation that individual blastocysts can produce vastly different amounts of IFN-t. The aims of this proposal, therefore, are to gain further understanding of IFN-t production in embryos as well as its significance for subsequent development. Specific questions to be addressed are: 1) can culture conditions affect IFN-t production; 2) are there genotypic effects on its production; 3) does the amount of IFN-t produced by in vitro-derived blastocysts differ from that of blastocysts generated in vivo, and what is the nature of the increase in interferon-t that is found in blastocysts that are older at blastulation; 4) is IFN-t imprinted or does the amount of IFN-t that is produced by parthenogenetic and androgenetic blastocysts differ from that of control embryos, and lastly, 5) can the amount of IFN-t that is secreted in culture be a useful aid to predict the likelihood of pregnancy following transfer into recipients.