DEVELOPMENT OF AN EMBRYO CRYOPRESERVATION PROGRAM IN LABORATORY ANIMALS

该计划的目标是促进NIH动物的管理 遗传资源(NIHAGR)的开发利用 用于基因冷藏库的胚胎配子收集和处理技术 材料和提高生殖潜力。NIHAGR保持着一个 一系列动物模型物种，在物种内部，有大量的 生物医学研究中使用的无价的基因类型。胚胎保存用途 冷冻介质中的一种低温保护剂，允许充分脱水 在冷冻过程中保护卵裂球。在变暖和稀释之后 在冷冻保护剂中，胚胎被培养以评估体外发育。 将胚胎移植到受体雌性体内的监视器 发展，因此生物能力。冷藏库胚胎是 在需要重新派生之前一直保持。实验室的主要工作重点 努力的是研究和优化小鼠的冷藏库技术， 兔子和老鼠。一项主要的研究发现是胚胎的可冻性 有明显的混杂和受基因影响。这样的回应一直是 对小鼠进行了基因分型检查，其中大部分表现为基因- 标准化胚胎冷冻程序的特定存活率。 辅助性项目调查了改善长期经济状况的比较方面 定期胚胎保存，特别强调冷冻保护剂和 加强胚胎冷冻、升温、稀释和移植的方法。 兔子的工作重点是收集程序和保存 使用新开发的玻璃化冷冻程序的胚胎。最初的尝试 也开始恢复老鼠胚胎。初步尝试也有 开始对精子进行冷冻保存。这些技术将特别 对于从个体或个体中挽救有限的遗传物质很重要 体内繁殖力差的基因类型。

The program objective is to facilitate the management of the NIH Animal Genetic Resource (NIHAGR) through development and utilization of embryolgamete collection and handling techniques for cryobanking genetic material and improving reproductive potential. The NIHAGR maintains an array of animal model species and, within species, a vast number of invaluable genotypes used in biomedical research. Embryo preservation uses a cryoprotectant in the freezing medium which allows sufficient dehydration to protect the blastomere during freezing. Following warming and dilution of the cryoprotectant, embryos are cultured to assess in vitro development. Transplantation of embryos into recipient females monitors in vivo development and thus biological competence. Cryobanked embryos are maintained until needed for rederivation. The primary focus of laboratory efforts is the study and optimization of cryobanking technology in mice, rabbits and rats. A major research finding is that embryo freezability is confounded and influenced markedly by genotype. Such responses have been examined in over 64 mouse genotypes, most of which display genotype- specific survival rates to standardized embryo freeze-warming procedures. Ancillary projects investigate the comparative aspects of improving long- term embryo storage with particular emphasis on cryoprotectants and enhancing methods for embryo freezing, warming, dilution and transfer. Efforts in the rabbit focus on collection procedures and preservation of embryos using a newly developed vitrification procedure. Initial attempts also have begun to recover rat embryos. Preliminary attempts also have been initiated to cryopreserve sperm. These techniques will be especially important for salvaging limited genetic material from individuals or genotypes with poor in vivo fertility.