Van Keuren Margaret L, Saunders Thomas L
Transgenics Animal Model Core, Division of Molecular Medicine and Genetics, University of Michigan Medical School, Ann Arbor, MI 48109, USA.
Transgenic Res. 2004 Aug;13(4):363-71. doi: 10.1023/b:trag.0000040040.82536.a5.
Research on genetically engineered mice provides insights into the etiology, therapy, and genetic basis of human diseases. An important variable that affects the results of mouse studies is the health status of the animals. Pathogen burdens may confound observations and obscure underlying mechanisms. Mouse resource centers frequently rederive infected mouse strains. We review our experience on the use of a well-established technique, embryo transfer to rederive infected mouse strains. The following mouse pathogens were eliminated by embryo transfer: Mouse Parvovirus, Mouse Hepatitis Virus, Mouse Rotavirus, Mouse Encephalomyelitis Virus, Mouse Adenovirus, Helicobacter species, endoparasites, and ectoparasites. We rederived transgenic mouse lines, gene-targeted mouse lines, and lines with spontaneous mutations. In the majority of strains, fertilized eggs for embryo transfer were obtained by mating superovulated egg donors with males of the desired genotype. A total of 309 embryo transfers were performed to rederive 96 mouse strains. The pregnancy rate was 76%; 1996 pups were born, of which 43% carried the desired genotype. We performed 44 additional embryo transfers to rederive 15 other strains. The pregnancy rate was lower (45%) and none of the 135 pups carried the desired genotype. Although we successfully eliminated the pathogens in all transfers, we were unable to obtain pups with the desired genotype in 15 of 111 mouse lines. Multiple factors affect the efficiency of rederivation by embryo transfer. They include the response to superovulation by embryo donors, the number and age of stud males, the yield of fertilized eggs, the number of embryo transfers, and genotyping.
对基因工程小鼠的研究为深入了解人类疾病的病因、治疗方法及遗传基础提供了线索。影响小鼠研究结果的一个重要变量是动物的健康状况。病原体负荷可能会混淆观察结果并掩盖潜在机制。小鼠资源中心经常对受感染的小鼠品系进行重新培育。我们回顾了我们在使用一种成熟技术——胚胎移植来重新培育受感染小鼠品系方面的经验。通过胚胎移植消除了以下小鼠病原体：小鼠细小病毒、小鼠肝炎病毒、小鼠轮状病毒、小鼠脑脊髓炎病毒、小鼠腺病毒、幽门螺杆菌属、体内寄生虫和体外寄生虫。我们重新培育了转基因小鼠品系、基因靶向小鼠品系以及具有自发突变的品系。在大多数品系中，用于胚胎移植的受精卵是通过使超排卵的供体雌鼠与具有所需基因型的雄鼠交配获得的。总共进行了309次胚胎移植以重新培育96个小鼠品系。妊娠率为76%；共出生1996只幼崽，其中43%携带所需基因型。我们又进行了44次胚胎移植以重新培育另外15个品系。妊娠率较低（45%），135只幼崽中没有一只携带所需基因型。尽管我们在所有移植中都成功消除了病原体，但在111个小鼠品系中的15个品系中，我们未能获得具有所需基因型的幼崽。多种因素会影响胚胎移植重新培育的效率。这些因素包括胚胎供体对超排卵的反应、种公鼠的数量和年龄、受精卵的产量、胚胎移植的次数以及基因分型。
