用改进的细胞核移植方法构建重构胚

为了能够找出一种既容易操作，又不需要特殊设备的核移植方法，对以前的操作进行了改进。首先以预先吸有细胞核或细胞的注射针在固定于持卵针上的卵母细胞透明带上穿刺两个孔，然后一边缓慢地将注射针回拔至卵周隙中，一边逐渐增加持卵针中的负压，直至极体与目标核质被完整吸入持卵针中而完成去核，最后在不拔出注射针的情况下直接注射细胞核或完整细胞进而完成重构胚的构建。用此方法对200个卵母细胞进行注核和注细胞操作，平均完成一个重构胚的构建各自耗时约40s和30s，成功率分别为62.6%和86.0%。用核染料Hoechst 33342 对卵母细胞的去核效率进行验证，去核成功率达到73.3%。实验证明，用此方法可以在只有倒置显微镜和显微操作仪的条件下一次性快速完成去核和注核，大大提高了细胞核移植的效率和重构胚成活率；更重要的是该方法操作简单，新手可以很快掌握该技术，易于在实际工作中推广应用。

Reconstruction of Embryo Using an Improved Nuclear Transfer Method

Previous methods used for nuclear transplantation were further investigated to develop a method that was both easy to carryout and did not require any special apparatus, such as Piezoimpact or Spindle-View. Following the puncture of zona pellucida with two holes by injection pipette that contained donor nuclei or cells, the injection pipette was pulled back to the perivitelline space while the negative pressure was increased in the holding pipette until the polar body and karyoplasm were wiped off completely. Then a reconstructed embryo was completed by the direct injection of the donor nucleus or cell without pulling out the injection pipette. 200 oocytes were manipulated using this method and it cost about 40 seconds with nucleus injection and about 30 seconds with cell injection to complete a reconstructed embryo. The success rates were 62.6% and 86.0%, respectively, and enucleation rate was about 73.3% validated by Hoechst 33342. Using this method, the nucleus was completely eliminated and another was injected using the microscope and micromanipulator. Moreover, the efficiency of nuclear transplantation and survival rate of reconstructed embryos were greatly improved. Furthermore, it is very easy to manipulate and popularize in practice.