In Vitro Culture And Maturation Of Preantral Follicles From Postmortem Mouse Ovary

To clone the human early embryo, and then extract the stem cells by using somatic cell nuclear transfer (SCNT) technique (namely "therapeutic cloning") for the tissue regeneration and organ renovation, plays an important role in the treatment of some major diseases and the development of the new drugs. It is clear that the study and the final clinical applications require a large amount of human matured oocytes, however, it seems to be prominent obstacle due to the known difficulties in obtaining the oocytes from female donation. It has been reported that the nerve cells obtained from the postmortem human brain tissue can still restore their functions after recovery processes, which inspired us that it may be possible to extract the preantral follicles from postmortem human ovaries for in vitro culture and maturation based on the successful technique for in vitro maturation (IVM) of human immature oocytes. On the consideration of the above-mentioned problems, we firstly tried to carry out in vitro culture and maturation of preantral follicles from the postmortem mouse ovaries.We have tried out some in vitro culture and maturation methods as reported in the literature, and finally confirmed an easier and convenient cultivation method mainly using the agar three-dimension (3D) matrix. The results showed that the mechanical plus enzymatic digestion method could harvest plenty of healthy preantral follicles from the 18 days-old mice that were sacrificed and postmortem delay was 24 or 48 hours at the 0 degree temperature. After 7 days in vitro cultivation, the survival rates of the two groups were 63.6% and 53.3%, and the final maturation rates were 14.6% and 20%, respectively, with the symbol of the release of first polar body.These results suggested that during certain period after the death of mice, there is still the chance for us to obtain the immature preantral follicles, and that these follicles still possess the potency to develop into the matured oocytes after the in-vitro cultivation,, providing the important foundation for us to apply this technique to human.