Isolation, in vitro culture and cryopreservation with vitrification of mouse preantral follicles - preliminary results

Background: In the last decade the in vitro culture of preantral ovarian follicles is being given more attention. Beyond improving fundamental knowledge, this area of research has practical potential. Because the ovary contains great amount of preantral follicles, in vitro culture could provide access to enormous numbers of oocytes that, if viable, could be matured and fertilized in vitro to produce embryos for offspring production. The application of such in vitro cultured (IVC) follicles has a great potential for preserve reproductive efficiency of high value domestic animals, regardless the age or reproductive timing. Furthermore, there is a possibility for females of endangered species to extend and preserve their fertility using IVC follicles. Culturing follicles in vitro is very promising in the field of human assisted reproduction, especially as a new fertility preservation strategy applied before anticancer treatment Objectives: To test different media; investigate the follicular growth and estradiol production. Moreover, effects of different protectants (cythocalasin B and retinol) during vitrification were examined. Matrerials and Methods: Follicles were isolated from ovaries of BDF1 female mice and cultured in vitro in two different media. During in vitro growth, diameter and estradiol production were examined. Following vitrification, live/dead cell rate was measured by image analysis. Results and Discussion: The ovulation rate was the highest in the case of the Ultra-MEM based medium. Follicular growth was continous and statistically significant during the whole culture period. The most suitable supplement during the vitrification process was the retinol.