Improvement of Mouse Preantral Follicle Survival and Development following Co-Culture with Ovarian Parenchyma Cell Suspension

The parallel and continued improvements in both infertility treatment and the management of malignancycases have brought to the forefront the potential for fertility preservation. Using ovarian follicular resourcescan effectively improve reproductive capacity and prevent infertility. The primary aim of this research was to try togenerate an appropriate in vivo environment for the growth of the mouse follicles. Hence, the possible effects of theovarian parenchyma cell suspension were explored on the growth and maturation of preantral follicles in vitro. In this experimental study, ovarian parenchymal cells were mechanically dissociated frompreantral follicles of 12-14 days-old NMRI mice and then divided into 5 experimental groups (G1: Control, G2: Freshfollicle with fresh parenchyma cell suspension, G3: Vitrified-warmed follicle with fresh parenchyma cell suspension,G4: Fresh follicle with frozen-thawed parenchyma cell suspension, and G5: Vitrified-warmed follicle with frozen-thawedparenchyma cell suspension). The diameter of the follicles and immature oocytes, viability, antrum formation,resumption of meiosis, in vitro fertilization (IVF), and Gdf9, Bmp6, and Bmp15 gene expression were examined ondifferent periods. The diameter of the follicles and the oocytes on days 4 and 8, as well as the survival rate of the follicles upto day 12, were significantly higher in G2 and G4 compared to the Ctrl group (G1: 73.66%, G2:87.99%, G3: 82.70%,G4: 94.37%, and G5: 78.59%). Expression of growth marker genes for G3, and G5 groups was significantly higherthan other groups, which indicated the protective effects of parenchyma cell suspension on follicles damaged by vitrificationsolutions. The growth, survival, and maturation of preantral follicles could be enhanced by co-culturing them withovarian parenchyma cells. Further studies are needed to optimize the conditions for a successful parenchyma cellsuspension-induced in vitro maturation (IVM) to occur in infertility clinics.