Three dimensional in vitro culture of preantral follicles following slow-freezing and vitrification of mouse ovarian tissue.

Abstract To evaluate the effects slow-freezing and vitrification on three dimensional in vitro culture of preantral follicles, ovaries of 12–14 days old female NMRI mice were isolated and randomly assigned to fresh control, slow-freezing and vitrification groups. Slow-freezing was performed using programmable freezer. Vitrification was carried out in a medium consisting of ethylene glycol (EG) and dimethyl sulphoxide (Me 2 SO) by needle immersion method. middle sized preantral follicles were mechanically isolated and cultured for 12 days in 0.7% sodium alginate gel. The follicles development and quantitative expression of oocyte specific genes ( Bmp15 , Gdf9 , Fgf8 ) and the growth related genes ( Igf1 , Kit , Kit-l ) were assessed after 1, 8 and 12 days of culture. Both cryopreserved groups showed reduction of follicular survival rates compared to the control group on days 8 and 12 of culture (P  Bmp15 , Gdf9 , Fgf8 , Kit and Kit-l during 12 days of culture (P  Kit and Kit-l expression in slow-freezing group significantly reduced on day 8 of culture (p  Igf1 expression was lower in slow-freezing group on 1st day of culture than vitrification and control groups (P