OVARIAN INFERTILITY, STEM CELLS AND OOGENSIS IN VITRO

• Main Authors: Irma Virant-Klun, Andrej Vogler, Jasna Šinkovec, Matjaž Hren, Kristina Gruden, Elvira Maličev, Helena Meden-Vrtovec
• Format: Article
• Language: English
• Published: Slovenian Medical Association 2018-02-01
• Series: Zdravniški Vestnik
• Subjects: embrionalnim podobne matične celice; jajčna celica; kultura in vitro; površinski epitel jajčnika; prezgodnja menopavza
• Online Access: http://vestnik.szd.si/index.php/ZdravVest/article/view/2737

Background: In different human adult tissues and organs embryonic-like stem cells have already been found. A question is whether they are present also in the adult human ovary. In this study we tried to find whether embryonic-like stem cells are present in the ovarian surface epithe- lium of women with premature ovarian failure, and whether these cells can differentiate into oocytes by in vitro culture. Methods: In 10 women with premature ovarian failure the ovarian surface epithelium was laparo- scopically scraped. We tried to immunomagnetically isolate embryonic-like stem cells from the suspension of scraped cells and to confirm their existence immunocytochemically by the expression of the markers c-kit and surface antigen SSEA-4, characteristic of pluripotent stem cells. In the lab, we tried to differentiate stem cells into oocytes in a cell culture medium with added heterologous follicular fluid from the in vitro fertilization programme, which is rich in substances, and important for oocyte growth and maturation. The differentiation of oocyte-like cells was screened. Oocyte-like cells were isolated from the cell culture and im- munocytochemically stained for oocyte-specific markers (c-kit, VASA, ZP2-zona pellucida). Oocyte-like cells were analyzed for the expression of oocyte-specific genes (Oct-4A, ZP3, c-kit, SCP-3) by single-cell PCR. Results: From the ovarian surface epithelium of all patients small yellow coloured cells with diam- eters of 2 to 4 μm and positive for markers of pluripotent stem cells were isolated. In the lab, these cells were cultured into oocyte-like cells with diameter ranging from 60 to 80 μm. Some of oocyte-like cells were positive for oocyte-specific markers and expressed the genes, characteristic of oocytes, including meiotic genes. Conclusions: In patients with premature ovarian failure it is possible to culture oocyte-like cells from ovarian surface epithelium stem cells. Intense research is needed to evaluate the quality of oocyte-like cells developed in vitro and to estimate their potential use for in vitro fertilization in the far future.