Human Ovarian Theca-Derived Multipotent Stem Cells Have The Potential to Differentiate into Oocyte-Like Cells In Vitro

Dalman, Azam; Totonchi, Mehdi; Valojerdi, Mojtaba Rezazadeh

doi:10.22074/cellj.2019.5651

Human Ovarian Theca-Derived Multipotent Stem Cells Have The Potential to Differentiate into Oocyte-Like Cells In Vitro

Document Type : Original Article

Authors

¹ Department of Embryology, Reproductive Biomedicine Research Center, Royan Institute for Reproductive Biomedicine, ACECR, Tehran, Iran

² Department of Genetics, Reproductive Biomedicine Research Center, Royan Institute for Reproductive Biomedicine, ACECR, Tehran, Iran

³ Department of Embryology, Reproductive Biomedicine Research Center, Royan Institute for Reproductive Biomedicine, ACECR, Tehran, Iran;Department of Anatomy, Faculty of Medical Science, Tarbiat Modares University, Tehran

10.22074/cellj.2019.5651

Abstract

Objective
In this study, we have examined human theca stem cells (hTSCs) in vitro differentiation capacity into human oocyte like cells (hOLCs).
Materials and Methods
In this interventional experiment study, hTSCs were isolated from the theca layer of small antral follicles (3-5 mm in size). Isolated hTSCs were expanded and cultured in differentiation medium, containing 5% human follicular fluid, for 50 days. Gene expressions of PRDM1, PRDM14, VASA, DAZL, OCT4, ZP1, 2, 3 GDF9, SCP3 and DMC1 were evaluated by quantitative reverse transcription polymerase chain reaction (qRT-PCR) on days 0, 18, and 25 after monoculture as well as one week after co-culture with human granulosa cells (hGCs). In addition, GDF9, OCT4, DAZL, VASA, and ZP3 proteins were immune-localized in oocyte-like structures.
Results
After 16-18 days, the color of the medium became acidic. After 25 days, the cells started to differentiate into round-shaped cells (20-25 µm diameter). One week after co-culturing with hGCs, the size of the round cells increased 60 to70 µm and convert to hOLCs. However, these growing cells expressed some primordial germ cell (PGC)- and germ cell genes (PRDM1, PRDM14, VASA, DAZL, and OCT4) as well as oocyte specific genes (ZP1, 2, 3 and GDF9), and meiotic-specific markers (SCP3 and DMC1). In addition, GDF9, OCT4, DAZL, VASA, and ZP3 proteins were present in hOLCs.
Conclusion
To sum up, hTSCs have the ability to differentiate into hOLCs. This introduced model paved the way for further in vitro studies of the exact mechanisms behind germ cell formation and differentiation. However, the functionality of hOLCs needs further investigation.

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