Follicular renewal and stemness potency of follicular cells depended of telomerase activity and TERT expression – short review

Several hypotheses have been proposed, relating to the potential genesis of follicular cells in the ovarian niche. Reports using mice as an experimental model have suggested that the ovaries may contain stem cells that are likely involved in the formation of new follicles in adult reproductive life. Over recent years, various types of ovarian cells have been identified and described to confirm or disprove the existence of ovarian adult stem cells. Most research is focused on granulosa cells (GCs), which are essential for follicular development and maturation of female germ cells (oocytes). GCs exhibit the features of stem cells, such as expression of stem cell markers: OCT-4, Sox-2, Nanog as well as certain markers of mesenchymal stem cells, including CD29, CD44, CD90, CD105, CD117, and CD166. Another discovery in favor of the potential stemness of GCs is their ability to transdifferentiate towards other cell lines and high telomerase (TERT) activity in dividing compartments of the follicle during its maturation.