Isolation and characterization of the human ovarian cell population for transplantation into an artificial ovary

Abstract

To support survival and growth of follicles, the transplantable artificial ovary should mimic the original organ, offering a physical (3D matrix) and biological support (cells). In order to replicate the ovarian cell populations, the aim of this study is to assess the proportions of stromal and endothelial cells in the ovarian cortex. To this end, ovarian biopsies were obtained from six women (mean age: 49 years). The epithelial layer and medulla were carefully removed. The cortex was finely minced and enzymatically digested and the isolated cells were fixed. For cell characterization, immunostaining for CD31 (for endothelial cells) and inhibin-α (for granulosa cells) was performed. Positive cells in each staining were counted and the proportion of the different cell populations was estimated from the total number of isolated cells. Since there is no specific marker for ovarian stromal cells, we estimated the proportion of these cells by performing a vimentin immunostaining and subtracting the proportions of CD31-and inhibin-α-positive cells. Immunostaining showed that 84% of isolated cells were vimentin-positive. From this pool, 3% were endothelial cells and 1% granulosa cells. Consequently, the population of ovarian stromal cells was 80%. In conclusion, our findings show that stromal cells represent the larger population of cells in the human ovarian cortex. While this ensures follicle survival and development in a normal ovary, we believe that the low proportion of endothelial cells could have a negative impact on the angiogenesis in the artificial ovary after the first days of transplantation.

Artificial Ovary for Young Female Breast Cancer Patients

“…An ovarian cell can support angiogenesis, and signal transduction of the artificial ovary is fundamental for follicle proliferation and maturation ( 97 ). Ovarian cells can secrete factors that can regulate the transformation of primordial follicles into primary follicles and simulate the microenvironment for follicle growth and survival proliferation ( 98 ).…”

“…Additionally, the best source for ovarian cells comes from fresh medulla part in the ovary after cancer remission, and this strategy not only can reduce the risk of reintroducing the malignant to the body, but it also can avoid the damaging effect of cryopreservation to ovarian cells. Because ovarian cells are sensitive to cryopreservation, chemotherapy has less effect on ovarian cells ( 97 ). Another source for the ovarian cell is the stem cell.…”

Exogenous Melatonin Ameliorates the Negative Effect of Osmotic Stress in Human and Bovine Ovarian Stromal Cells

“…During cryopreservation, all cells are exposed to the toxic effect of CPAs and the detrimental effects of freezing and warming steps [ 47 ], but a quantifiable link between ideal CPA equilibration and low toxicity in ovarian tissue cryopreservation is challenging to establish since each cell type likely has different optimal requirements for cryopreservation [ 47 ]. The main population of ovarian cortex cells is categorized as stromal cells (more than 80%) [ 48 , 49 ]. These cells play key roles in ovarian function and follicle development.…”