Improvement of in situ Follicular Activation and Early Development in Cryopreserved Human Ovarian Cortical Tissue by Co-Culturing with Mesenchymal Stem Cells

Abstract

Follicular loss and tissue degeneration are great challenges in ovarian tissue culture systems. Mesenchymal stem cells (MSC) secrete a cocktail of growth factors and cytokines which supports adjacent cells and tissues. The aim of the current study was to investigate the impact of human bone marrow (hBM)-MSC, as co-culture cells, on human follicular development in ovarian cortical tissue (OCT) culture. For this purpose, warmed OCT fragments were co-cultured with hBM-MSC for 8 days and compared to monocultured OCT. During the culture period, ovarian follicle survival and development in the OCT were evaluated using histological observation, follicular developmental-related genes expression, and estradiol production. Furthermore, cell proliferation and apoptosis were assessed. The results showed that there were no significant differences in conserved ovarian follicles with a normal morphology between the two groups. However, the percentage of developing follicles, as well as follicular developmental gene expression, significantly increased in the co-culture group compared to the monoculture group. On the other hand, compared with the monoculture group, the co-culture group demonstrated a significant increase in cell proliferation, indicated by Ki67 gene expression, as well as a dramatic decrease in apoptotic cell percentage, revealed by TUNEL assay. These findings indicated that co-culturing of hBM-MSC with OCT could improve follicular activation and early follicular development in human ovarian tissue culture systems.