Development of an optimal protocol for isolation and purification of human granulosa cells in patients with different ovarian reserves

The aim of the current study was to develop an accurate and reproducible method for isolation of granulosa cells (GCs) in patients with different ovarian reserves. The cells of healthy individuals and patients with polycystic ovary syndrome (PCOS) were isolated using a modified two-step Percoll density gradient centrifugation. The cells of patients with poor ovarian response (POR) were isolated using a one-step method suitable for samples containing few cells. Cells extracted using these purification techniques were compared regarding cell yield, viability and purity using immunocytochemistry, flow cytometry, Cell Counting Kit-8, western blotting and RNA integrity analysis. The purity and activity of the cells in the POR group were comparable with those in the healthy and PCOS groups and no statistically significant differences were identified. Furthermore, isolated cells analyzed for RNA integrity indicated good quality RNA and presented an RNA integrity number of 8-10, demonstrating that the technique enabled the isolation of GCs from different types of patients. Thus, a reliable and reproducible technique for the isolation of pure GCs with high yield is described in the present study. This protocol provides an efficient method targeted to patients with different ovarian reserve functions that enables the preparation of GCs for evaluating their molecular functions.