Sol-gel immobilized ovarian follicles: collaboration between two different cell types in hormone production and secretion

The immobilization of mammalian cells within semipermeable matrices which allow retention of viability and functionality has recently attracted research interest. In this study, rat mature ovarian follicles were encapsulated in sol-gel silica matrices for the evaluation of in vitro steroid hormones production. Tetraethoxysilane (TEOS) and tetrakis(2-hydroxyethyl) orthosilicate (THEOS) were evaluated for cell viability, progesterone and estradiol secretion and cell structure conservation. Significant differences were observed between TEOS and THEOS, which allowed encapsulation of follicles for 9 days. Although encapsulated follicles showed lower viability and proliferation rates than control follicles, they were able to secrete estradiol to the same extent as control follicles. This study demonstrated an effective collaboration between two different mammalian cell types in hormone production and secretion when encapsulated in silica matrices. These results could lead to the development of ovarian cell-based hormone delivery systems for the treatment of the symptoms of menopause and the Turner syndrome minimizing adverse effects.