Gelatin and PLG-based Scaffolds Differentially Support Follicle Integrity and Oocyte Growth in a 3D printed Scaffold

Purpose

Life-saving cancer treatments can impair ovarian function, leaving many survivors, particularly children and adolescents, at risk of infertility, endocrine dysfunction, and premature menopause. Because transplantation of cryopreserved ovarian tissue is contraindicated in patients with ovarian malignancies, biomaterial-based strategies are needed to support isolated follicles within a bioprosthetic ovary.

Methods

We compared three 3D-printed scaffold materials for ovarian tissue engineering: ultra-fluffy poly(lactic-co-glycolic acid) (UF-PLG), gelatin, and gelatin-coated UF-PLG (UF-PLG-gel). Murine secondary follicles were cultured on each scaffold for 2, 4, or 6 days. Follicle adherence, structural integrity, stromal cell attachment, and oocyte growth were assessed by confocal microscopy. The effects of increased scaffold crosslinking on scaffold stiffness and follicle outcomes were also evaluated.

Results

Scaffold composition significantly influenced follicle behavior. Gelatin scaffolds promoted follicle retention and preserved follicular integrity, whereas UF-PLG scaffolds exhibited frequent follicle detachment and rupture. Oocytes cultured on UF-PLG-gel scaffolds achieved diameters associated with developmental competence. Increasing scaffold crosslinking altered scaffold stiffness but produced only modest effects on follicle morphology, attachment, and oocyte growth.

Conclusions

Scaffold composition is a major determinant of follicle behavior in vitro, and the biomaterial properties supporting follicle maintenance may differ from those promoting oocyte growth. Multi-material scaffold designs may therefore be required to better support the distinct requirements of follicle maintenance and maturation in future bioprosthetic ovaries.