A Biomimetic Follicle-Based Design for Engineering Reproductive Technologies

In the field of assisted reproductive technologies, oocyte in vitro maturation (IVM) has emerged as a potential alternative to overcome the limitations associated with standard ovarian stimulation treatments. However, current IVM protocols lack standardization and yield oocytes of inferior quality compared to those matured in vivo. To address this issue, novel biomaterials like hydrogels offer distinct advantages in cell culture by providing a 3D cellular environment and facilitating easy adjustment and characterization of mechanical properties, such as hydrogel stiffness. Herein, a novel and reusable bilayer hydrogel system is presented that accurately mimics the mechanical properties of the microenvironment surrounding oocyte maturation. The system comprises an outer layer fabricated from either a 3D-printed synthetic polymer (2-vinyl-4,6-diamino-1,3,5-triazine, (VDT)) or a natural polymer (chitosan), along with an inner layer composed of alginate. By faithfully replicating the mechanical properties of native tissue within a 3D culture environment, this system significantly improves the quality and developmental capacity of oocytes, thus resulting in successful embryo development. Overall, this innovative system holds great potential for future medical research and applications in cell culture, thus representing a significant advancement in assisted reproductive technologies.