Application of Decellularized Porcine Sclera in Repairing Corneal Perforations and Lamellar Injuries

Scleras are mainly used for the treatment of glaucoma, eyelid damage, and scleral ulcers. Given that the sclera and cornea collectively constitute the complete external structure of the eyeball and both have the same tissue and cell origin, we attempted to identify scleral materials to treat lamellar and penetrating corneal injuries. Based on research in our center, antigenic components in decellularized porcine sclera (DPS) were removed using a simplified decellularization method, leaving the collagen structure and active components undamaged. DPS preserved the mechanical properties and did not significantly inhibit the proliferation and replication of human corneal epithelial cells. In vivo, the graft epithelium healed well after lamellar and penetrating scleral grafting, and the graft thickness did not change evidently. DPS can resist suture traction during scleral transplantation and maintain anterior chamber stability until day 28 post-operatively, especially in penetrating repairs. No obvious immune rejection of lamellar or penetrating scleral grafts was found 28 days after DPS transplantation. This study shows that DPS could be used as an alternative material for the emergency repair of corneal perforations and lamellar injuries, representing another application of sclera.

Acellularized Uvea Hydrogel as Novel Injectable Platform for Cell-Based Delivering Treatment of Retinal Degeneration and Optimizing Retinal Organoids Inducible System

Replenishing the retina with retinal pigment epithelial (RPE) cells derived from pluripotent stem cells (PSCs) has great promise for treating retinal degenerative diseases, but it is limited by poor cell survival and integration in vivo. Herein, porcine acellular sclera and uvea extracellular matrix (ECM) and their counterpart hydrogels are developed, and their effects on the biological behavior of human induced pluripotent stem cell (hiPSC)-derived RPE cells (hiPSC-RPE) and embryoid body (hiPSC-EB) differentiation are investigated. Both acellular ECM hydrogels have excellent biocompatibility and suitable biodegradability without evoking an obvious immune response. Most importantly, the decellularized uvea hydrogel-delivered cells' injection remarkably promotes the hiPSC-RPE cells' survival and integration in the subretinal space, rescues the photoreceptor cells' death and retinal gliosis, and restores vision in rats with retinal degeneration for a long duration. In addition, medium supplementation with decellularized uvea peptides promotes hiPSC-EBs onset morphogenesis and neural/retinal differentiation, forming layered retinal organoids. This study demonstrates that ECM hydrogel-delivered hiPSC-RPE cells' injection may be a useful approach for treating retinal degeneration disease, combined with an optimized retinal seeding cells' induction program, which has potential for clinical application.