Patterned collagen films loaded with miR-133b@MBG-NH2 for potential applications in corneal stromal injury repair.

Corneal stromal injury is a common surgical disease. With the development of tissue engineering materials, many artificial corneal scaffolds have developed to replace allograft corneal transplantation and solve the problem of corneal donor shortage. However, few researchers have paid attention to corneal stromal wound healing. Herein, a nanocomposite of amino modified mesoporous bioactive glass (MBG-NH2) and microRNA-133b (miR-133b) was introduced into the patterned collagen films to achieve corneal stromal injury repair. MBG-NH2 nanoparticles as a nano delivery carrier could efficiently load miR-133b and achieve the slow release of miR-133b. The physicochemical properties of collagen films were characterized and found the microgrooved collagen films loaded with miR-133b@MBG-NH2 nanoparticles possessed similar swelling properties, optical clarity, and biodegradability to the natural cornea. In vitro cell experiments were also conducted and proved that the patterned collagen films with miR-133b@MBG-NH2 possessed good biocompatibility, and miR-133b@MBG-NH2 nanoparticles could be significantly uptake by rabbit corneal stromal cells (RCSCs) and have a significant impact on the orientation, proliferation, migration, and gene expression of RCSCs. More importantly, the patterned collagen films with miR-133b@MBG-NH2 could effectively promote the migration of RCSCs and accelerate wound healing process, and down-regulate the expression level of α-SMA, COL-I, and CTGF genes associated with myofibroblast differentiation of corneal stromal cells, which has a potential application prospect in the repair of corneal stromal injury.