Decellularized corneal lenticule embedded compressed collagen: toward a suturable collagenous construct for limbal reconstruction

Abstract

Recently, compressed collagen has attracted much attention as a potential alternative for a limbal epithelial stem cell (LESC) carrier to treat limbal stem cell deficiency (LSCD), in that it can provide mechanically improved collagen fibrillar structures compared to conventional collagen hydrogel. However, its clinical efficacy as an LESC carrier has not yet been studied through in vivo transplantation due to limited mechanical strength that cannot withstand a force induced by surgical suturing and low resistance to enzymatic degradation. This study firstly presents a suturable LESC carrier based on compressed collagen in the form of a biocomposite. The biocomposite was achieved by integrating a decellularized corneal lenticule, which is a decellularized stromal tissue obtained from corneal refractive surgery, inside a compressed collagen to form a sandwich structure. A suture retention test verified that the biocomposite has a much higher suture retention strength (0.56 ± 0.12 N) compared to the compressed collagen (0.02 ± 0.01 N). The biocomposite also exhibited more than 3 times higher resistance to enzymatic degradation, indicating long-term stability after transplantation. In vitro cell culture results revealed that the biocomposite effectively supported the expansion and stratification of the LESCs with expressions of putative stem cell and differentiated corneal epithelial cell markers. Finally, the biocomposite verified its clinical efficacy by stably delivering the LESCs onto an eye of a rabbit model of LSCD and effectively reconstructing the ocular surface.