Characterization of extracellular matrix modified poly(¿-caprolactone) electrospun scaffolds with differing fiber orientations for corneal stroma regeneration

Abstract

Alternatives to donor cornea transplantation based on tissue engineering are desirable to overcome the current severe donor tissue shortage. Many natural polymers have good biological properties but poor mechanical properties and degradation resistance; while synthetic polymers have good mechanical properties but do not contain biochemical molecules normally found in the real tissue. In addition, both fiber orientation and composition play a key role in dictating cell behavior within a scaffold. In this study, the effect on corneal stromal cells of adding decellularized corneal extracellular matrix (ECM) to an electrospun polymer with differing fiber organizations was explored. Electrospun matrices were generated using polycaprolactone (PCL) and PCL combined with ECM and electrospun into random, radial and perpendicularly aligned fiber scaffolds. Human corneal stromal cells were seeded onto these scaffolds and the effect of composition and orientation on the cells phenotype was assessed. Incorporation of ECM into PCL increased hydrophilicity of scaffolds without an adverse effect on Young's modulus. Cells seeded on these matrices adopted different morphologies that followed the orientation of the fibers. Keratocyte markers were increased in all types of scaffolds compared to tissue culture plastic. Scaffolds with radial and perpendicularly aligned fibers promoted enhanced cell migration. Aligned scaffolds with incorporated ECM show promise for their use as cell-free implants that promote endogenous repopulation by neighboring cells.