EMERGE patch, a novel electrogenic engineered material to enhance healing of severe corneal wounds

Abstract

Severe corneal wounds with stromal damage, especially those inflicted in battlefield and terrorist attacks, remain a significant clinical challenge. Naturally occurring wound electric fields have been demonstrated to have powerful effects on the healing of corneal epithelial wounds. Here we developed a functional scaffolding material with electrogenic pharmaceutical agents to enhance the healing of stromal wounds, i.e. Engineered Materials that Create Environments for ReGeneration via Electric Field (EMERGE). We first used an excimer laser to produce rat cornea stromal wounds with precisely controlled size and depth and demonstrated that such wounds produced large endogenous wound electric currents. The application of electrogenic compounds significantly increased the wound electric currents and wound healing. We then optimized the EMERGE patches with controlled fibril density, orientation, topography, thickness, optical, and biomechanical properties. The EMERGE patch has the advantage of the way that it supports optimal growth and migration of corneal epithelial cells in vitro. A corneal pocket keratotomy was used to secure the EMERGE patch in deep stroma rabbit corneal wounds without sutures. Corneas were examined with OCT and histological studies for up to four weeks and in one animal up to one year. The EMERGE patch increased wound healing significantly over the non-implant and electrogenic treatment controls (P < 0.05). Optical clarity was significantly improved (P < 0.05), and corneal thickness, histology, and staining of corneal cells showed favorable effects when treated with the EMERGE patch. This novel material thus represents a functional scaffolding with electrogenic agents to enhance the healing of severe corneal wounds.

Keywords: Cornea; Electric field; Electrogenic collagen patch; Engineered materials; Stromal injuries; Wound healing.