Biologically Triggered Delivery of EGF from Polymer Fiber Patches

Wound healing is modulated by complex spatial and temporal regulation of growth factors within a wound site. Regenerative medicine seeks to generate materials that can mimic this environment for the healing of chronic or traumatic wounds. Herein, we report a programmed release of epidermal growth factor (EGF) from coextruded polymer fiber patches, which is triggered by the natural biological cascade of wound healing. Genetically engineered EGF containing a matrix metalloproteinase (MMP) cleavage site was covalently conjugated to a nonwoven poly­(ε-caprolactone) (PCL) fiber mat fabricated by multilayered melt coextrusion. The genetically modified EGF showed rapid release in the presence of a biological trigger, MMP-9, while a control protein showed negligible release. The biologically responsive fiber mat dramatically enhanced proliferation and migration of human keratinocytes in the presence of MMP-9. This study describes the release of a critical wound-healing growth factor as triggered by the biology inherent in the healing process.