Controlled release of multiple epidermal induction factors through core-shell nanofibers for skin regeneration

With advances in the field of tissue engineering, it is increasingly recognized that biodegradable and biocompatible scaffolds incorporated with multiple wound healing mediators might serve as the most promising medical devices for skin tissue regeneration. Through controlled drug delivery, these medical devices can reduce the toxicity effects and optimize clinical efficiency. In this study, we first encapsulated multiple epidermal induction factors (EIF) such as the epidermal growth factor (EGF), insulin, hydrocortisone, and retinoic acid (RA) with gelatin and poly(L-lactic acid)-co-poly-(ε-caprolactone) (PLLCL) solutions and performed electrospinning by two different approaches: blend spinning and core-shell spinning. No burst release was detected from EIF encapsulated core-shell nanofibers; however, an initial 44.9% burst release from EIF blended nanofibers was observed over a period of 15 days. The epidermal differentiation potential of adipose-derived stem cells (ADSCs) was evaluated for EIF-containing scaffolds prepared either by core-shell spinning or by blend spinning. After 15 days of cell culture, the proliferation of ADSCs on EIF encapsulated core-shell nanofibers was the highest. Moreover, a higher percentage of ADSCs got differentiated to epidermal lineages on EIF encapsulated core-shell nanofibers compared to the cell differentiation on EIF blended nanofibers, which can be attributed to the sustained release of EIF from the core-shell nanofibers. Our study demonstrated that the EIF encapsulated core-shell nanofibers might serve as a promising tissue engineered graft for skin regeneration.