In vitro and in vivo evaluation of the wound healing capability of electrospun gelatin/PLLCL nanofibers

Recent progress in tissue-engineered skin grafts has alleviated the demand for autologous split thickness skin grafts for treatment of large skin wounds. In this study, a series of cost-effective nanofibrous scaffolds aimed at full-thickness wound healing are fabricated by blending gelatin (Gel) with poly(l-lactic acid)-b-poly(ε-caprolactone) (PLLCL) and electrospun to obtain composite Gel/PLLCL nanofibers in four different weight ratios (w/w) of 80:20 [Gel/PLLCL(20)], 70:30 [Gel/PLLCL(30)], 60:40 [Gel/PLLCL(40)], and 50:50 [Gel/PLLCL(50)]. The mechanical properties of these nanofibrous scaffolds were evaluated in both dry and wet conditions, and the Gel/PLLCL(40) retained suitable tensile stress (1.16 ± 0.03 MPa) to be handled even in wet conditions. Moreover, the proliferations of fibroblast cells on Gel/PLLCL(40) were 15%, 7% and 10% higher compared to cell proliferations on Gel/PLLCL(20), Gel/PLLCL(30), and Gel/PLLCL(50), respectively. In vitro results confirmed Gel/PLLCL(40) as the optimized scaffold composition suitable for skin tissue engineering. The healing ability of this scaffold was studied in vivo using mouse models. The Gel/PLLCL(40) greatly accelerated wound closure and regeneration occurring in the first 10 days of implantation compared to the control group. In addition, newly regenerated epidermis was only found in the nanofibrous scaffolds-treated group, and it was comparable to the epidermis of normal skin.