Development of a Basement Membrane Substitute Incorporated Into an Electrospun Scaffold for 3D Skin Tissue Engineering

Abstract

A major challenge in the production of 3D tissue engineered skin is the recreation of the basement membrane region to promote secure attachment and yet segregation of keratinocytes from the dermal substitute impregnated with fibroblasts. We have previously shown that simple electrospun scaffolds provide fibres on which the cells attach, proliferate, and self-sort into epithelium and dermis. In a development of this in this study tri-layered scaffolds were then electrospun from poly L-lactic acid and poly hydroxybutyrate-co-hydroxyvalerate. In these a central layer of the scaffolds comprising nano-porous/nano-fibrous poly hydroxybutyrate-co-hydroxyvalerate fibres was interwoven into the bulk micro-porous poly L-lactic acid microfibers to mimic the basement membrane. Keratinocytes and fibroblasts seeded onto these scaffolds and cultured for 2 weeks showed that neither cell type was able to cross the central nano-porous barrier (shown by SEM, and fluorescence monitoring with CellTracker ™ ) while the micro-fibrous poly L-lactic acid provided a scaffold on which keratinocytes could create an epithelium and fibroblasts could create a dermal substitute depositing collagen. Although cells did not penetrate this barrier the interaction of cells was still evident-essential for epithelial development.