Electrospun fiber constructs for vocal fold tissue engineering: Effects of alignment and elastomeric polypeptide coating

Abstract

Vocal fold lamina propria extracellular matrix (ECM) is highly aligned and when injured, becomes disorganized with loss of the tissue’s critical biomechanical properties. This study examines the effects of electrospun fiber scaffold architecture and elastin-like polypeptide (ELP4) coating on human vocal fold fibroblast (HVFF) behavior for applications toward tissue engineering the vocal fold lamina propria. Electrospun Tecoflex™ scaffolds were made with aligned and unaligned fibers, and were characterized using scanning electron microscopy and uniaxial tensile testing. ELP4 was successfully adsorbed onto the scaffolds; HVFFs were seeded and their viability, proliferation, morphology and gene expression were characterized. Aligned and unaligned scaffolds had initial elastic moduli of ∼14MPa, ∼5MPa and ∼0.3MPa, ∼0.6MPa in the preferred and cross-preferred directions, respectively. Scaffold topography had an effect on the orientation of the cells, with HVFFs seeded on aligned scaffolds having a significantly different (p<0.001) angle of orientation than HVFFs cultured on unaligned scaffolds. This same effect and significant difference (p<0.001) was seen on aligned and unaligned scaffolds coated with ELP4. Scaffold alignment and ELP4 coating impacted ECM gene expression. ELP4 coating, and aligned scaffolds upregulated elastin synthesis when tested on day 7 without a concomitant upregulation of collagen III synthesis. Collectively, results indicate that aligned electrospun scaffolds and ELP4 coating are promising candidates in the development of biodegradeable vocal fold lamina propria constructs.