Fabrication and characterization of elastin-crosslinked silk fibroin material for tissue engineering

Abstract

Silk fibroin (SF) is a fibrous protein containing crystalline ¢-sheets with biocompatible and biodegradable properties. However, cell response and elasticity of SF is not sufficient for cardiovascular applications. In order to improve this property, we used elastin (EL) with SF by cross-linking with genipin. EL shows smooth muscle cells (SMCs) contractile phenotype and prevents intimal hyperplasia. Genipin is a cross linker agent which reacts on amino groups of proteins. Because SF exposes basic amino acid only at the terminal region, we expected to promote cell response by elastin content and maintain the structure of the SF. Contact angle observation showed that the hydrophobic surface character increased with increasing EL ratio. Also underwater tension testing showed that EL adds flexibility to films. In addition, higher attachment and lower proliferation of SMCs was observed by increasing the EL ratio. This phenomenon suggests that elastin in the film promotes contractile phenotype of SMCs which results in suppressing cell proliferation.