Fabricated tropoelastin-silk yarns and woven textiles for diverse tissue engineering applications

Electrospun yarns offer substantial opportunities for the fabrication of elastic scaffolds for flexible tissue engineering applications. Currently available yarns are predominantly made of synthetic elastic materials. Thus scaffolds made from these yarns typically lack cell signaling cues. This can result in poor integration or even rejection on implantation, which drive demands for a new generation of yarns made from natural biologically compatible materials. Here, we present a new type of cell-attractive, highly twisted protein-based yarns made from blended tropoelastin and silk fibroin. These yarns combine physical and biological benefits by being rendered elastic and bioactive through the incorporation of tropoelastin and strengthened through the presence of silk fibroin. Remarkably, the process delivered multi-meter long yarns of tropoelastin-silk mixture that were conducive to fabrication of meshes on hand-made frames. The resulting hydrated meshes are elastic and cell interactive. Furthermore, subcutaneous implantation of the meshes in mice demonstrates their tolerance and persistence over 8 weeks. This combination of mechanical properties, biocompatibility and processability into diverse shapes and patterns underscores the value of these materials and platform technology for tissue engineering applications. Statement of Significance Synthetic yarns are used to fabricate textile materials for various applications such as surgical meshes for hernia repair and pelvic organ prolapse. However, synthetic materials lack the attractive biological and physical cues characteristic of extracellular matrix and there is a demand for materials that can minimize postoperative complications. To address this need, we made yarns from a combination of recombinant human tropoelastin and silk fibroin using a modified electrospinning approach that blended these proteins into functional yarns. Prior to this study, no protein-based yarns using tropoelastin were available for the fabrication of functional textile materials. Multimeter-long, uniform and highly twisted yarns based on these proteins were elastic and cell interactive and demonstrated processing to yield textile fabrics. By using these yarns to weave fabrics, we demonstrate that an elastic human matrix protein blend can deliver a versatile platform technology to make textiles that can be explored for efficacy in tissue repair. (C) 2019 Acta Materialia Inc. Published by Elsevier Ltd. All rights reserved.