Water-Stable Three-Dimensional Ultrafine Fibrous Scaffoldsfrom Keratin for Cartilage Tissue Engineering.

Intrinsically water-stable scaffoldscomposed of ultrafine keratin fibers oriented randomly and evenlyin three dimensions were electrospun for cartilage tissue engineering.Keratin has been recognized as a biomaterial that could substantiallysupport the growth and development of multiple cell lines. Besides,three-dimensional (3D) ultrafine fibrous structures were preferredin tissue engineering due to their structural similarity to nativeextracellular matrices in soft tissues. Recently, we have developeda nontraditional approach to developing 3D fibrous scaffolds fromalcohol-soluble corn protein, zein, and verified their structuraladvantages in tissue engineering. However, keratin with highly cross-linkedmolecular structures could not be readily dissolved in common solventsfor fiber spinning, which required the remarkable drawability of solution.So far, 3D fibrous scaffolds from pure keratin for biomedical applicationshave not been reported. In this research, the highly cross-linkedkeratin from chicken feathers was de-cross-linked and disentangledinto linear and aligned molecules with preserved molecular weights,forming highly stretchable spinning dope. The solution was readilyelectrospun into scaffolds with ultrafine keratin fibers orientedrandomly in three dimensions. Due to the highly cross-linked molecularstructures, keratin scaffolds showed intrinsic water stability. Adipose-derivedmesenchymal stem cells could penetrate much deeper, proliferate, andchondrogenically differentiate remarkably better on the 3D keratinscaffolds than on 2D PLA fibrous scaffolds, 3D soy protein fibrousscaffolds, or 3D commercial nonfibrous scaffolds. In summary, theelectrospun 3D ultrafine fibrous scaffolds from keratin could be promisingcandidates for cartilage tissue engineering. [ABSTRACT FROM AUTHOR]