title: Water-stable three-dimensional ultrafine fibrous scaffolds from keratin for cartilage tissue engineering.
abstract: Intrinsically water-stable scaffolds composed of ultrafine keratin fibers oriented randomly and evenly in three dimensions were electrospun for cartilage tissue engineering. Keratin has been recognized as a biomaterial that could substantially support the growth and development of multiple cell lines. Besides, three-dimensional (3D) ultrafine fibrous structures were preferred in tissue engineering due to their structural similarity to native extracellular matrices in soft tissues. Recently, we have developed a nontraditional approach to developing 3D fibrous scaffolds from alcohol-soluble corn protein, zein, and verified their structural advantages in tissue engineering. However, keratin with highly cross-linked molecular structures could not be readily dissolved in common solvents for fiber spinning, which required the remarkable drawability of solution. So far, 3D fibrous scaffolds from pure keratin for biomedical applications have not been reported. In this research, the highly cross-linked keratin from chicken feathers was de-cross-linked and disentangled into linear and aligned molecules with preserved molecular weights, forming highly stretchable spinning dope. The solution was readily electrospun into scaffolds with ultrafine keratin fibers oriented randomly in three dimensions. Due to the highly cross-linked molecular structures, keratin scaffolds showed intrinsic water stability. Adipose-derived mesenchymal stem cells could penetrate much deeper, proliferate, and chondrogenically differentiate remarkably better on the 3D keratin scaffolds than on 2D PLA fibrous scaffolds, 3D soy protein fibrous scaffolds, or 3D commercial nonfibrous scaffolds. In summary, the electrospun 3D ultrafine fibrous scaffolds from keratin could be promising candidates for cartilage tissue engineering.
authors.affiliation: Department of Textiles, Merchandising and Fashion Design, 234, HECO Building, University of Nebraska-Lincoln , Lincoln, Nebraska 68583-0802, United States.
authors.forename: Helan
authors.initials: H
authors.lastname: Xu
authors.forename: Shaobo
authors.initials: S
authors.lastname: Cai
authors.forename: Lan
authors.initials: L
authors.lastname: Xu
authors.forename: Yiqi
authors.initials: Y
authors.lastname: Yang
mesh_terms: D000818:Animals; D001672:Biocompatible Materials / Q000009:adverse effects / Q000737:chemistry*; D002356:Cartilage; D006801:Humans; D007633:Keratins / Q000737:chemistry*; D059630:Mesenchymal Stem Cells / Q000166:cytology / Q000187:drug effects; D052638:Particulate Matter; D012828:Silicones; D012995:Solubility; D023822:Tissue Engineering / Q000379:methods*; D054457:Tissue Scaffolds / Q000009:adverse effects / Q000737:chemistry*; D014867:Water / Q000737:chemistry*
chemical_list: D001672:Biocompatible Materials; D052638:Particulate Matter; D012828:Silicones; D014867:Water; D007633:Keratins