Search

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]

In this work, novel electrospun scaffolds with fibersorientedrandomly and evenly in three dimensions (3D) including in the thicknessdirection were developed based on the principle of electrostatic repulsion.This unique structure is different from most electrospun scaffoldswith fibers oriented mainly in one direction. The structure of novel3D scaffolds could more closely mimic the 3D randomly oriented fibrousarchitectures in many native extracellular matrices (ECMs). The cellculture results of this study indicated that, instead of becomingflattened cells when cultured in conventional electrospun scaffolds,the cells cultured on novel 3D scaffolds could develop into stereoscopictopographies, which highly simulated in vivo 3D cellular morphologiesand are believed to be of vital importance for cells to function anddifferentiate appropriately. Also, due to the randomly oriented fibrousstructure, improvement of nearly 5 times in cell proliferation couldbe observed when comparing our 3D scaffolds with 2D counterparts after7 days of cell culture, while most currently reported 3D scaffoldsonly showed 1.5- to 2.5-fold improvement for the similar comparison.One mechanism of this fabrication process has also been proposed andshowed that the rapid delivery of electrons on the fibers was thecrucial factor for formation of 3D architectures. [ABSTRACT FROM AUTHOR]