Novel nanofibrous multicomponent scaffolds for bone tissue engineering

Abstract

Scaffold-based tissue engineering has been investigated widely for bone tissue regeneration in human bodies. Electrospinning is a versatile and popular technique for fabricating nanofibrous tissue engineering scaffolds which can be used for regenerating tissues such as skin, bone and peripheral nerve. However, normally constructed scaffolds are simple porous structures which merely provide a substrate for cells. Owing to the bioinertness of polymers for scaffolds and shortcomings of conventional electrospun scaffolds, most electrospun scaffolds cannot lead to successful regeneration of targeted tissues. Creating multifunctional nanofibrous scaffolds by using the multicomponent scaffold approach can be a successful strategy for regenerating tissues such as bone. To demonstrate this approach, assisted by emulsion electrospinning and composite fiber electrospinning, angiogenic (by VEGF), osteoconductive (by Ca-P nanoparticles) and osteoinductive (by BMP-2) tricomponent scaffolds for bone tissue regeneration were formed through multi-source dual-power electrospinning. The novel scaffolds consisted of rhVEGF/(PLGA/PEG) fibers, Ca-P/PLGA fibers and rhBMP-2/PLGA fibers which were evenly distributed in the scaffolds (Fig.1). Tricomponent scaffolds exhibited angiogenic property (Fig.2), which would facilitate vascularization, a critical issue in bone tissue engineering. In vitro biological investigations employing mesenchymal stem cells showed superior biological performance of tricomponent scaffolds over mono- or bicomponent scaffolds. Gene expressions were shown to be upregulated by tricomponent scaffolds (Fig.3).