title: Growth factor-eluting technologies for bone tissue engineering.
abstract: Growth factors are essential orchestrators of the normal bone fracture healing response. For non-union defects, delivery of exogenous growth factors to the injured site significantly improves healing outcomes. However, current clinical methods for scaffold-based growth factor delivery are fairly rudimentary, and there is a need for greater spatial and temporal regulation to increase their in vivo efficacy. Various approaches used to provide spatiotemporal control of growth factor delivery from bone tissue engineering scaffolds include physical entrapment, chemical binding, surface modifications, biomineralization, micro- and nanoparticle encapsulation, and genetically engineered cells. Here, we provide a brief review of these technologies, describing the fundamental mechanisms used to regulate release kinetics. Examples of their use in pre-clinical studies are discussed, and their capacities to provide tunable, growth factor delivery are compared. These advanced scaffold systems have the potential to provide safer, more effective therapies for bone regeneration than the systems currently employed in the clinic.
authors.affiliation: Department of Biomedical Engineering, Translational Tissue Engineering Center, Johns Hopkins University, 400 N. Broadway, Smith 5023, Baltimore, MD, 21231, USA.
authors.forename: Ethan
authors.initials: E
authors.lastname: Nyberg
authors.affiliation: Department of Neurosurgery, Johns Hopkins University School of Medicine, Baltimore, MD, USA.
authors.forename: Christina
authors.initials: C
authors.lastname: Holmes
authors.affiliation: Department of Neurosurgery, Johns Hopkins University School of Medicine, Baltimore, MD, USA.
authors.forename: Timothy
authors.initials: T
authors.lastname: Witham
authors.affiliation: Department of Biomedical Engineering, Translational Tissue Engineering Center, Johns Hopkins University, 400 N. Broadway, Smith 5023, Baltimore, MD, 21231, USA. wgrayson@jhmi.edu.|Department of Material Sciences & Engineering, Johns Hopkins University School of Engineering, Baltimore, MD, USA. wgrayson@jhmi.edu.
authors.forename: Warren L
authors.initials: WL
authors.lastname: Grayson
mesh_terms: D000818:Animals; D001672:Biocompatible Materials / Q000737:chemistry* / Q000494:pharmacology; D001861:Bone Regeneration / Q000187:drug effects; D016503:Drug Delivery Systems / Q000379:methods*; D006801:Humans; D036341:Intercellular Signaling Peptides and Proteins / Q000494:pharmacology*; D010012:Osteogenesis / Q000187:drug effects*; D023822:Tissue Engineering / Q000379:methods; D054457:Tissue Scaffolds
chemical_list: D001672:Biocompatible Materials; D036341:Intercellular Signaling Peptides and Proteins
keywords: Biomaterials; Bone scaffold; Osteogenesis; Stem cells; Tissue engineering