Biomimetic delivery of signals for bone tissue engineering

Abstract

Bone tissue engineering is an exciting approach to directly repair bone defects or engineer bone tissue for transplantation. Biomaterials play a pivotal role in providing a template and extracellular environment to support regenerative cells and promote tissue regeneration. A variety of signaling cues have been identified to regulate cellular activity, tissue development, and the healing process. Numerous studies and trials have shown the promise of tissue engineering, but successful translations of bone tissue engineering research into clinical applications have been limited, due in part to a lack of optimal delivery systems for these signals. Biomedical engineers are therefore highly motivated to develop biomimetic drug delivery systems, which benefit from mimicking signaling molecule release or presentation by the native extracellular matrix during development or the natural healing process. Engineered biomimetic drug delivery systems aim to provide control over the location, timing, and release kinetics of the signal molecules according to the drug’s physiochemical properties and specific biological mechanisms. This article reviews biomimetic strategies in signaling delivery for bone tissue engineering, with a focus on delivery systems rather than specific molecules. Both fundamental considerations and specific design strategies are discussed with examples of recent research progress, demonstrating the significance and potential of biomimetic delivery systems for bone tissue engineering.

Biomechanics: Drug delivery systems in bone tissue engineering

Bone tissue engineering offers exciting possibilities for repairing bone defects or regenerating bone tissue for transplantation, and biomimetic drug delivery systems (DDSs) hold promise in providing an environment to support the tissue regeneration. Biomimetic DDSs mimic the release of signaling molecules during development or in the natural healing process, and a team headed by Peter Ma at the University of Michigan in the United States conducted a review of the biomimetic strategies that have been adopted for bone tissue engineering. Various DDSs have been developed that mimic the natural healing or development processes, and they provide controlled drug release. The authors conclude that integrating DDSs with bone implants or scaffolds (which stimulate the growth of bone cells on their surface) could lead to advanced tissue engineering therapy for repairing bone defects.

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Funding

DOD | U.S. Army Medical Research and Materiel Command (Medical Research and Materiel Command, U.S. Army Medical Department)(W81XWH-12-2-0008)

U.S. Department of Health & Human Services | NIH | National Institute of Dental and Craniofacial Research (NIDCR)(DE022327)

U.S. Department of Health & Human Services | NIH | National Center for Advancing Translational Sciences (NCATS)(TR001711)

U.S. Department of Health & Human Services | NIH | National Heart, Lung, and Blood Institute (NHLBI)(HL136231)