Biomimetic delivery of signals for bone tissue engineering

TLDR

Bone tissue engineering seeks to repair bone defects using biomaterials and signaling cues, yet clinical translation is limited largely because of inadequate delivery systems for these signals. The authors aim to develop biomimetic drug delivery systems that emulate the native extracellular matrix’s release and presentation of signaling molecules. These systems are designed to control the spatial, temporal, and kinetic release of signals based on drug physicochemical properties and biological mechanisms, and the article reviews such strategies. The review highlights fundamental principles and recent design examples that demonstrate the promise of biomimetic delivery 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.