Current advances for bone regeneration based on tissue engineering strategies

Abstract

Bone tissue engineering (BTE) is a rapidly developing strategy for repairing critical-sized bone defects to address the unmet need for bone augmentation and skeletal repair. Effective therapies for bone regeneration primarily require the coordinated combination of innovative scaffolds, seed cells, and biological factors. However, current techniques in bone tissue engineering have not yet reached valid translation into clinical applications because of several limitations, such as weaker osteogenic differentiation, inadequate vascularization of scaffolds, and inefficient growth factor delivery. Therefore, further standardized protocols and innovative measures are required to overcome these shortcomings and facilitate the clinical application of these techniques to enhance bone regeneration. Given the deficiency of comprehensive studies in the development in BTE, our review systematically introduces the new types of biomimetic and bifunctional scaffolds. We describe the cell sources, biology of seed cells, growth factors, vascular development, and the interactions of relevant molecules. Furthermore, we discuss the challenges and perspectives that may propel the direction of future clinical delivery in bone regeneration.

Keywords

bone tissue engineering / stem cell / bone scaffold / growth factor / bone regeneration

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Acknowledgements

This work was supported by the National Natural Science Foundation of China (Nos. 51673029, 81330043, and 81071499), Beijing Talent Fund (No. 2016000021223ZK34), and another fund (No. PXM2018_026275_000001).

Compliance with ethics guidelines

Rui Shi, Yuelong Huang, Chi Ma, Chengai Wu, and Wei Tian declare that they have no conflict of interest. This manuscript is a review article and does not involve a research protocol requiring approval by the relevant institutional review board or ethics committee.

RIGHTS & PERMISSIONS

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