Articular cartilage regeneration: The role of endogenous mesenchymal stem/progenitor cell recruitment and migration

Background: Trauma- or osteoarthritis-related cartilage damage resulted in functional decline of joints and heavy burden of public health. Recently, the reparative role of mesenchymal stem/progenitor cells (MSCs) in articular cartilage (AC) reconstruction is drawing more and more attention. Objective: To provide a review on (1) the locations and categories of joint-resident MSCs, (2) the regulation of chondrogenic capacities of MSCs, (3) the migratory approaches of MSCs to diseased AC and regulatory mechanisms. Methods: PubMed and Web of Science were searched for English-language articles related to MSC recruitment and migration for AC repair until June 2019. The presence of various MSCs in or around joints, the potential approaches to diseased AC and the regenerative capacities of MSCs were reviewed. Results: Various intra- and peri-articular MSCs, with inherent migratory potentials, are present in multiple stem cell niches in or around joints. The recruitment and migration of joint-resident MSCs play crucial roles in endogenous AC repair. Multiple recruiting signals, such as chemokines, growth factors, etc., emerge during the development of AC diseases and participate in the regulation of MSC mobilization. Motivated MSCs could migrate into cartilage lesions and then exert multiple reparative potentials, including extracellular matrix (ECM) reconstruction and microenvironment modulation. Conclusion: In general, AC repair based on endogenous MSC recruitment and migration is a feasible strategy, and a promising research field. Furthermore. endogenous AC repair mediated by native MSCs would provide new opportunities to efficient preventative or therapeutic options for AC diseases. (C) 2019 The Authors. Published by Elsevier Inc.