Theranostics 2020; 10(6):2538-2552. doi:10.7150/thno.39386 This issue Cite
Research Paper
1. Shanghai Key Laboratory of Orthopaedic Implants, Department of Orthopaedics, Ninth People's Hospital, School of Medicine, Shanghai Jiao Tong University, Shanghai 200011, China.
2. Department of Nuclear Medicine, Renji Hospital, School of Medicine, Shanghai Jiao Tong University, Shanghai 200127, China.
3. State Key Laboratory for Manufacturing System Engineering, School of Mechanical Engineering, Xi'an Jiao Tong University, Xi'an 710054, China.
4. School of Biomedical Engineering, Shanghai Jiao Tong University, Shanghai 200240, China.
5. Engineering Research Center of Digital Medicine, Ministry of Education, Shanghai 200030, China.
6. Center of Analysis and Test, Shanghai Jiao Tong University, Shanghai 200240, China.
7. Shanghai University of Medicine and Health sciences, Shanghai 201318, China.
8. Department of Bone and Joint Surgery, Renji Hospital, School of Medicine, Shanghai Jiao Tong University, Shanghai 200127, China.
9. Centre for Orthopaedic Research, School of Surgery, The University of Western Australia, Crawley 6009, Australia.
* These authors contributed equally to this work.
Purpose: One of the essential requirements in maintaining the normal joint motor function is the perfect tribological property of the articular cartilage. Many cartilage regeneration strategies have been developed for treatment in early stages of osteoarthritis, but there is little information on how repaired articular cartilage regains durability. The identification of biomarkers that can predict wear resistant property is critical to advancing the success of cartilage regeneration therapies. Proteoglycan 4 (PRG4) is a macromolecule distributing on the chondrocyte surface that contributes to lubrication. In this study, we investigate if PRG4 expression is associated with tribological properties of regenerated cartilage, and is able to predict its wear resistant status.
Methods: Two different strategies including bone marrow enrichment plus microfracture (B/BME-MFX) and microfracture alone (B-MFX) of cartilage repair in sheep were used. PRG4 expression and a series of tribological parameters on regenerated cartilage were rigorously examined and compared.
Results: Highly and continuously expression of PRG4 in regenerated cartilage surface was negatively correlated with each tribological parameter (P<0.0001, respectively). Multivariate analysis showed that PRG4 expression was the key predictor that contributed to the promotion of cartilage wear resistance.
Conclusion: Higher PRG4 expression in regenerated cartilage is significantly associated with wear resistance improvement. PRG4 may be useful for predicting the wear resistant status of regenerated cartilage and determining the optimal cartilage repair strategy.
Keywords: Proteoglycan 4, cartilage regeneration, biotribology, wear resistance, bone marrow enrichment.