MSC exosomes mediate cartilage repair by enhancing proliferation, attenuating apoptosis and modulating immune reactivity
Abstract
Mesenchymal stem cell (MSC) exosome was previously shown to be effective in repairing critical size osteochondral defects in an immunocompetent rat model. Here we investigate the cellular processes modulated by MSC exosomes and the mechanism of action underlying the exosome-mediated responses in cartilage repair. We observed that exosome-mediated repair of osteochondral defects was characterised by increased cellular proliferation and infiltration, enhanced matrix synthesis and a regenerative immune phenotype. Using chondrocyte cultures, we could attribute the rapid cellular proliferation and infiltration during exosome-mediated cartilage repair to exosomal CD73-mediated adenosine activation of AKT and ERK signalling. Inhibitors of AKT or ERK phosphorylation suppressed exosome-mediated increase in cell proliferation and migration but not matrix synthesis. The role of exosomal CD73 was confirmed by the attenuation of AKT and ERK signalling by AMPCP, a CD73 inhibitor and theophylline, an adenosine receptor antagonist. Exosome-treated defects also displayed a regenerative immune phenotype characterised by a higher infiltration of CD163+ regenerative M2 macrophages over CD86+ M1 macrophages, with a concomitant reduction in pro-inflammatory synovial cytokines IL-1β and TNF-α. Together, these observations demonstrated that the efficient osteochondral regeneration by MSC exosomes was effected through a coordinated mobilisation of multiple cell types and activation of several cellular processes.
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Administration of MSC-derived exosomes is efficacious in promoting skeletal muscle regeneration, cartilage repair, bone fracture healing, and cutaneous wound healing.
“Administration of MSCs derived exosomes has been reported to be efficacious in promoting skeletal muscle regeneration [12], cartilage repair [13], and bone fracture healing [14], and cutaneous wound healing [15].”
From A tailored bioactive 3D porous poly(lactic-acid)-exosome scaffold with osteo-immunomodulatory and osteogenic differentiation properties (2022) · cites this paper as [13]
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- Authors
- Zhang, S., Chuah, S. J., Lai, R. C., Hui, J. H. P., Lim, S. K., & Toh, W. S.
- Affiliations
- National University of Singapore (SG)
- Agency for Science, Technology and Research (SG)
- Corresponding author
- Toh, Wei Seong
- Venue
- Biomaterials
- Publisher
- Elsevier BV
- Published
- 2018-02
- Volume
- 156
- Pages
- 16-27
- ISSN
- 0142-9612 (ISSN-L)
- OpenAlex
- W2768238755
- Cited by
- 919
- References
- 57
- Citations by year
- 2026: 70 · 2025: 100 · 2024: 129 · 2023: 110 · 2022: 156 · 2021: 146 · 2020: 118 · 2019: 62 · 2018: 27
- FWCI
- 49.47
- Type
- journal article
- Language
- en
- Open access
- closed
- Locations
- Biomaterials (publishedVersion)
- PubMed (publishedVersion)
- Funders
- National University Healthcare System
- National University of Singapore (R221000083112, R221000090112)
- National Medical Research Council Singapore (R221000080511)
- Topics
- Health Sciences › Medicine › Rheumatology › Osteoarthritis Treatment and Mechanisms
- Health Sciences › Medicine › Genetics › Mesenchymal stem cell research
- Life Sciences › Biochemistry, Genetics and Molecular Biology › Molecular Biology › Extracellular vesicles in disease
- Keywords
- mesenchymal stem cell-derived exosomes, cartilage repair, osteochondral defects, CD73, adenosine signaling, Akt signaling, ERK signaling, chondrocyte proliferation, macrophage polarization, M2 macrophages, synovial cytokines, IL-1β, TNF-α, extracellular vesicles
- MeSH terms
- Adenosine, Animals, Cartilage, Cell Movement, Cell Survival, Extracellular Matrix, Female, Humans, Macrophages, Models, Biological, Regeneration, 5'-Nucleotidase, Cytokines, Rats, Sprague-Dawley, Apoptosis, Inflammation Mediators, Chondrocytes, MAP Kinase Signaling System, Cell Proliferation, Proto-Oncogene Proteins c-akt, Exosomes, Mesenchymal Stem Cells
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