Unraveling macrophage contributions to bone repair
Open accessAbstract
Macrophages have reemerged to prominence with widened understanding of their pleiotropic contributions to many biologies and pathologies. This includes clear advances in revealing their importance in wound healing. Here we have focused on the current state of knowledge with respect to bone repair, which has received relatively little scientific attention compared with its soft-tissue counterparts. Our detailed characterization of resident tissue macrophages residing in bone-lining tissues (osteomacs), including their pro-anabolic function, exposed a more prominent role for these cells in bone biology than previously anticipated. Recent studies have confirmed the importance of macrophages in early inflammatory processes that establish the healing cascade after bone fracture. Emerging data support that macrophage influence extends into both anabolic and catabolic phases of repair, suggesting that these cells have prolonged and diverse functions during fracture healing. More research is needed to clarify macrophage phase-specific contributions, temporospatial subpopulation variance and macrophage specific-molecular mediators. There is also clear motivation for determining whether macrophage alterations underlie compromised fracture healing. Overall, there is strong justification to pursue strategies targeting macrophages and/or their products for improving normal bone healing and overcoming failed repair.
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Pro-inflammatory macrophages predominate the first stage of fracture healing while anti-inflammatory macrophages are abundantly detected in the later stage of bone regeneration.
“pro-inflammatory macrophages predominant the first stage of fracture healing while anti-inflammatory macrophages are abundantly detected in later stage of bone regeneration [46].”
From A tailored bioactive 3D porous poly(lactic-acid)-exosome scaffold with osteo-immunomodulatory and osteogenic differentiation properties (2022) · cites this paper as [46]
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- Authors
- Wu, A. C., Raggatt, L. J., Alexander, K. A., & Pettit, A. R.
- Affiliations
- Translational Research Institute (AU)
- QIMR Berghofer Medical Research Institute (AU)
- Venue
- BoneKEy Reports
- Publisher
- Portico
- Published
- 2013-06-26
- Volume
- 2
- Pages
- 373-373
- ISSN
- 2047-6396 (ISSN-L)
- PMC
- PMC4098570
- OpenAlex
- W2001094576
- Cited by
- 256
- References
- 64
- Citations by year
- 2026: 9 · 2025: 10 · 2024: 19 · 2023: 21 · 2022: 37 · 2021: 26 · 2020: 28 · 2019: 18 · 2018: 23 · 2017: 21 · 2016: 30 · 2015: 12 · 2014: 2
- FWCI
- 1.38
- Type
- journal article
- Language
- en
- Open access
- green
- www.ncbi.nlm.nih.gov
- Locations
- BoneKEy Reports (publishedVersion)
- Europe PMC (PubMed Central) (publishedVersion)
- PubMed Central (publishedVersion)
- PubMed (publishedVersion)
- Topics
- Life Sciences › Biochemistry, Genetics and Molecular Biology › Molecular Biology › Bone Metabolism and Diseases
- Health Sciences › Medicine › Epidemiology › Bone fractures and treatments
- Health Sciences › Medicine › Rehabilitation › Wound Healing and Treatments
- Keywords
- macrophages, bone regeneration, fracture healing, bone formation, bone catabolism, bone inflammation, macrophage heterogeneity, macrophage-targeted therapy, impaired fracture healing
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