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Niu Z, Zhou Y, Liang M, Su F, Guo Q, Jing J, Xie J, Zhang D, Liu X. Crosstalk between ALK3(BMPR1A) deficiency and autophagy signaling mitigates pathological bone loss in osteoporosis. Bone 2024; 182:117052. [PMID: 38408588 DOI: 10.1016/j.bone.2024.117052] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 10/06/2023] [Revised: 02/08/2024] [Accepted: 02/18/2024] [Indexed: 02/28/2024]
Abstract
Postmenopausal osteoporosis is recognized to be one of the major skeleton diseases strongly associated with impaired bone formation. Previous reports have indicated that the importance of bone morphogenetic protein (BMP) signaling of osteoblast lineage in bone development via classical Smad signaling, however, its critical role in osteoporosis is still not well understood. In the current study, we aim to investigate the pathological role of BMPR1A, a key receptor of BMPs, in osteoporosis and its underlying mechanism. We first found that knockdown of BMPR1A by using Col1a1-creER in osteoblasts mitigated early bone loss of osteoporosis in mice, yet along with late bone maturation defects by reducing mineral adherence rate and bone formation rate in vivo. At the cellular level, we then observed that BMPR1A deficiency promoted the proliferation of pre-osteoblasts under osteoporotic conditions but hindered their late-stage mineralization. We finally elucidated that BMPR1A deficiency compensatorily triggered mTOR-autophagy perturbation by a higher level in early osteoporotic pre-osteoblasts thus resulting in the enhancement of transient cell proliferation but impairment of final mineralization. Taken together, this study indicated the significance of BMPR1A-mTOR/autophagy axis, as a double-edged sword, in osteoporotic bone formation and provided new cues for therapeutic strategies in osteoporosis.
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Affiliation(s)
- Zhixing Niu
- State Key Laboratory of Oral Diseases, West China Hospital of Stomatology, Sichuan University, Chengdu, Sichuan, China
| | - Yumeng Zhou
- State Key Laboratory of Oral Diseases, West China Hospital of Stomatology, Sichuan University, Chengdu, Sichuan, China; Institute of Biomedical Engineering, West China School of Basic Medical Sciences & Forensic Medicine, Sichuan University, Sichuan, China
| | - Muchun Liang
- State Key Laboratory of Oral Diseases, West China Hospital of Stomatology, Sichuan University, Chengdu, Sichuan, China; Institute of Biomedical Engineering, West China School of Basic Medical Sciences & Forensic Medicine, Sichuan University, Sichuan, China
| | - Fuqiang Su
- State Key Laboratory of Oral Diseases, West China Hospital of Stomatology, Sichuan University, Chengdu, Sichuan, China; Institute of Biomedical Engineering, West China School of Basic Medical Sciences & Forensic Medicine, Sichuan University, Sichuan, China
| | - Qiang Guo
- State Key Laboratory of Oral Diseases, West China Hospital of Stomatology, Sichuan University, Chengdu, Sichuan, China
| | - Junjun Jing
- State Key Laboratory of Oral Diseases, West China Hospital of Stomatology, Sichuan University, Chengdu, Sichuan, China
| | - Jing Xie
- State Key Laboratory of Oral Diseases, West China Hospital of Stomatology, Sichuan University, Chengdu, Sichuan, China.
| | - Demao Zhang
- State Key Laboratory of Oral Diseases, West China Hospital of Stomatology, Sichuan University, Chengdu, Sichuan, China; Institute of Biomedical Engineering, West China School of Basic Medical Sciences & Forensic Medicine, Sichuan University, Sichuan, China.
| | - Xiaoheng Liu
- Institute of Biomedical Engineering, West China School of Basic Medical Sciences & Forensic Medicine, Sichuan University, Sichuan, China
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He L. Biomaterials for Regenerative Cranioplasty: Current State of Clinical Application and Future Challenges. J Funct Biomater 2024; 15:84. [PMID: 38667541 PMCID: PMC11050949 DOI: 10.3390/jfb15040084] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/10/2024] [Revised: 03/18/2024] [Accepted: 03/26/2024] [Indexed: 04/28/2024] Open
Abstract
Acquired cranial defects are a prevalent condition in neurosurgery and call for cranioplasty, where the missing or defective cranium is replaced by an implant. Nevertheless, the biomaterials in current clinical applications are hardly exempt from long-term safety and comfort concerns. An appealing solution is regenerative cranioplasty, where biomaterials with/without cells and bioactive molecules are applied to induce the regeneration of the cranium and ultimately repair the cranial defects. This review examines the current state of research, development, and translational application of regenerative cranioplasty biomaterials and discusses the efforts required in future research. The first section briefly introduced the regenerative capacity of the cranium, including the spontaneous bone regeneration bioactivities and the presence of pluripotent skeletal stem cells in the cranial suture. Then, three major types of biomaterials for regenerative cranioplasty, namely the calcium phosphate/titanium (CaP/Ti) composites, mineralised collagen, and 3D-printed polycaprolactone (PCL) composites, are reviewed for their composition, material properties, and findings from clinical trials. The third part discusses perspectives on future research and development of regenerative cranioplasty biomaterials, with a considerable portion based on issues identified in clinical trials. This review aims to facilitate the development of biomaterials that ultimately contribute to a safer and more effective healing of cranial defects.
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Affiliation(s)
- Lizhe He
- Key Laboratory of 3D Printing Process and Equipment of Zhejiang Province, School of Mechanical Engineering, Zhejiang University, Hangzhou 310028, China
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3
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Gao X, Murphy MM, Peyer JG, Ni Y, Yang M, Zhang Y, Guo J, Kara N, Embree C, Tasdogan A, Ubellacker JM, Crane GM, Fang S, Zhao Z, Shen B, Morrison SJ. Leptin receptor + cells promote bone marrow innervation and regeneration by synthesizing nerve growth factor. Nat Cell Biol 2023; 25:1746-1757. [PMID: 38012403 PMCID: PMC10709146 DOI: 10.1038/s41556-023-01284-9] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/25/2023] [Accepted: 10/09/2023] [Indexed: 11/29/2023]
Abstract
The bone marrow contains peripheral nerves that promote haematopoietic regeneration after irradiation or chemotherapy (myeloablation), but little is known about how this is regulated. Here we found that nerve growth factor (NGF) produced by leptin receptor-expressing (LepR+) stromal cells is required to maintain nerve fibres in adult bone marrow. In nerveless bone marrow, steady-state haematopoiesis was normal but haematopoietic and vascular regeneration were impaired after myeloablation. LepR+ cells, and the adipocytes they gave rise to, increased NGF production after myeloablation, promoting nerve sprouting in the bone marrow and haematopoietic and vascular regeneration. Nerves promoted regeneration by activating β2 and β3 adrenergic receptor signalling in LepR+ cells, and potentially in adipocytes, increasing their production of multiple haematopoietic and vascular regeneration growth factors. Peripheral nerves and LepR+ cells thus promote bone marrow regeneration through a reciprocal relationship in which LepR+ cells sustain nerves by synthesizing NGF and nerves increase regeneration by promoting the production of growth factors by LepR+ cells.
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Affiliation(s)
- Xiang Gao
- National Institute of Biological Sciences, Beijing, China
- Tsinghua Institute of Multidisciplinary Biomedical Research, Tsinghua University, Beijing, China
- Academy for Advanced Interdisciplinary Studies, Peking University, Beijing, China
| | - Malea M Murphy
- Children's Research Institute and the Department of Pediatrics, University of Texas Southwestern Medical Center, Dallas, TX, USA
- Integrated Microscopy and Imaging Laboratory, Texas A&M Health Science Center, Texas A&M University, College Station, TX, USA
| | - James G Peyer
- Children's Research Institute and the Department of Pediatrics, University of Texas Southwestern Medical Center, Dallas, TX, USA
- Cambrian Bio, Inc., New York, NY, USA
| | - Yuehan Ni
- National Institute of Biological Sciences, Beijing, China
- College of Life Sciences, Beijing Normal University, Beijing, China
| | - Min Yang
- National Institute of Biological Sciences, Beijing, China
- College of Life Sciences, Beijing Normal University, Beijing, China
| | - Yixuan Zhang
- National Institute of Biological Sciences, Beijing, China
| | - Jiaming Guo
- National Institute of Biological Sciences, Beijing, China
- Academy for Advanced Interdisciplinary Studies, Peking University, Beijing, China
| | - Nergis Kara
- Children's Research Institute and the Department of Pediatrics, University of Texas Southwestern Medical Center, Dallas, TX, USA
- Ensoma, Inc., Boston, MA, USA
| | - Claire Embree
- Children's Research Institute and the Department of Pediatrics, University of Texas Southwestern Medical Center, Dallas, TX, USA
| | - Alpaslan Tasdogan
- Children's Research Institute and the Department of Pediatrics, University of Texas Southwestern Medical Center, Dallas, TX, USA
- Department of Dermatology, University Hospital Essen and German Cancer Consortium, Essen, Germany
| | - Jessalyn M Ubellacker
- Children's Research Institute and the Department of Pediatrics, University of Texas Southwestern Medical Center, Dallas, TX, USA
- Department of Molecular Metabolism, Harvard T.H. Chan School of Public Health, Boston, MA, USA
| | - Genevieve M Crane
- Robert J. Tomsich Pathology and Laboratory Medicine Institute, Cleveland Clinic, Cleveland, OH, USA
| | - Shentong Fang
- School of Biopharmacy, China Pharmaceutical University, Nanjing, China
| | - Zhiyu Zhao
- Children's Research Institute and the Department of Pediatrics, University of Texas Southwestern Medical Center, Dallas, TX, USA
| | - Bo Shen
- National Institute of Biological Sciences, Beijing, China.
- Tsinghua Institute of Multidisciplinary Biomedical Research, Tsinghua University, Beijing, China.
- Children's Research Institute and the Department of Pediatrics, University of Texas Southwestern Medical Center, Dallas, TX, USA.
| | - Sean J Morrison
- Children's Research Institute and the Department of Pediatrics, University of Texas Southwestern Medical Center, Dallas, TX, USA.
- Howard Hughes Medical Institute, UT Southwestern Medical Center, Dallas, TX, USA.
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Tooze RS, Miller KA, Swagemakers SMA, Calpena E, McGowan SJ, Boute O, Collet C, Johnson D, Laffargue F, de Leeuw N, Morton JV, Noons P, Ockeloen CW, Phipps JM, Tan TY, Timberlake AT, Vanlerberghe C, Wall SA, Weber A, Wilson LC, Zackai EH, Mathijssen IMJ, Twigg SRF, Wilkie AOM. Pathogenic variants in the paired-related homeobox 1 gene (PRRX1) cause craniosynostosis with incomplete penetrance. Genet Med 2023; 25:100883. [PMID: 37154149 DOI: 10.1016/j.gim.2023.100883] [Citation(s) in RCA: 1] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/22/2022] [Revised: 04/30/2023] [Accepted: 04/30/2023] [Indexed: 05/10/2023] Open
Abstract
PURPOSE Studies have previously implicated PRRX1 in craniofacial development, including demonstration of murine Prrx1 expression in the preosteogenic cells of the cranial sutures. We investigated the role of heterozygous missense and loss-of-function (LoF) variants in PRRX1 associated with craniosynostosis. METHODS Trio-based genome, exome, or targeted sequencing were used to screen PRRX1 in patients with craniosynostosis; immunofluorescence analyses were used to assess nuclear localization of wild-type and mutant proteins. RESULTS Genome sequencing identified 2 of 9 sporadically affected individuals with syndromic/multisuture craniosynostosis, who were heterozygous for rare/undescribed variants in PRRX1. Exome or targeted sequencing of PRRX1 revealed a further 9 of 1449 patients with craniosynostosis harboring deletions or rare heterozygous variants within the homeodomain. By collaboration, 7 additional individuals (4 families) were identified with putatively pathogenic PRRX1 variants. Immunofluorescence analyses showed that missense variants within the PRRX1 homeodomain cause abnormal nuclear localization. Of patients with variants considered likely pathogenic, bicoronal or other multisuture synostosis was present in 11 of 17 cases (65%). Pathogenic variants were inherited from unaffected relatives in many instances, yielding a 12.5% penetrance estimate for craniosynostosis. CONCLUSION This work supports a key role for PRRX1 in cranial suture development and shows that haploinsufficiency of PRRX1 is a relatively frequent cause of craniosynostosis.
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Affiliation(s)
- Rebecca S Tooze
- Clinical Genetics Group, MRC Weatherall Institute of Molecular Medicine, University of Oxford, Oxford, United Kingdom
| | - Kerry A Miller
- Clinical Genetics Group, MRC Weatherall Institute of Molecular Medicine, University of Oxford, Oxford, United Kingdom
| | - Sigrid M A Swagemakers
- Department of Pathology & Clinical Bioinformatics, Erasmus University Medical Center Rotterdam, Rotterdam, The Netherlands
| | - Eduardo Calpena
- Clinical Genetics Group, MRC Weatherall Institute of Molecular Medicine, University of Oxford, Oxford, United Kingdom
| | - Simon J McGowan
- Centre for Computational Biology, MRC Weatherall Institute of Molecular Medicine, University of Oxford, Oxford, United Kingdom
| | - Odile Boute
- Univ. Lille, CHU Lille, ULR 7364 - RADEME - Maladies Rares du Développement Embryonnaire et du Métabolisme, Clinique de Génétique, Lille, France
| | - Corinne Collet
- Genetics Department, Robert Debré University Hospital, APHP, Paris, France
| | - David Johnson
- Craniofacial Unit, Oxford University Hospitals NHS Foundation Trust, Oxford, United Kingdom
| | - Fanny Laffargue
- Clinical Genetics Service and Reference Centre for Rare Developmental Abnormalities and Intellectual Disabilities, University Hospital of Clermont-Ferrand, Clermont-Ferrand, France
| | - Nicole de Leeuw
- Department of Human Genetics, Radboud University Medical Center, Nijmegen, The Netherlands
| | - Jenny V Morton
- West Midlands Regional Clinical Genetics Service and Birmingham Health Partners, Birmingham Women's and Children's Hospitals NHS Foundation Trust, Birmingham, United Kingdom
| | - Peter Noons
- Department of Craniofacial Surgery, Birmingham Children's Hospital NHS Foundation Trust, Birmingham, United Kingdom
| | - Charlotte W Ockeloen
- Department of Human Genetics, Radboud University Medical Center, Nijmegen, The Netherlands
| | - Julie M Phipps
- Clinical Genetics Group, MRC Weatherall Institute of Molecular Medicine, University of Oxford, Oxford, United Kingdom; Oxford Centre for Genomic Medicine, Oxford University Hospitals NHS Foundation Trust, Oxford, United Kingdom
| | - Tiong Yang Tan
- Victorian Clinical Genetics Services, Murdoch Children's Research Institute, Royal Children's Hospital, Melbourne, Australia; Department of Paediatrics, University of Melbourne, Melbourne, VIC, Australia
| | - Andrew T Timberlake
- Hansjörg Wyss Department of Plastic Surgery, NYU Langone Medical Center, New York, NY
| | - Clemence Vanlerberghe
- Univ. Lille, CHU Lille, ULR 7364 - RADEME - Maladies Rares du Développement Embryonnaire et du Métabolisme, Clinique de Génétique, Lille, France
| | - Steven A Wall
- Craniofacial Unit, Oxford University Hospitals NHS Foundation Trust, Oxford, United Kingdom
| | - Astrid Weber
- Liverpool Centre for Genomic Medicine, Liverpool Women's NHS Foundation Trust, Liverpool, United Kingdom
| | - Louise C Wilson
- North East Thames Regional Genetics Service, Great Ormond Street Hospital for Children NHS Foundation Trust, London, United Kingdom
| | - Elaine H Zackai
- Clinical Genetics Center, Division of Human Genetics, Children's Hospital of Philadelphia, Philadelphia, PA
| | - Irene M J Mathijssen
- Department of Plastic and Reconstructive Surgery and Hand Surgery, Erasmus Medical Centre, University Medical Centre Rotterdam, Rotterdam, The Netherlands
| | - Stephen R F Twigg
- Clinical Genetics Group, MRC Weatherall Institute of Molecular Medicine, University of Oxford, Oxford, United Kingdom.
| | - Andrew O M Wilkie
- Clinical Genetics Group, MRC Weatherall Institute of Molecular Medicine, University of Oxford, Oxford, United Kingdom
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Yang R, Cao D, Suo J, Zhang L, Mo C, Wang M, Niu N, Yue R, Zou W. Premature aging of skeletal stem/progenitor cells rather than osteoblasts causes bone loss with decreased mechanosensation. Bone Res 2023; 11:35. [PMID: 37407584 DOI: 10.1038/s41413-023-00269-6] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/20/2022] [Revised: 04/03/2023] [Accepted: 05/12/2023] [Indexed: 07/07/2023] Open
Abstract
A distinct population of skeletal stem/progenitor cells (SSPCs) has been identified that is indispensable for the maintenance and remodeling of the adult skeleton. However, the cell types that are responsible for age-related bone loss and the characteristic changes in these cells during aging remain to be determined. Here, we established models of premature aging by conditional depletion of Zmpste24 (Z24) in mice and found that Prx1-dependent Z24 deletion, but not Osx-dependent Z24 deletion, caused significant bone loss. However, Acan-associated Z24 depletion caused only trabecular bone loss. Single-cell RNA sequencing (scRNA-seq) revealed that two populations of SSPCs, one that differentiates into trabecular bone cells and another that differentiates into cortical bone cells, were significantly decreased in Prx1-Cre; Z24f/f mice. Both premature SSPC populations exhibited apoptotic signaling pathway activation and decreased mechanosensation. Physical exercise reversed the effects of Z24 depletion on cellular apoptosis, extracellular matrix expression and bone mass. This study identified two populations of SSPCs that are responsible for premature aging-related bone loss. The impairment of mechanosensation in Z24-deficient SSPCs provides new insight into how physical exercise can be used to prevent bone aging.
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Affiliation(s)
- Ruici Yang
- State Key Laboratory of Cell Biology, Shanghai Institute of Biochemistry and Cell Biology, Center for Excellence in Molecular Cell Science, Chinese Academy of Sciences, University of Chinese Academy of Sciences, Shanghai, 200031, China
- Shenzhen Institute of Synthetic Biology, Shenzhen Institute of Advanced Technology, Chinese Academy of Sciences, Shenzhen, 518055, China
| | - Dandan Cao
- Institute for Regenerative Medicine, Shanghai East Hospital, Shanghai Key Laboratory of Signaling and Disease Research, Frontier Science Center for Stem Cell Research, School of Life Sciences and Technology, Tongji University, Shanghai, 200092, China
| | - Jinlong Suo
- Institute of Microsurgery on Extremities, and Department of Orthopedic Surgery, Shanghai Sixth People's Hospital Affiliated to Shanghai Jiao Tong University School of Medicine, Shanghai, 200233, China
| | - Lingli Zhang
- State Key Laboratory of Cell Biology, Shanghai Institute of Biochemistry and Cell Biology, Center for Excellence in Molecular Cell Science, Chinese Academy of Sciences, University of Chinese Academy of Sciences, Shanghai, 200031, China
| | - Chunyang Mo
- Institute for Regenerative Medicine, Shanghai East Hospital, Shanghai Key Laboratory of Signaling and Disease Research, Frontier Science Center for Stem Cell Research, School of Life Sciences and Technology, Tongji University, Shanghai, 200092, China
| | - Miaomiao Wang
- State Key Laboratory of Cell Biology, Shanghai Institute of Biochemistry and Cell Biology, Center for Excellence in Molecular Cell Science, Chinese Academy of Sciences, University of Chinese Academy of Sciences, Shanghai, 200031, China
| | - Ningning Niu
- State Key Laboratory of Cell Biology, Shanghai Institute of Biochemistry and Cell Biology, Center for Excellence in Molecular Cell Science, Chinese Academy of Sciences, University of Chinese Academy of Sciences, Shanghai, 200031, China
| | - Rui Yue
- Institute for Regenerative Medicine, Shanghai East Hospital, Shanghai Key Laboratory of Signaling and Disease Research, Frontier Science Center for Stem Cell Research, School of Life Sciences and Technology, Tongji University, Shanghai, 200092, China.
| | - Weiguo Zou
- State Key Laboratory of Cell Biology, Shanghai Institute of Biochemistry and Cell Biology, Center for Excellence in Molecular Cell Science, Chinese Academy of Sciences, University of Chinese Academy of Sciences, Shanghai, 200031, China.
- Institute of Microsurgery on Extremities, and Department of Orthopedic Surgery, Shanghai Sixth People's Hospital Affiliated to Shanghai Jiao Tong University School of Medicine, Shanghai, 200233, China.
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6
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Shen F, Huang X, He G, Shi Y. The emerging studies on mesenchymal progenitors in the long bone. Cell Biosci 2023; 13:105. [PMID: 37301964 DOI: 10.1186/s13578-023-01039-x] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/29/2022] [Accepted: 05/01/2023] [Indexed: 06/12/2023] Open
Abstract
Mesenchymal progenitors (MPs) are considered to play vital roles in bone development, growth, bone turnover, and repair. In recent years, benefiting from advanced approaches such as single-cell sequence, lineage tracing, flow cytometry, and transplantation, multiple MPs are identified and characterized in several locations of bone, including perichondrium, growth plate, periosteum, endosteum, trabecular bone, and stromal compartment. However, although great discoveries about skeletal stem cells (SSCs) and progenitors are present, it is still largely obscure how the varied landscape of MPs from different residing sites diversely contribute to the further differentiation of osteoblasts, osteocytes, chondrocytes, and other stromal cells in their respective destiny sites during development and regeneration. Here we discuss recent findings on MPs' origin, differentiation, and maintenance during long bone development and homeostasis, providing clues and models of how the MPs contribute to bone development and repair.
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Affiliation(s)
- Fangyuan Shen
- State Key Laboratory of Oral Diseases & National Clinical Research Center for Oral Diseases, West China Hospital of Stomatology, Sichuan University, Chengdu, China
| | - Xiaobin Huang
- Department of Oral and Maxillofacial Surgery/Pharmacology, School of Dental Medicine, University of Pennsylvania, Philadelphia, PA, USA
| | - Guangxu He
- Department of Orthopedics, The Second Xiangya Hospital, Central South University, NO. 139 Middle Renmin Road, Changsha, Hunan, China.
| | - Yu Shi
- State Key Laboratory of Oral Diseases & National Clinical Research Center for Oral Diseases, West China Hospital of Stomatology, Sichuan University, Chengdu, China.
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7
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Kitase Y, Prideaux M. Targeting osteocytes vs osteoblasts. Bone 2023; 170:116724. [PMID: 36868508 PMCID: PMC10062476 DOI: 10.1016/j.bone.2023.116724] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 10/17/2022] [Revised: 02/25/2023] [Accepted: 02/27/2023] [Indexed: 03/05/2023]
Abstract
Although osteoblasts and osteocytes are descended from the same lineage, they each have unique and essential roles in bone. Targeting gene deletion to osteoblasts and osteocytes using the Cre/loxP system has greatly increased our current understanding of how these cells function. Additionally, the use of the Cre/loxP system in conjunction with cell-specific reporters has enabled lineage tracing of these bone cells both in vivo and ex vivo. However, concerns have been raised regarding the specificity of the promoters used and the resulting off-target effects on cells within and outside of the bone. In this review, we have summarized the main mouse models that have been used to determine the functions of specific genes in osteoblasts and osteocytes. We discuss the expression patterns and specificity of the different promoter fragments during osteoblast to osteocyte differentiation in vivo. We also highlight how their expression in non-skeletal tissues may complicate the interpretation of study results. A thorough understanding of when and where these promoters are activated will enable improved study design and greater confidence in data interpretation.
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Affiliation(s)
- Y Kitase
- Indiana Center for Musculoskeletal Health, Department of Anatomy, Cell Biology and Physiology, School of Medicine, Indiana University, Indianapolis, IN 46202, United States of America
| | - M Prideaux
- Indiana Center for Musculoskeletal Health, Department of Anatomy, Cell Biology and Physiology, School of Medicine, Indiana University, Indianapolis, IN 46202, United States of America.
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8
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Cunningham CJ, Choi RB, Bullock WA, Robling AG. Perspective: The current state of Cre driver mouse lines in skeletal research: Challenges and opportunities. Bone 2023; 170:116719. [PMID: 36868507 PMCID: PMC10087282 DOI: 10.1016/j.bone.2023.116719] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 12/28/2022] [Revised: 02/15/2023] [Accepted: 02/19/2023] [Indexed: 03/04/2023]
Abstract
The Cre/Lox system has revolutionized the ability of biomedical researchers to ask very specific questions about the function of individual genes in specific cell types at specific times during development and/or disease progression in a variety of animal models. This is true in the skeletal biology field, and numerous Cre driver lines have been created to foster conditional gene manipulation in specific subpopulations of bone cells. However, as our ability to scrutinize these models increases, an increasing number of issues have been identified with most driver lines. All existing skeletal Cre mouse models exhibit problems in one or more of the following three areas: (1) cell type specificity-avoiding Cre expression in unintended cell types; (2) Cre inducibility-improving the dynamic range for Cre in inducible models (negligible Cre activity before induction and high Cre activity after induction); and (3) Cre toxicity-reducing the unwanted biological effects of Cre (beyond loxP recombination) on cellular processes and tissue health. These issues are hampering progress in understanding the biology of skeletal disease and aging, and consequently, identification of reliable therapeutic opportunities. Skeletal Cre models have not advanced technologically in decades despite the availability of improved tools, including multi-promoter-driven expression of permissive or fragmented recombinases, new dimerization systems, and alternative forms of recombinases and DNA sequence targets. We review the current state of skeletal Cre driver lines, and highlight some of the successes, failures, and opportunities to improve fidelity in the skeleton, based on successes pioneered in other areas of biomedical science.
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Affiliation(s)
- Connor J Cunningham
- Department of Anatomy, Cell Biology & Physiology, Indiana University School of Medicine, Indianapolis, IN, USA
| | - Roy B Choi
- Department of Anatomy, Cell Biology & Physiology, Indiana University School of Medicine, Indianapolis, IN, USA
| | | | - Alexander G Robling
- Department of Anatomy, Cell Biology & Physiology, Indiana University School of Medicine, Indianapolis, IN, USA; Richard L. Roudebush Veterans Affairs Medical Center, Indianapolis, IN, USA; Department of Biomedical Engineering, Indiana University-Purdue University at Indianapolis, Indianapolis, IN, USA; Indiana Center for Musculoskeletal Health, Indianapolis, IN, USA.
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9
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Rong L, Zhang L, Yang Z, Xu L. New insights into the properties, functions, and aging of skeletal stem cells. Osteoporos Int 2023:10.1007/s00198-023-06736-4. [PMID: 37069243 DOI: 10.1007/s00198-023-06736-4] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 09/24/2022] [Accepted: 03/27/2023] [Indexed: 04/19/2023]
Abstract
Bone-related diseases pose a major health burden for modern society. Bone is one of the organs that rely on stem cell function to maintain tissue homeostasis. Stem cell therapy has emerged as an effective new strategy to repair and replace damaged tissue. Although research on bone marrow mesenchymal stem cells has been conducted over the last few decades, the identity and definition of the true skeletal stem cell population remains controversial. Due to technological advances, some progress has been made in the prospective separation and function research of purified skeletal stem cells. Here, we reviewed the recent progress of highly purified skeletal stem cells, their function in bone development and repair, and the impact of aging on skeletal stem cells. Various studies on animal and human models distinguished and isolated skeletal stem cells using different surface markers based on flow-cytometry-activated cell sorting. The roles of different types of skeletal stem cells in bone growth, remodeling, and repair are gradually becoming clear. Thanks to technological advances, SSCs can be specifically identified and purified for functional testing and molecular analysis. The basic features of SSCs and their roles in bone development and repair and the effects of aging on SSCs are gradually being elucidated. Future mechanistic studies can help to develop new therapeutic interventions to improve various types of skeletal diseases and enhance the regenerative potential of SSCs.
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Affiliation(s)
- Lingjun Rong
- Department of Geriatric Endocrinology, The First Affiliated Hospital of Zhengzhou University, Zhengzhou, China
| | - Lixia Zhang
- Department of Endocrinology, The First Affiliated Hospital of Zhengzhou University, Zhengzhou, China
| | - Zaigang Yang
- Department of Geriatric Endocrinology, The First Affiliated Hospital of Zhengzhou University, Zhengzhou, China.
| | - Lijun Xu
- Department of Endocrinology, The First Affiliated Hospital of Zhengzhou University, Zhengzhou, China.
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10
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Huang Z, Su X, Julaiti M, Chen X, Luan Q. The role of PRX1-expressing cells in periodontal regeneration and wound healing. Front Physiol 2023; 14:978640. [PMID: 36960156 PMCID: PMC10027693 DOI: 10.3389/fphys.2023.978640] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/26/2022] [Accepted: 02/23/2023] [Indexed: 03/09/2023] Open
Abstract
The ideal outcome of wound healing is the complete restoration of the structure and function of the original tissue. Stem cells are one of the key factors in this process. Currently, the strategy of periodontal regeneration based on mesenchymal stem cells (MSCs) is generally used to expand stem cells in vitro and then transplant them in vivo. However, their clinical application is limited. In fact, the human body has the capacity to regenerate through stem cells residing in different tissues, even without external therapeutic intervention. Stem cell niches are present in many adult tissues, such as the periodontal ligament and gingiva, and stem cells might remain in a quiescent state in their niches until they are activated in response to a regenerative need. Activated stem cells can exit the niche and proliferate, self-renew, and differentiate to regenerate original structures. Thus, harnessing the regenerative potential of endogenous stem cells in situ has gained increasing attention as a simpler, safer, and more applicable alternative to stem cell transplantation. Nevertheless, there are several key problems to be solved in the application of periodontal mesenchymal stem cells. Thus, animal studies will be especially important to deepen our knowledge of the in vivo mechanisms of mesenchymal stem cells. Studies with conditional knockout mice, in which the expression of different proteins can be eliminated in a tissue-specific manner, are especially important. Post-natal cells expressing the paired-related homeobox protein 1 (PRX1 or PRRX1), a transcription factor expressed in the mesenchyme during craniofacial and limb development, have been shown to have characteristics of skeletal stem cells. Additionally, following wounding, dermal Prx1+ cells are found out of their dermal niches and contribute to subcutaneous tissue repair. Postnatal Prx1+ cells are uniquely injury-responsive. Meanwhile, current evidence shows that Prx1+ cells contribute to promote dentin formation, wound healing of alveolar bone and formation of mouse molar and periodontal ligament. Initial result of our research group also indicates Prx1-expressing cells in bone tissue around the punch wound area of gingiva increased gradually. Collectively, this review supports the future use of PRX1 cells to stimulate their potential to play an important role in endogenous regeneration during periodontal therapy.
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Affiliation(s)
- Zhen Huang
- Beijing Key Laboratory of Digital Stomatology, NMPA Key Laboratory for Dental Materials, Department of Periodontology, National Center for Stomatology, National Clinical Research Center for Oral Diseases, National Engineering Research Center of Oral Biomaterials and Digital Medical Devices, Research Center of Engineering and Technology for Computerized Dentistry Ministry of Health, Peking University School and Hospital of Stomatology, Beijing, China
| | - Xu Su
- Department of Stomatology, People’s Hospital of Xinjiang Uygur Autonomous Region, Urumqi, China
| | - Miliya Julaiti
- Department of Stomatology, People’s Hospital of Xinjiang Uygur Autonomous Region, Urumqi, China
| | - Xiaotao Chen
- Department of Stomatology, People’s Hospital of Xinjiang Uygur Autonomous Region, Urumqi, China
- *Correspondence: Xiaotao Chen, ; Qingxian Luan,
| | - Qingxian Luan
- Beijing Key Laboratory of Digital Stomatology, NMPA Key Laboratory for Dental Materials, Department of Periodontology, National Center for Stomatology, National Clinical Research Center for Oral Diseases, National Engineering Research Center of Oral Biomaterials and Digital Medical Devices, Research Center of Engineering and Technology for Computerized Dentistry Ministry of Health, Peking University School and Hospital of Stomatology, Beijing, China
- *Correspondence: Xiaotao Chen, ; Qingxian Luan,
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11
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Ko KI, DerGarabedian BP, Chen Z, Debnath R, Ko A, Link BN, Korostoff JM, Graves DT. Distinct fibroblast progenitor subpopulation expedites regenerative mucosal healing by immunomodulation. J Exp Med 2022; 220:213787. [PMID: 36584405 PMCID: PMC9827523 DOI: 10.1084/jem.20221350] [Citation(s) in RCA: 7] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/06/2022] [Revised: 11/10/2022] [Accepted: 12/19/2022] [Indexed: 12/31/2022] Open
Abstract
Injuries that heal by fibrosis can compromise organ function and increase patient morbidity. The oral mucosal barrier has a high regenerative capacity with minimal scarring, but the cellular mechanisms remain elusive. Here, we identify distinct postnatal paired-related homeobox-1+ (Prx1+) cells as a critical fibroblast subpopulation that expedites mucosal healing by facilitating early immune response. Using transplantation and genetic ablation model in mice, we show that oral mucosa enriched with Prx1+ cells heals faster than those that lack Prx1+ cells. Lineage tracing and scRNA-seq reveal that Prx1+ fibroblasts exhibit progenitor signatures in physiologic and injured conditions. Mechanistically, Prx1+ progenitors accelerate wound healing by differentiating into immunomodulatory SCA1+ fibroblasts, which prime macrophage recruitment through CCL2 as a key part of pro-wound healing response. Furthermore, human Prx1+ fibroblasts share similar gene and spatial profiles compared to their murine counterpart. Thus, our data suggest that Prx1+ fibroblasts may provide a valuable source in regenerative procedures for the treatment of corneal wounds and enteropathic fibrosis.
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Affiliation(s)
- Kang I. Ko
- Department of Periodontics, School of Dental Medicine, University of Pennsylvania, Philadelphia, PA, USA,Center for Innovation and Precision Dentistry, School of Dental Medicine, University of Pennsylvania, Philadelphia, PA, USA,Correspondence to Kang I. Ko:
| | - Brett P. DerGarabedian
- Department of Periodontics, School of Dental Medicine, University of Pennsylvania, Philadelphia, PA, USA
| | - Zhaoxu Chen
- Department of Periodontics, School of Dental Medicine, University of Pennsylvania, Philadelphia, PA, USA
| | - Rahul Debnath
- Department of Periodontics, School of Dental Medicine, University of Pennsylvania, Philadelphia, PA, USA
| | - Annette Ko
- Department of Periodontics, School of Dental Medicine, University of Pennsylvania, Philadelphia, PA, USA
| | - Brittany N. Link
- Department of Periodontics, School of Dental Medicine, University of Pennsylvania, Philadelphia, PA, USA
| | - Jonathan M. Korostoff
- Department of Periodontics, School of Dental Medicine, University of Pennsylvania, Philadelphia, PA, USA
| | - Dana T. Graves
- Department of Periodontics, School of Dental Medicine, University of Pennsylvania, Philadelphia, PA, USA
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12
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Yuan G, Li Z, Lin X, Li N, Xu R. New perspective of skeletal stem cells. BIOMATERIALS TRANSLATIONAL 2022; 3:280-294. [PMID: 36846511 PMCID: PMC9947737 DOI: 10.12336/biomatertransl.2022.04.007] [Citation(s) in RCA: 2] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 11/09/2022] [Revised: 11/29/2022] [Accepted: 12/19/2022] [Indexed: 03/01/2023]
Abstract
Tissue-resident stem cells are a group of stem cells distinguished by their capacity for self-renewal and multilineage differentiation capability with tissue specificity. Among these tissue-resident stem cells, skeletal stem cells (SSCs) were discovered in the growth plate region through a combination of cell surface markers and lineage tracing series. With the process of unravelling the anatomical variation of SSCs, researchers were also keen to investigate the developmental diversity outside the long bones, including in the sutures, craniofacial sites, and spinal regions. Recently, fluorescence-activated cell sorting, lineage tracing, and single-cell sequencing have been used to map lineage trajectories by studying SSCs with different spatiotemporal distributions. The SSC niche also plays a pivotal role in regulating SSC fate, such as cell-cell interactions mediated by multiple signalling pathways. This review focuses on discussing the spatial and temporal distribution of SSCs, and broadening our understanding of the diversity and plasticity of SSCs by summarizing the progress of research into SSCs in recent years.
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Affiliation(s)
- Guixin Yuan
- The First Affiliated Hospital of Xiamen University-ICMRS Collaborating Centre for Skeletal Stem Cell, State Key Laboratory of Cellular Stress Biology, Faculty of Medicine and Life Sciences, Xiamen University, Xiamen, Fujian Province, China,Xiamen Key Laboratory of Regeneration Medicine, Fujian Provincial Key Laboratory of Organ and Tissue Regeneration, School of Medicine, School of Medicine, Xiamen University, Xiamen, Fujian Province, China,Department of Human Anatomy, School of Medicine, Xiamen University, Xiamen, Fujian Province, China
| | - Zan Li
- Department of Sports Medicine & Research Centre of Sports Medicine, Xiangya Hospital, Central South University, Changsha, Hunan Province, China
| | - Xixi Lin
- The First Affiliated Hospital of Xiamen University-ICMRS Collaborating Centre for Skeletal Stem Cell, State Key Laboratory of Cellular Stress Biology, Faculty of Medicine and Life Sciences, Xiamen University, Xiamen, Fujian Province, China,Xiamen Key Laboratory of Regeneration Medicine, Fujian Provincial Key Laboratory of Organ and Tissue Regeneration, School of Medicine, School of Medicine, Xiamen University, Xiamen, Fujian Province, China,Department of Human Anatomy, School of Medicine, Xiamen University, Xiamen, Fujian Province, China
| | - Na Li
- The First Affiliated Hospital of Xiamen University-ICMRS Collaborating Centre for Skeletal Stem Cell, State Key Laboratory of Cellular Stress Biology, Faculty of Medicine and Life Sciences, Xiamen University, Xiamen, Fujian Province, China,Xiamen Key Laboratory of Regeneration Medicine, Fujian Provincial Key Laboratory of Organ and Tissue Regeneration, School of Medicine, School of Medicine, Xiamen University, Xiamen, Fujian Province, China,Department of Human Anatomy, School of Medicine, Xiamen University, Xiamen, Fujian Province, China,Corresponding authors: Ren Xu, ; Na Li,
| | - Ren Xu
- The First Affiliated Hospital of Xiamen University-ICMRS Collaborating Centre for Skeletal Stem Cell, State Key Laboratory of Cellular Stress Biology, Faculty of Medicine and Life Sciences, Xiamen University, Xiamen, Fujian Province, China,Xiamen Key Laboratory of Regeneration Medicine, Fujian Provincial Key Laboratory of Organ and Tissue Regeneration, School of Medicine, School of Medicine, Xiamen University, Xiamen, Fujian Province, China,Department of Human Anatomy, School of Medicine, Xiamen University, Xiamen, Fujian Province, China,Corresponding authors: Ren Xu, ; Na Li,
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13
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Brown S, Malik S, Aljammal M, O'Flynn A, Hobbs C, Shah M, Roberts SJ, Logan MPO. The Prrx1eGFP Mouse Labels the Periosteum During Development and a Subpopulation of Osteogenic Periosteal Cells in the Adult. JBMR Plus 2022; 7:e10707. [PMID: 36751415 PMCID: PMC9893263 DOI: 10.1002/jbm4.10707] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 10/06/2021] [Revised: 11/08/2022] [Accepted: 11/13/2022] [Indexed: 11/24/2022] Open
Abstract
The identity of the cells that form the periosteum during development is controversial with current dogma suggesting these are derived from a Sox9-positive progenitor. Herein, we characterize a newly created Prrx1eGFP reporter transgenic mouse line during limb formation and postnatally. Interestingly, in the embryo Prrx1eGFP-labeled cells become restricted around the Sox9-positive cartilage anlage without themselves becoming Sox9-positive. In the adult, the Prrx1eGFP transgene live labels a subpopulation of cells within the periosteum that are enriched at specific sites, and this population is diminished in aged mice. The green fluorescent protein (GFP)-labeled subpopulation can be isolated using fluorescence-activated cell sorting (FACS) and represents approximately 8% of all isolated periosteal cells. The GFP-labeled subpopulation is significantly more osteogenic than unlabeled, GFP-negative periosteal cells. In addition, the osteogenic and chondrogenic capacity of periosteal cells in vitro can be extended with the addition of fibroblast growth factor (FGF) to the expansion media. We provide evidence to suggest that osteoblasts contributing to cortical bone formation in the embryo originate from Prrx1eGFP-positive cells within the perichondrium, which possibly piggyback on invading vascular cells and secrete new bone matrix. In summary, the Prrx1eGFP mouse is a powerful tool to visualize and isolate periosteal cells and to quantify their properties in the embryo and adult. © 2022 The Authors. JBMR Plus published by Wiley Periodicals LLC on behalf of American Society for Bone and Mineral Research.
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Affiliation(s)
- Sarah Brown
- Randall Centre for Cell and Molecular BiophysicsKing's College LondonLondonUK
| | - Saif Malik
- Randall Centre for Cell and Molecular BiophysicsKing's College LondonLondonUK
| | - Maria Aljammal
- Randall Centre for Cell and Molecular BiophysicsKing's College LondonLondonUK
| | - Aine O'Flynn
- Randall Centre for Cell and Molecular BiophysicsKing's College LondonLondonUK
| | - Carl Hobbs
- Randall Centre for Cell and Molecular BiophysicsKing's College LondonLondonUK
| | | | - Scott J Roberts
- UCB PharmaSloughUK,Department of Comparative Biomedical SciencesRoyal Veterinary CollegeLondonUK
| | - Malcolm PO Logan
- Randall Centre for Cell and Molecular BiophysicsKing's College LondonLondonUK
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14
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Shah SS, Salo PT, Lyons FG, Mitha AP, Krawetz RJ. Prx1 + MPCs Accumulate in the Dura Mater of Wild-Type and p21 -/- Mice Followed by a Specific Reduction in p21 -/- Dural MPCs. Adv Biol (Weinh) 2022; 6:e2101304. [PMID: 36190137 DOI: 10.1002/adbi.202101304] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/16/2021] [Revised: 08/23/2022] [Indexed: 12/23/2022]
Abstract
Epidural fat contains a population of mesenchymal progenitor cells (MPCs), and this study explores the behavior of these cells on the adjacent dura mater during growth and in response to injury in a p21 knockout mouse model. p21-/- mice are known to have increased cell proliferation and enhanced tissue regeneration post-injury. Therefore, it is hypothesized that the process by which epidural fat MPCs maintain the dura mater can be accelerated in p21-/- mice. Using a Prx1 lineage tracing mouse model, the epidural fat MPCs are found to increase in the dura mater over time in both C57BL/6 (p21+/+ ) and p21-/- mice; however, by 3 weeks post-tamoxifen induction, few MPCs are observed in p21-/- mice. These endogenous MPCs also localize to dural injuries in both mouse strains, with MPCs in p21-/- mice demonstrating increased proliferation. When epidural fat MPCs derived from p21-/- mice are transplanted into dural injuries in C57BL/6 mice, these MPCs are found in the injury site. It is demonstrated that epidural fat MPCs play a role in dural tissue maintenance and are able to directly contribute to dural injury repair. This suggests that these MPCs have the potential to treat injuries and/or pathologies in tissues surrounding the spinal cord.
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Affiliation(s)
- Sophia S Shah
- McCaig Institute for Bone and Joint Health, University of Calgary, Calgary, AB, T2N 1N4, Canada.,Biomedical Engineering Graduate Program, University of Calgary, Calgary, AB, T2N 1N4, Canada
| | - Paul T Salo
- McCaig Institute for Bone and Joint Health, University of Calgary, Calgary, AB, T2N 1N4, Canada.,Department of Surgery, Cumming School of Medicine, University of Calgary, Calgary, AB, T2N 1N4, Canada
| | - Frank G Lyons
- McCaig Institute for Bone and Joint Health, University of Calgary, Calgary, AB, T2N 1N4, Canada
| | - Alim P Mitha
- Biomedical Engineering Graduate Program, University of Calgary, Calgary, AB, T2N 1N4, Canada.,Department of Clinical Neurosciences, Cumming School of Medicine, University of Calgary, Calgary, AB, T2N 1N4, Canada.,Hotchkiss Brain Institute, University of Calgary, Calgary, AB, T2N 1N4, Canada
| | - Roman J Krawetz
- McCaig Institute for Bone and Joint Health, University of Calgary, Calgary, AB, T2N 1N4, Canada.,Biomedical Engineering Graduate Program, University of Calgary, Calgary, AB, T2N 1N4, Canada.,Department of Surgery, Cumming School of Medicine, University of Calgary, Calgary, AB, T2N 1N4, Canada.,Department of Cell Biology and Anatomy, Cumming School of Medicine, University of Calgary, Calgary, AB, T2N 1N4, Canada
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15
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Ang PS, Matrongolo MJ, Zietowski ML, Nathan SL, Reid RR, Tischfield MA. Cranium growth, patterning and homeostasis. Development 2022; 149:dev201017. [PMID: 36408946 PMCID: PMC9793421 DOI: 10.1242/dev.201017] [Citation(s) in RCA: 2] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/22/2022]
Abstract
Craniofacial development requires precise spatiotemporal regulation of multiple signaling pathways that crosstalk to coordinate the growth and patterning of the skull with surrounding tissues. Recent insights into these signaling pathways and previously uncharacterized progenitor cell populations have refined our understanding of skull patterning, bone mineralization and tissue homeostasis. Here, we touch upon classical studies and recent advances with an emphasis on developmental and signaling mechanisms that regulate the osteoblast lineage for the calvaria, which forms the roof of the skull. We highlight studies that illustrate the roles of osteoprogenitor cells and cranial suture-derived stem cells for proper calvarial growth and homeostasis. We also discuss genes and signaling pathways that control suture patency and highlight how perturbing the molecular regulation of these pathways leads to craniosynostosis. Finally, we discuss the recently discovered tissue and signaling interactions that integrate skull and cerebrovascular development, and the potential implications for both cerebrospinal fluid hydrodynamics and brain waste clearance in craniosynostosis.
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Affiliation(s)
- Phillip S. Ang
- Department of Cell Biology and Neuroscience, Rutgers University, Piscataway, NJ 08854, USA
- University of Chicago Pritzker School of Medicine, Chicago, IL 60637, USA
| | - Matt J. Matrongolo
- Department of Cell Biology and Neuroscience, Rutgers University, Piscataway, NJ 08854, USA
- Child Health Institute of New Jersey, New Brunswick, NJ 08901, USA
| | | | - Shelby L. Nathan
- Laboratory of Craniofacial Biology and Development, Section of Plastic Surgery, Department of Surgery, University of Chicago Medicine, Chicago, IL 60637, USA
| | - Russell R. Reid
- Laboratory of Craniofacial Biology and Development, Section of Plastic Surgery, Department of Surgery, University of Chicago Medicine, Chicago, IL 60637, USA
| | - Max A. Tischfield
- Department of Cell Biology and Neuroscience, Rutgers University, Piscataway, NJ 08854, USA
- Child Health Institute of New Jersey, New Brunswick, NJ 08901, USA
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16
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Abstract
The tissue-resident skeletal stem cells (SSCs), which are self-renewal and multipotent, continuously provide cells (including chondrocytes, bone cells, marrow adipocytes, and stromal cells) for the development and homeostasis of the skeletal system. In recent decade, utilizing fluorescence-activated cell sorting, lineage tracing, and single-cell sequencing, studies have identified various types of SSCs, plotted the lineage commitment trajectory, and partially revealed their properties under physiological and pathological conditions. In this review, we retrospect to SSCs identification and functional studies. We discuss the principles and approaches to identify bona fide SSCs, highlighting pioneering findings that plot the lineage atlas of SSCs. The roles of SSCs and progenitors in long bone, craniofacial tissues, and periosteum are systematically discussed. We further focus on disputes and challenges in SSC research.
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17
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Xiao H, Zhang T, Li CJ, Cao Y, Wang LF, Chen HB, Li SC, Guan CB, Hu JZ, Chen D, Chen C, Lu HB. Mechanical stimulation promotes enthesis injury repair by mobilizing Prrx1+ cells via ciliary TGF-β signaling. eLife 2022; 11:73614. [PMID: 35475783 PMCID: PMC9094755 DOI: 10.7554/elife.73614] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/05/2021] [Accepted: 04/26/2022] [Indexed: 11/30/2022] Open
Abstract
Proper mechanical stimulation can improve rotator cuff enthesis injury repair. However, the underlying mechanism of mechanical stimulation promoting injury repair is still unknown. In this study, we found that Prrx1+ cell was essential for murine rotator cuff enthesis development identified by single-cell RNA sequence and involved in the injury repair. Proper mechanical stimulation could promote the migration of Prrx1+ cells to enhance enthesis injury repair. Meantime, TGF-β signaling and primary cilia played an essential role in mediating mechanical stimulation signaling transmission. Proper mechanical stimulation enhanced the release of active TGF-β1 to promote migration of Prrx1+ cells. Inhibition of TGF-β signaling eliminated the stimulatory effect of mechanical stimulation on Prrx1+ cell migration and enthesis injury repair. In addition, knockdown of Pallidin to inhibit TGF-βR2 translocation to the primary cilia or deletion of Ift88 in Prrx1+ cells also restrained the mechanics-induced Prrx1+ cells migration. These findings suggested that mechanical stimulation could increase the release of active TGF-β1 and enhance the mobilization of Prrx1+ cells to promote enthesis injury repair via ciliary TGF-β signaling.
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Affiliation(s)
- Han Xiao
- Department of Sports Medicine, Xiangya Hospital Central South University, Changsha, China
| | - Tao Zhang
- Department of Sports Medicine, Xiangya Hospital Central South University, Changsha, China
| | - Chang Jun Li
- Department of Endocrinology, Xiangya Hospital Central South University, Changsha, China
| | - Yong Cao
- Department of Spine Surgery, Xiangya Hospital Central South University, Changsha, China
| | - Lin Feng Wang
- Department of Sports Medicine, Xiangya Hospital Central South University, Changsha, China
| | - Hua Bin Chen
- Department of Sports Medicine, Xiangya Hospital Central South University, Changsha, China
| | - Sheng Can Li
- Department of Sports Medicine, Xiangya Hospital Central South University, Changsha, China
| | - Chang Biao Guan
- Department of Sports Medicine, Xiangya Hospital Central South University, Changsha, China
| | - Jian Zhong Hu
- Department of Spine Surgery, Xiangya Hospital Central South University, Changsha, China
| | - Di Chen
- Shenzhen Institute of Advanced Technology, Chinese Academy of Sciences, Shenzhen, China
| | - Can Chen
- Department of Orthopedic, Xiangya Hospital Central South University, Changsha, China
| | - Hong Bin Lu
- Department of Sports Medicine, Xiangya Hospital Central South University, Changsha, China
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18
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Zalama E, Karrouf G, Rizk A, Salama B, Samy A. Does zinc oxide nanoparticles potentiate the regenerative effect of platelet-rich fibrin in healing of critical bone defect in rabbits? BMC Vet Res 2022; 18:130. [PMID: 35366880 PMCID: PMC8976312 DOI: 10.1186/s12917-022-03231-6] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/05/2021] [Accepted: 03/15/2022] [Indexed: 11/20/2022] Open
Abstract
Background Many encouraging studies confirmed the ability of Zinc Oxide Nanoparticles (ZnONPs) in accelerating bone growth and mineralization. The use of Platelet Rich-Fibrin (PRF) as a sole filling material for large segmental bone defects remains questionable. The objectives are to investigate the regenerative efficacy of autologous Platelet Rich-Fibrin (PRF) and Zinc Oxide Nanoparticles (ZnONPs) in repairing large segmental bone ulnar defects in a randomized controlled study in rabbits using computed tomographic interpretations. A 12 mm critical size defect was surgically induced in the ulna of 30 rabbits (n = 10/ group). In the control group, the defect was left empty. In the PRF group, the defect is filled with PRF. In the PRF/ZnONPs group, the defect is filled with PRF that was inoculated with 0.1 ml of 0.2% ZnONPs. Radiologic healing capacity was evaluated at the first, second, and third postoperative months. Results Statistical analysis showed significant differences in the radiologic healing scores between the groups (P = 0.000–0.0001) at all-time points (P = 0.000–0.047) during the study. Conclusion Rabbits in the PRF/ZnONPs group showed the highest appreciable bone quality and quantity followed by the PRF group with high quantity but low bone quality meanwhile, rabbits in the control group showed minimal quantity but medium bone quality. Interestingly, the addition of ZnONPs to PRF can accelerate the healing of ulnar critical-size defects in rabbits.
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19
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Growth and mechanobiology of the tendon-bone enthesis. Semin Cell Dev Biol 2022; 123:64-73. [PMID: 34362655 PMCID: PMC8810906 DOI: 10.1016/j.semcdb.2021.07.015] [Citation(s) in RCA: 17] [Impact Index Per Article: 8.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/28/2021] [Revised: 07/17/2021] [Accepted: 07/20/2021] [Indexed: 12/15/2022]
Abstract
Tendons are cable-like connective tissues that transfer both active and passive forces generated by skeletal muscle to bone. In the mature skeleton, the tendon-bone enthesis is an interfacial zone of transitional tissue located between two mechanically dissimilar tissues: compliant, fibrous tendon to rigid, dense mineralized bone. In this review, we focus on emerging areas in enthesis development related to its structure, function, and mechanobiology, as well as highlight established and emerging signaling pathways and physiological processes that influence the formation and adaptation of this important transitional tissue.
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20
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Al Hosni R, Bozec L, Roberts SJ, Cheema U. Reprogramming bone progenitor identity and potency through control of collagen density and oxygen tension. iScience 2022; 25:104059. [PMID: 35345460 PMCID: PMC8957015 DOI: 10.1016/j.isci.2022.104059] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/10/2021] [Revised: 01/07/2022] [Accepted: 03/04/2022] [Indexed: 11/23/2022] Open
Abstract
The biophysical microenvironment of the cell is being increasingly used to control cell signaling and to direct cell function. Herein, engineered 3D tuneable biomimetic scaffolds are used to control the cell microenvironment of Adipose-derived Mesenchymal Stromal Cells (AMSC), which exhibit a collagen density-specific profile for early and late stage bone cell lineage status. Cell potency was enhanced when AMSCs were cultured within low collagen density environments in hypoxic conditions. A transitional culture containing varied collagen densities in hypoxic conditions directed differential cell fate responses. The early skeletal progenitor identity (PDPN+CD146−CD73+CD164+) was rescued in the cells which migrated into low collagen density gels, with cells continuously exposed to the high collagen density gels displaying a transitioned bone-cartilage-stromal phenotype (PDPN+CD146+CD73−CD164-). This study uncovers the significant contributions of the physical and physiological cell environment and highlights a chemically independent methodology for reprogramming and isolating skeletal progenitor cells from an adipose-derived cell population. Fabrication of a 3D transitional culture to control adipose-derived MSC (AMSC) fate AMSC potency is enhanced in low collagen density gels under hypoxic conditions Early skeletal progenitor identity of AMSCs is enriched in a low collagen density gel Bone-cartilage-stromal identity of AMSCs is enriched in a high collagen density gel
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21
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Birks S, Uzer G. At the nuclear envelope of bone mechanobiology. Bone 2021; 151:116023. [PMID: 34051417 PMCID: PMC8600447 DOI: 10.1016/j.bone.2021.116023] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 02/12/2021] [Revised: 05/11/2021] [Accepted: 05/21/2021] [Indexed: 02/06/2023]
Abstract
The nuclear envelope and nucleoskeleton are emerging as signaling centers that regulate how physical information from the extracellular matrix is biochemically transduced into the nucleus, affecting chromatin and controlling cell function. Bone is a mechanically driven tissue that relies on physical information to maintain its physiological function and structure. Disorder that present with musculoskeletal and cardiac symptoms, such as Emery-Dreifuss muscular dystrophies and progeria, correlate with mutations in nuclear envelope proteins including Linker of Nucleoskeleton and Cytoskeleton (LINC) complex, Lamin A/C, and emerin. However, the role of nuclear envelope mechanobiology on bone function remains underexplored. The mesenchymal stem cell (MSC) model is perhaps the most studied relationship between bone regulation and nuclear envelope function. MSCs maintain the musculoskeletal system by differentiating into multiple cell types including osteocytes and adipocytes, thus supporting the bone's ability to respond to mechanical challenge. In this review, we will focus on how MSC function is regulated by mechanical challenges both in vitro and in vivo within the context of bone function specifically focusing on integrin, β-catenin and YAP/TAZ signaling. The importance of the nuclear envelope will be explored within the context of musculoskeletal diseases related to nuclear envelope protein mutations and nuclear envelope regulation of signaling pathways relevant to bone mechanobiology in vitro and in vivo.
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Affiliation(s)
- Scott Birks
- Boise State University, Micron School of Materials Science and Engineering, United States of America
| | - Gunes Uzer
- Boise State University, Mechanical and Biomedical Engineering, United States of America.
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22
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Harris TL, Silva MJ. Gene expression of intracortical bone demonstrates loading-induced increases in Wnt1 and Ngf and inhibition of bone remodeling processes. Bone 2021; 150:116019. [PMID: 34023542 PMCID: PMC8408835 DOI: 10.1016/j.bone.2021.116019] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 01/24/2021] [Revised: 04/27/2021] [Accepted: 05/18/2021] [Indexed: 12/18/2022]
Abstract
Osteocytes are the primary mechanosensitive cells in bone. However, their location in mineralized matrix has limited the in vivo study of osteocytic genes induced by mechanical loading. Laser Capture Microdissection (LCM) allows isolation of intracortical bone (Intra-CB), enriched for osteocytes, from bone tissue for gene expression analysis. We used microarray to analyze gene expression from mouse tibial Intra-CB dissected using LCM 4 h after a single loading bout or after 5 days of loading. Osteocyte enrichment was supported by greater expression of Sost, Dmp1, Dkk1, and Mepe in Intra-CB regions vs. Mixed regions containing periosteum and muscle (fold-change (FC) = 3.4, 2.2, 5.1, 3.0, respectively). Over 150 differentially expressed genes (DEGs) due to loading (loaded vs. contralateral control) in Intra-CB were found on Day 1 and Day 5, but only 10 genes were differentially expressed on both days, including Ngf (Day 1 FC = 13.5, Day 5 FC = 11.1) and Wnt1 (Day 1 FC = 1.5, Day 5 FC = 5.1). The expression of Ngf and Wnt1 within Intra-CB was confirmed by in situ hybridization, and a significant increase in number of Wnt1 mRNA molecules occurred on day 1. We also found changes in extracellular matrix remodeling with Timp1 (FC = 3.1) increased on day 1 and MMP13 (FC = 0.3) decreased on day 5. Supporting this result, IHC for osteocytic MMP13 demonstrated a marginal decrease due to loading on day 5. Gene Ontology (GO) biological processes for loading DEGs indicated regulation of vasculature, neuronal and immune processes while cell-type specific gene lists suggested regulation of osteoclast, osteoblast, and endothelial related genes. In summary, microarray analysis of microdissected Intra-CB revealed differential regulation of Ngf, Wnt1, and MMP13 due to loading in osteocytes.
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Affiliation(s)
- Taylor L Harris
- Department of Orthopaedic Surgery and Musculoskeletal Research Center, Washington University School of Medicine, Saint Louis, MO, United States; Department of Biomedical Engineering, Washington University, Saint Louis, MO, United States.
| | - Matthew J Silva
- Department of Orthopaedic Surgery and Musculoskeletal Research Center, Washington University School of Medicine, Saint Louis, MO, United States
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23
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Couasnay G, Madel MB, Lim J, Lee B, Elefteriou F. Sites of Cre-recombinase activity in mouse lines targeting skeletal cells. J Bone Miner Res 2021; 36:1661-1679. [PMID: 34278610 DOI: 10.1002/jbmr.4415] [Citation(s) in RCA: 10] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 03/30/2021] [Revised: 07/12/2021] [Accepted: 07/15/2021] [Indexed: 12/22/2022]
Abstract
The Cre/Lox system is a powerful tool in the biologist's toolbox, allowing loss-of-function and gain-of-function studies, as well as lineage tracing, through gene recombination in a tissue-specific and inducible manner. Evidence indicates, however, that Cre transgenic lines have a far more nuanced and broader pattern of Cre activity than initially thought, exhibiting "off-target" activity in tissues/cells other than the ones they were originally designed to target. With the goal of facilitating the comparison and selection of optimal Cre lines to be used for the study of gene function, we have summarized in a single manuscript the major sites and timing of Cre activity of the main Cre lines available to target bone mesenchymal stem cells, chondrocytes, osteoblasts, osteocytes, tenocytes, and osteoclasts, along with their reported sites of "off-target" Cre activity. We also discuss characteristics, advantages, and limitations of these Cre lines for users to avoid common risks related to overinterpretation or misinterpretation based on the assumption of strict cell-type specificity or unaccounted effect of the Cre transgene or Cre inducers. © 2021 American Society for Bone and Mineral Research (ASBMR).
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Affiliation(s)
- Greig Couasnay
- Department of Orthopedic Surgery, Baylor College of Medicine, Houston, TX, USA
| | | | - Joohyun Lim
- Department of Molecular and Human Genetics, Baylor College of Medicine, Houston, TX, USA
| | - Brendan Lee
- Department of Molecular and Human Genetics, Baylor College of Medicine, Houston, TX, USA
| | - Florent Elefteriou
- Department of Orthopedic Surgery, Baylor College of Medicine, Houston, TX, USA.,Department of Molecular and Human Genetics, Baylor College of Medicine, Houston, TX, USA
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24
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Qu C, He L, Yao N, Li J, Jiang Y, Li B, Peng S, Hu K, Chen D, Chen G, Huang W, Cao M, Fan J, Yuan Y, Ye W, Hong J. Myofibroblast-Specific Msi2 Knockout Inhibits HCC Progression in a Mouse Model. Hepatology 2021; 74:458-473. [PMID: 33609283 DOI: 10.1002/hep.31754] [Citation(s) in RCA: 11] [Impact Index Per Article: 3.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 09/09/2020] [Revised: 12/31/2020] [Accepted: 01/11/2021] [Indexed: 12/24/2022]
Abstract
BACKGROUND AND AIMS Myofibroblasts play a pivotal role in the development and progression of HCC. Here, we aimed to explore the role and mechanism of myofibroblast Musashi RNA binding protein 2 (MSI2) in HCC progression. APPROACH AND RESULTS Myofibroblast infiltration and collagen deposition were detected and assessed in the tissues from 117 patients with HCC. Transgenic mice (Msi2ΔCol1a1 ) with floxed Msi2 allele and collagen type I alpha 1 chain (Col1a1)-ligand inducible Cre recombinases (CreER) were constructed to generate a myofibroblast-specific Msi2 knockout model. Mouse HCC cells were orthotopically transplanted into the Msi2ΔCol1a1 or the control mice (Msi2F/F ). We found that the deposition of collagen fibers, the main product of myofibroblasts, predicted a poor prognosis for HCC; meanwhile, we detected high MSI2 expression in the peritumoral infiltrated myofibroblasts. Conditional deletion of Msi2 in myofibroblasts significantly inhibited the growth of orthotopically implanted HCC, reduced both intrahepatic and lung metastasis, and prolonged the overall survival of tumor-bearing mice (P = 0.002). In vitro analysis demonstrated that myofibroblasts promoted cell proliferation, invasion, and epithelial-mesenchymal transformation of HCC cells, whereas Msi2 deletion in myofibroblasts reversed these effects. Mechanically, Msi2 knockout decreased myofibroblast-derived IL-6 and IL-11 secretion by inhibiting the extracellular signal-regulated kinase 1/2 pathway, and thus attenuated the cancer stem cell-promoting effect of myofibroblasts. Interestingly, we found that the simultaneous knockout of Msi2 in myofibroblasts and knockdown of Msi2 in HCC cells could not further attenuate the implanted HCC progression. CONCLUSIONS Myofibroblast-specific Msi2 knockout abrogated the tumor-promoting function of myofibroblasts and inhibited HCC progression in mouse models. Targeting myofibroblast MSI2 expression may therefore prove to be a therapeutic strategy for HCC treatment in the future.
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Affiliation(s)
- Chen Qu
- Department of Pathophysiology, School of Medicine, Jinan University, Guangzhou, China
| | - Lu He
- Department of Radiotherapy, Affiliated Cancer Hospital & Institute of Guangzhou Medical University, Guangzhou, China.,Integrated Hospital of Traditional Chinese Medicine, Southern Medical University, Guangzhou, China
| | - Nan Yao
- College of Pharmacy, Jinan University, Guangzhou, China
| | - Jinying Li
- Department of Gastroenterology, The First Affiliated Hospital of Jinan University, Guangzhou, China
| | - Yuchuan Jiang
- Department of Hepatological Surgery, The First Affiliated Hospital of Jinan University, Guangzhou, China
| | - Binkui Li
- State Key Laboratory of Oncology in South China, Sun Yat-sen University Cancer Center, Guangzhou, China.,Department of Hepatobiliary Oncology, Sun Yat-sen University Cancer Center, Guangzhou, China
| | - Shuang Peng
- Department of Pathophysiology, School of Medicine, Jinan University, Guangzhou, China
| | - Kunpeng Hu
- Department of General Surgery, The Third Affiliated Hospital of Sun Yat-sen University, Guangzhou, China
| | - Dong Chen
- Department of Pancreato-Biliary Surgery, The First Affiliated Hospital of Sun Yat-sen University, Guangzhou, China
| | - Guo Chen
- Department of Biochemistry, School of Medicine, Jinan University, Guangzhou, China
| | - Wei Huang
- Department of Gastroenterology, The First Affiliated Hospital of Jinan University, Guangzhou, China
| | - Mingrong Cao
- Department of Hepatological Surgery, The First Affiliated Hospital of Jinan University, Guangzhou, China
| | - Jun Fan
- Department of Biochemistry, School of Medicine, Jinan University, Guangzhou, China
| | - Yunfei Yuan
- State Key Laboratory of Oncology in South China, Sun Yat-sen University Cancer Center, Guangzhou, China.,Department of Hepatobiliary Oncology, Sun Yat-sen University Cancer Center, Guangzhou, China
| | - Wencai Ye
- College of Pharmacy, Jinan University, Guangzhou, China
| | - Jian Hong
- Department of Pathophysiology, School of Medicine, Jinan University, Guangzhou, China.,Integrated Hospital of Traditional Chinese Medicine, Southern Medical University, Guangzhou, China.,Department of Hepatological Surgery, The First Affiliated Hospital of Jinan University, Guangzhou, China
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25
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Xie Z, McGrath C, Sankaran J, Styner M, Little-Letsinger S, Dudakovic A, van Wijnen AJ, Rubin J, Sen B. Low-Dose Tamoxifen Induces Significant Bone Formation in Mice. JBMR Plus 2021; 5:e10450. [PMID: 33778320 PMCID: PMC7990151 DOI: 10.1002/jbm4.10450] [Citation(s) in RCA: 9] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 09/21/2020] [Revised: 10/29/2020] [Accepted: 11/02/2020] [Indexed: 12/31/2022] Open
Abstract
Use of the selective estrogen receptor modulator Tamoxifen (TAM) is a mainstay to induce conditional expression of Cre recombinase in transgenic laboratory mice. To excise β‐cateninfl/fl in 28‐day‐old male and female Prrx1‐CreER/β‐cateninfl/fl mice (C57BL/6), we utilized TAM at 150 mg/kg; despite β‐catenin knockout in MSC, we found a significant increase in trabecular and cortical bone volume in all genders. Because TAM was similarly anabolic in KO and control mice, we investigated a dose effect on bone formation by treating wild‐type mice (WT C57BL/6, 4 weeks) with TAM (total dose 0, 20, 40, 200 mg/kg via four injections). TAM increased bone in a dose‐dependent manner analyzed by micro–computed tomography (μCT), which showed that, compared to control, 20 mg/kg TAM increased femoral bone volume fraction (bone volume/total volume [BV/TV]) (21.6% ± 1.5% to 33% ± 2.5%; 153%, p < 0.005). With TAM 40 mg/kg and 200 mg/kg, BV/TV increased to 48.1% ± 4.4% (223%, p < 0.0005) and 58% ± 3.8% (269%, p < 0.0001) respectively, compared to control. Osteoblast markers increased with 200 mg/kg TAM: Dlx5 (224%, p < 0.0001), Alp (166%, p < 0.0001), Bglap (223%, p < 0.0001), and Sp7 (228%, p < 0.0001). Osteoclasts per bone surface (Oc#/BS) nearly doubled at the lowest TAM dose (20 mg/kg), but decreased to <20% control with 200 mg/kg TAM. Our data establish that use of TAM at even very low doses to excise a floxed target in postnatal mice has profound effects on trabecular and cortical bone formation. As such, TAM treatment is a major confounder in the interpretation of bone phenotypes in conditional gene knockout mouse models. © 2020 The Authors. JBMR Plus published by Wiley Periodicals LLC. on behalf of American Society for Bone and Mineral Research.
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Affiliation(s)
- Zhihui Xie
- Department of Medicine University of North Carolina Chapel Hill NC USA
| | - Cody McGrath
- Department of Medicine University of North Carolina Chapel Hill NC USA
| | - Jeyantt Sankaran
- Department of Medicine University of North Carolina Chapel Hill NC USA
| | - Maya Styner
- Department of Medicine University of North Carolina Chapel Hill NC USA
| | | | - Amel Dudakovic
- Department of Orthopedic Surgery and Biochemistry and Molecular Biology Mayo Clinic Rochester MN USA
| | - Andre J van Wijnen
- Department of Orthopedic Surgery and Biochemistry and Molecular Biology Mayo Clinic Rochester MN USA
| | - Janet Rubin
- Department of Medicine University of North Carolina Chapel Hill NC USA
| | - Buer Sen
- Department of Medicine University of North Carolina Chapel Hill NC USA
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26
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Oliveira TC, Gomes MS, Gomes AC. The Crossroads between Infection and Bone Loss. Microorganisms 2020; 8:microorganisms8111765. [PMID: 33182721 PMCID: PMC7698271 DOI: 10.3390/microorganisms8111765] [Citation(s) in RCA: 16] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/20/2020] [Revised: 11/05/2020] [Accepted: 11/09/2020] [Indexed: 01/18/2023] Open
Abstract
Bone homeostasis, based on a tight balance between bone formation and bone degradation, is affected by infection. On one hand, some invading pathogens are capable of directly colonizing the bone, leading to its destruction. On the other hand, immune mediators produced in response to infection may dysregulate the deposition of mineral matrix by osteoblasts and/or the resorption of bone by osteoclasts. Therefore, bone loss pathologies may develop in response to infection, and their detection and treatment are challenging. Possible biomarkers of impaired bone metabolism during chronic infection need to be identified to improve the diagnosis and management of infection-associated osteopenia. Further understanding of the impact of infections on bone metabolism is imperative for the early detection, prevention, and/or reversion of bone loss. Here, we review the mechanisms responsible for bone loss as a direct and/or indirect consequence of infection.
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Affiliation(s)
- Tiago Carvalho Oliveira
- i3S—Instituto de Investigação e Inovação em Saúde, Universidade do Porto, 4200-135 Porto, Portugal; (T.C.O.); (M.S.G.)
- Faculdade de Ciências da Universidade do Porto, 4169-007 Porto, Portugal
- Instituto de Ciências Biomédicas de Abel Salazar da Universidade do Porto, 4050-313 Porto, Portugal
| | - Maria Salomé Gomes
- i3S—Instituto de Investigação e Inovação em Saúde, Universidade do Porto, 4200-135 Porto, Portugal; (T.C.O.); (M.S.G.)
- Instituto de Ciências Biomédicas de Abel Salazar da Universidade do Porto, 4050-313 Porto, Portugal
| | - Ana Cordeiro Gomes
- i3S—Instituto de Investigação e Inovação em Saúde, Universidade do Porto, 4200-135 Porto, Portugal; (T.C.O.); (M.S.G.)
- Correspondence:
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27
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Huang S, Jin M, Su N, Chen L. New insights on the reparative cells in bone regeneration and repair. Biol Rev Camb Philos Soc 2020; 96:357-375. [PMID: 33051970 DOI: 10.1111/brv.12659] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/01/2020] [Revised: 10/06/2020] [Accepted: 10/07/2020] [Indexed: 12/14/2022]
Abstract
Bone possesses a remarkable repair capacity to regenerate completely without scar tissue formation. This unique characteristic, expressed during bone development, maintenance and injury (fracture) healing, is performed by the reparative cells including skeletal stem cells (SSCs) and their descendants. However, the identity and functional roles of SSCs remain controversial due to technological difficulties and the heterogeneity and plasticity of SSCs. Moreover, for many years, there has been a biased view that bone marrow is the main cell source for bone repair. Together, these limitations have greatly hampered our understanding of these important cell populations and their potential applications in the treatment of fractures and skeletal diseases. Here, we reanalyse and summarize current understanding of the reparative cells in bone regeneration and repair and outline recent progress in this area, with a particular emphasis on the temporal and spatial process of fracture healing, the sources of reparative cells, an updated definition of SSCs, and markers of skeletal stem/progenitor cells contributing to the repair of craniofacial and long bones, as well as the debate between SSCs and pericytes. Finally, we also discuss the existing problems, emerging novel technologies and future research directions in this field.
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Affiliation(s)
- Shuo Huang
- Department of Wound Repair and Rehabilitation Medicine, Center of Bone Metabolism and Repair, State Key Laboratory of Trauma, Burns and Combined Injury, Trauma Center, Research Institute of Surgery, Daping Hospital, Army Medical University (Third Military Medical University), 10 Changjiang zhi Road, Yuzhong District, Chongqing, China
| | - Min Jin
- Department of Wound Repair and Rehabilitation Medicine, Center of Bone Metabolism and Repair, State Key Laboratory of Trauma, Burns and Combined Injury, Trauma Center, Research Institute of Surgery, Daping Hospital, Army Medical University (Third Military Medical University), 10 Changjiang zhi Road, Yuzhong District, Chongqing, China
| | - Nan Su
- Department of Wound Repair and Rehabilitation Medicine, Center of Bone Metabolism and Repair, State Key Laboratory of Trauma, Burns and Combined Injury, Trauma Center, Research Institute of Surgery, Daping Hospital, Army Medical University (Third Military Medical University), 10 Changjiang zhi Road, Yuzhong District, Chongqing, China
| | - Lin Chen
- Department of Wound Repair and Rehabilitation Medicine, Center of Bone Metabolism and Repair, State Key Laboratory of Trauma, Burns and Combined Injury, Trauma Center, Research Institute of Surgery, Daping Hospital, Army Medical University (Third Military Medical University), 10 Changjiang zhi Road, Yuzhong District, Chongqing, China
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28
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Esposito A, Wang L, Li T, Miranda M, Spagnoli A. Role of Prx1-expressing skeletal cells and Prx1-expression in fracture repair. Bone 2020; 139:115521. [PMID: 32629173 PMCID: PMC7484205 DOI: 10.1016/j.bone.2020.115521] [Citation(s) in RCA: 26] [Impact Index Per Article: 6.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 02/17/2020] [Revised: 06/25/2020] [Accepted: 06/29/2020] [Indexed: 12/22/2022]
Abstract
The healing capacity of bones after fracture implies the existence of adult regenerative cells. However, information on identification and functional role of fracture-induced progenitors is still lacking. Paired-related homeobox 1 (Prx1) is expressed during skeletogenesis. We hypothesize that fracture recapitulates Prx1's expression, and Prx1 expressing cells are critical to induce repair. To address our hypothesis, we used a combination of in vivo and in vitro approaches, short and long-term cell tracking analyses of progenies and actively expressing cells, cell ablation studies, and rodent animal models for normal and defective fracture healing. We found that fracture elicits a periosteal and endosteal response of perivascular Prx1+ cells that participate in fracture healing and showed that Prx1-expressing cells have a functional role in the repair process. While Prx1-derived cells contribute to the callus, Prx1's expression decreases concurrently with differentiation into cartilaginous and bone cells, similarly to when Prx1+ cells are cultured in differentiating conditions. We determined that bone morphogenic protein 2 (BMP2), through C-X-C motif-ligand-12 (CXCL12) signaling, modulates the downregulation of Prx1. We demonstrated that fracture elicits an early increase in BMP2 expression, followed by a decrease in CXCL12 that in turn down-regulates Prx1, allowing cells to commit to osteochondrogenesis. In vivo and in vitro treatment with CXCR4 antagonist AMD3100 restored Prx1 expression by modulating the BMP2-CXCL12 axis. Our studies represent a shift in the current research that has primarily focused on the identification of markers for postnatal skeletal progenitors, and instead we characterized the function of a specific population (Prx1+ cells) and their expression marker (Prx1) as a crossroad in fracture repair. The identification of fracture-induced perivascular Prx1+ cells and regulation of Prx1's expression by BMP2 and in turn by CXCL12 in the orchestration of fracture repair, highlights a pathway in which to investigate defective mechanisms and therapeutic targets for fracture non-union.
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Affiliation(s)
- Alessandra Esposito
- Department of Orthopaedic Surgery, Section of Molecular Medicine, Rush University Medical Center, Chicago, IL, USA
| | - Lai Wang
- Department of Internal Medicine, Division of Rheumatology, Rush University Medical Center, Chicago, IL, USA
| | - Tieshi Li
- Department of Pediatrics, University of Nebraska Medical Center, Children's Hospital & Medical Center, Omaha, NE, USA
| | - Mariana Miranda
- Department of Orthopaedic Surgery, Section of Molecular Medicine, Rush University Medical Center, Chicago, IL, USA
| | - Anna Spagnoli
- Department of Orthopaedic Surgery, Section of Molecular Medicine, Rush University Medical Center, Chicago, IL, USA; Department of Pediatrics, Division of Pediatric Endocrinology, Rush University Medical Center, Chicago, IL, USA.
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29
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Ortinau L, Lei K, Jeong Y, Park D. Real-Time Imaging of CCL5-Induced Migration of Periosteal Skeletal Stem Cells in Mice. J Vis Exp 2020:10.3791/61162. [PMID: 33016934 PMCID: PMC9119154 DOI: 10.3791/61162] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/31/2022] Open
Abstract
Periosteal skeletal stem cells (P-SSCs) are essential for lifelong bone maintenance and repair, making them an ideal focus for the development of therapies to enhance fracture healing. Periosteal cells rapidly migrate to an injury to supply new chondrocytes and osteoblasts for fracture healing. Traditionally, the efficacy of a cytokine to induce cell migration has only been conducted in vitro by performing a transwell or scratch assay. With advancements in intravital microscopy using multiphoton excitation, it was recently discovered that 1) P-SSCs express the migratory gene CCR5 and 2) treatment with the CCR5 ligand known as CCL5 improves fracture healing and the migration of P-SSCs in response to CCL5. These results have been captured in real-time. Described here is a protocol to visualize P-SSC migration from the calvarial suture skeletal stem cell (SSC) niche towards an injury after treatment with CCL5. The protocol details the construction of a mouse restraint and imaging mount, surgical preparation of the mouse calvaria, induction of a calvaria defect, and acquisition of time-lapse imaging.
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Affiliation(s)
- Laura Ortinau
- Department of Molecular & Human Genetics, Baylor College of Medicine; Center for Skeletal Biology, Baylor College of Medicine
| | - Kevin Lei
- Department of Molecular & Human Genetics, Baylor College of Medicine
| | - Youngjae Jeong
- Department of Molecular & Human Genetics, Baylor College of Medicine
| | - Dongsu Park
- Department of Molecular & Human Genetics, Baylor College of Medicine; Center for Skeletal Biology, Baylor College of Medicine; Department of Pathology & Immunology, Baylor College of Medicine;
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30
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Xiao H, Wang L, Zhang T, Chen C, Chen H, Li S, Hu J, Lu H. Periosteum progenitors could stimulate bone regeneration in aged murine bone defect model. J Cell Mol Med 2020; 24:12199-12210. [PMID: 32931157 PMCID: PMC7579685 DOI: 10.1111/jcmm.15891] [Citation(s) in RCA: 13] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/19/2020] [Revised: 08/20/2020] [Accepted: 08/28/2020] [Indexed: 12/12/2022] Open
Abstract
Periosteal stem cells are critical for bone regeneration, while the numbers will decrease with age. This study focused on whether Prx1+ cell, a kind of periosteal stem cell, could stimulate bone regeneration in aged mice. Four weeks and 12 months old Prx1CreER‐GFP; Rosa26tdTomato mice were used to reveal the degree of Prx1+ cells participating in the femoral fracture healing procedure. One week, 8 weeks, 12 and 24 months old Prx1CreER‐GFP mice were used to analyse the real‐time distribution of Prx1+ cells. Twelve months old C57BL/6 male mice (n = 96) were used to create the bone defect model and, respectively, received hydrogel, hydrogel with Prx1− mesenchymal stem cells and hydrogel with Prx1+ cells. H&E staining, Synchrotron radiation‐microcomputed tomography and mechanical test were used to analyse the healing results. The results showed that tdTomato+ cells were involved in bone regeneration, especially in young mice. At the same time, GFP+ cells decreased significantly with age. The Prx1+ cells group could significantly improve bone regeneration in the murine bone defect model via directly differentiating into osteoblasts and had better osteogenic differentiation ability than Prx1− mesenchymal stem cells. Our finding revealed that the quantity of Prx1+ cells might account for decreased bone regeneration ability in aged mice, and transplantation of Prx1+ cells could improve bone regeneration at the bone defect site.
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Affiliation(s)
- Han Xiao
- Department of Sports Medicine, Xiangya Hospital, Central South University, Changsha, China.,Key Laboratory of Organ Injury, Aging and Regenerative Medicine of Hunan Province, Changsha, China.,Xiangya Hospital-International Chinese Musculoskeletal Research Society Sports Medicine Research Centre, Changsha, China.,Hunan Engineering Research Center of Sport and Health, Changsha, China
| | - Linfeng Wang
- Department of Sports Medicine, Xiangya Hospital, Central South University, Changsha, China.,Key Laboratory of Organ Injury, Aging and Regenerative Medicine of Hunan Province, Changsha, China.,Xiangya Hospital-International Chinese Musculoskeletal Research Society Sports Medicine Research Centre, Changsha, China.,Hunan Engineering Research Center of Sport and Health, Changsha, China
| | - Tao Zhang
- Department of Sports Medicine, Xiangya Hospital, Central South University, Changsha, China.,Key Laboratory of Organ Injury, Aging and Regenerative Medicine of Hunan Province, Changsha, China.,Xiangya Hospital-International Chinese Musculoskeletal Research Society Sports Medicine Research Centre, Changsha, China.,Hunan Engineering Research Center of Sport and Health, Changsha, China
| | - Can Chen
- Department of Sports Medicine, Xiangya Hospital, Central South University, Changsha, China.,Key Laboratory of Organ Injury, Aging and Regenerative Medicine of Hunan Province, Changsha, China.,Xiangya Hospital-International Chinese Musculoskeletal Research Society Sports Medicine Research Centre, Changsha, China.,Hunan Engineering Research Center of Sport and Health, Changsha, China
| | - Huabin Chen
- Department of Sports Medicine, Xiangya Hospital, Central South University, Changsha, China.,Key Laboratory of Organ Injury, Aging and Regenerative Medicine of Hunan Province, Changsha, China.,Xiangya Hospital-International Chinese Musculoskeletal Research Society Sports Medicine Research Centre, Changsha, China.,Hunan Engineering Research Center of Sport and Health, Changsha, China
| | - Shengcan Li
- Department of Sports Medicine, Xiangya Hospital, Central South University, Changsha, China.,Key Laboratory of Organ Injury, Aging and Regenerative Medicine of Hunan Province, Changsha, China.,Xiangya Hospital-International Chinese Musculoskeletal Research Society Sports Medicine Research Centre, Changsha, China.,Hunan Engineering Research Center of Sport and Health, Changsha, China
| | - Jianzhong Hu
- Key Laboratory of Organ Injury, Aging and Regenerative Medicine of Hunan Province, Changsha, China.,Xiangya Hospital-International Chinese Musculoskeletal Research Society Sports Medicine Research Centre, Changsha, China.,Hunan Engineering Research Center of Sport and Health, Changsha, China.,Department of Spine Surgery, Xiangya Hospital, Central South University, Changsha, China
| | - Hongbin Lu
- Department of Sports Medicine, Xiangya Hospital, Central South University, Changsha, China.,Key Laboratory of Organ Injury, Aging and Regenerative Medicine of Hunan Province, Changsha, China.,Xiangya Hospital-International Chinese Musculoskeletal Research Society Sports Medicine Research Centre, Changsha, China.,Hunan Engineering Research Center of Sport and Health, Changsha, China
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31
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Ortinau LC, Wang H, Lei K, Deveza L, Jeong Y, Hara Y, Grafe I, Rosenfeld SB, Lee D, Lee B, Scadden DT, Park D. Identification of Functionally Distinct Mx1+αSMA+ Periosteal Skeletal Stem Cells. Cell Stem Cell 2020; 25:784-796.e5. [PMID: 31809737 DOI: 10.1016/j.stem.2019.11.003] [Citation(s) in RCA: 115] [Impact Index Per Article: 28.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/03/2019] [Revised: 09/11/2019] [Accepted: 11/11/2019] [Indexed: 12/21/2022]
Abstract
The periosteum is critical for bone maintenance and healing. However, the in vivo identity and specific regulatory mechanisms of adult periosteum-resident skeletal stem cells are unknown. Here, we report animal models that selectively and durably label postnatal Mx1+αSMA+ periosteal stem cells (P-SSCs) and establish that P-SSCs are a long-term repopulating, functionally distinct SSC subset responsible for lifelong generation of periosteal osteoblasts. P-SSCs rapidly migrate toward an injury site, supply osteoblasts and chondrocytes, and recover new periosteum. Notably, P-SSCs specifically express CCL5 receptors, CCR3 and CCR5. Real-time intravital imaging revealed that the treatment with CCL5 induces P-SSC migration in vivo and bone healing, while CCL5/CCR5 deletion, CCR5 inhibition, or local P-SSC ablation reduces osteoblast number and delays bone healing. Human periosteal cells express CCR5 and undergo CCL5-mediated migration. Thus, the adult periosteum maintains genetically distinct SSC subsets with a CCL5-dependent migratory mechanism required for bone maintenance and injury repair.
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Affiliation(s)
- Laura C Ortinau
- Department of Molecular Human Genetics, Baylor College of Medicine, One Baylor Plaza, Houston, TX 77030, USA; Center for Skeletal Biology, Baylor College of Medicine, One Baylor Plaza, Houston, TX 77030, USA
| | - Hamilton Wang
- Department of Molecular Human Genetics, Baylor College of Medicine, One Baylor Plaza, Houston, TX 77030, USA
| | - Kevin Lei
- Department of Molecular Human Genetics, Baylor College of Medicine, One Baylor Plaza, Houston, TX 77030, USA
| | - Lorenzo Deveza
- Department of Orthopedic Surgery, Baylor College of Medicine, One Baylor Plaza, Houston, TX 77030, USA
| | - Youngjae Jeong
- Department of Molecular Human Genetics, Baylor College of Medicine, One Baylor Plaza, Houston, TX 77030, USA
| | - Yannis Hara
- Department of Molecular Human Genetics, Baylor College of Medicine, One Baylor Plaza, Houston, TX 77030, USA
| | - Ingo Grafe
- Department of Molecular Human Genetics, Baylor College of Medicine, One Baylor Plaza, Houston, TX 77030, USA; Center for Skeletal Biology, Baylor College of Medicine, One Baylor Plaza, Houston, TX 77030, USA
| | - Scott B Rosenfeld
- Texas Children's Hospital, 6701 Fannin Street, Houston, TX 77030, USA
| | - Dongjun Lee
- Department of Convergence of Medical Science, Pusan National University School of Medicine, Yangsan 50612, Republic of Korea
| | - Brendan Lee
- Department of Molecular Human Genetics, Baylor College of Medicine, One Baylor Plaza, Houston, TX 77030, USA; Center for Skeletal Biology, Baylor College of Medicine, One Baylor Plaza, Houston, TX 77030, USA
| | - David T Scadden
- Harvard Stem Cell Institute, Harvard University, 7 Divinity Avenue, Cambridge, MA 02138, USA; Department of Stem Cell and Regenerative Biology, Harvard University, 7 Divinity Avenue, Cambridge, MA 02138, USA
| | - Dongsu Park
- Department of Molecular Human Genetics, Baylor College of Medicine, One Baylor Plaza, Houston, TX 77030, USA; Center for Skeletal Biology, Baylor College of Medicine, One Baylor Plaza, Houston, TX 77030, USA; Department of Pathology and Immunology, Baylor College of Medicine, One Baylor Plaza, Houston, TX 77030, USA.
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Ko FC, Sumner DR. How faithfully does intramembranous bone regeneration recapitulate embryonic skeletal development? Dev Dyn 2020; 250:377-392. [PMID: 32813296 DOI: 10.1002/dvdy.240] [Citation(s) in RCA: 16] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/01/2020] [Revised: 07/19/2020] [Accepted: 08/13/2020] [Indexed: 02/06/2023] Open
Abstract
Postnatal intramembranous bone regeneration plays an important role during a wide variety of musculoskeletal regeneration processes such as fracture healing, joint replacement and dental implant surgery, distraction osteogenesis, stress fracture healing, and repair of skeletal defects caused by trauma or resection of tumors. The molecular basis of intramembranous bone regeneration has been interrogated using rodent models of most of these conditions. These studies reveal that signaling pathways such as Wnt, TGFβ/BMP, FGF, VEGF, and Notch are invoked, reminiscent of embryonic development of membranous bone. Discoveries of several skeletal stem cell/progenitor populations using mouse genetic models also reveal the potential sources of postnatal intramembranous bone regeneration. The purpose of this review is to compare the underlying molecular signals and progenitor cells that characterize embryonic development of membranous bone and postnatal intramembranous bone regeneration.
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Affiliation(s)
- Frank C Ko
- Department of Cell & Molecular Medicine, Rush University Medical Center, Chicago, Illinois, USA
| | - D Rick Sumner
- Department of Cell & Molecular Medicine, Rush University Medical Center, Chicago, Illinois, USA
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Al Hosni R, Shah M, Cheema U, Roberts HC, Luyten FP, Roberts SJ. Mapping human serum-induced gene networks as a basis for the creation of biomimetic periosteum for bone repair. Cytotherapy 2020; 22:424-435. [PMID: 32522398 DOI: 10.1016/j.jcyt.2020.03.434] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/05/2019] [Revised: 02/21/2020] [Accepted: 03/23/2020] [Indexed: 12/15/2022]
Abstract
BACKGROUND The periosteum is a highly vascularized, collagen-rich tissue that plays a crucial role in directing bone repair. This is orchestrated primarily by its resident progenitor cell population. Indeed, preservation of periosteum integrity is critical for bone healing. Cells extracted from the periosteum retain their osteochondrogenic properties and as such are a promising basis for tissue engineering strategies for the repair of bone defects. However, the culture expansion conditions and the way in which the cells are reintroduced to the defect site are critical aspects of successful translation. Indeed, expansion in human serum and implantation on biomimetic materials has previously been shown to improve in vivo bone formation. AIM This study aimed to develop a protocol to allow for the expansion of human periosteum derived cells (hPDCs) in a biomimetic periosteal-like environment. METHODS The expansion conditions were defined through the investigation of the bioactive cues involved in augmenting hPDC proliferative and multipotency characteristics, based on transcriptomic analysis of cells cultured in human serum. RESULTS Master regulators of transcriptional networks were identified, and an optimized periosteum-derived growth factor cocktail (PD-GFC; containing β-estradiol, FGF2, TNFα, TGFβ, IGF-1 and PDGF-BB) was generated. Expansion of hPDCs in PD-GFC resulted in serum mimicry with regard to the cell morphology, proliferative capacity and chondrogenic differentiation. When incorporated into a three-dimensional collagen type 1 matrix and cultured in PD-GFC, the hPDCs migrated to the surface that represented the matrix topography of the periosteum cambium layer. Furthermore, gene expression analysis revealed a down-regulated WNT and TGFβ signature and an up-regulation of CREB, which may indicate the hPDCs are recreating their progenitor cell signature. CONCLUSION This study highlights the first stage in the development of a biomimetic periosteum, which may have applications in bone repair.
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Affiliation(s)
- Rawiya Al Hosni
- Department of Materials and Tissue, Institute of Orthopaedics and Musculoskeletal Science, University College London, Stanmore, UK
| | - Mittal Shah
- Department of Materials and Tissue, Institute of Orthopaedics and Musculoskeletal Science, University College London, Stanmore, UK
| | - Umber Cheema
- Department of Materials and Tissue, Institute of Orthopaedics and Musculoskeletal Science, University College London, Stanmore, UK
| | - Helen C Roberts
- Department of Natural Sciences, Faculty of Science & Technology, Middlesex University, London, UK
| | - Frank P Luyten
- Skeletal Biology and Tissue Engineering Centre, Department of Development and Regeneration, KU Leuven, Leuven, Belgium and
| | - Scott J Roberts
- Department of Materials and Tissue, Institute of Orthopaedics and Musculoskeletal Science, University College London, Stanmore, UK; Skeletal Biology and Tissue Engineering Centre, Department of Development and Regeneration, KU Leuven, Leuven, Belgium and; Department of Comparative Biomedical Sciences, The Royal Veterinary College, London, UK.
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34
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Xu GP, Zhang XF, Sun L, Chen EM. Current and future uses of skeletal stem cells for bone regeneration. World J Stem Cells 2020; 12:339-350. [PMID: 32547682 PMCID: PMC7280866 DOI: 10.4252/wjsc.v12.i5.339] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 01/01/2020] [Revised: 04/07/2020] [Accepted: 04/18/2020] [Indexed: 02/06/2023] Open
Abstract
The postnatal skeleton undergoes growth, modeling, and remodeling. The human skeleton is a composite of diverse tissue types, including bone, cartilage, fat, fibroblasts, nerves, blood vessels, and hematopoietic cells. Fracture nonunion and bone defects are among the most challenging clinical problems in orthopedic trauma. The incidence of nonunion or bone defects following fractures is increasing. Stem and progenitor cells mediate homeostasis and regeneration in postnatal tissue, including bone tissue. As multipotent stem cells, skeletal stem cells (SSCs) have a strong effect on the growth, differentiation, and repair of bone regeneration. In recent years, a number of important studies have characterized the hierarchy, differential potential, and bone formation of SSCs. Here, we describe studies on and applications of SSCs and/or mesenchymal stem cells for bone regeneration.
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Affiliation(s)
- Guo-Ping Xu
- Department of Orthopedics, The Second Affiliated Hospital, Zhejiang University School of Medicine, Hangzhou 310000, Zhejiang Province, China
| | - Xiang-Feng Zhang
- Department of Orthopedics, The Second Affiliated Hospital, Zhejiang University School of Medicine, Hangzhou 310000, Zhejiang Province, China
| | - Lu Sun
- Department of Oral Medicine, Infection and Immunity, Harvard School of Dental Medicine, Harvard University, Boston, MA 02115, United States
| | - Er-Man Chen
- Department of Orthopedics, The Second Affiliated Hospital, Zhejiang University School of Medicine, Hangzhou 310000, Zhejiang Province, China
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35
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Lipid availability determines fate of skeletal progenitor cells via SOX9. Nature 2020; 579:111-117. [PMID: 32103177 PMCID: PMC7060079 DOI: 10.1038/s41586-020-2050-1] [Citation(s) in RCA: 122] [Impact Index Per Article: 30.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/01/2016] [Accepted: 01/08/2020] [Indexed: 12/22/2022]
Abstract
The avascular nature of cartilage makes it a unique tissue1–4, but whether and how the absence of nutrient supply regulates chondrogenesis remains unknown. Here, we show that obstruction of vascular invasion during bone healing favours chondrogenic over osteogenic differentiation of skeletal progenitor cells. Unexpectedly, this process is driven by a decreased availability of extracellular lipids. When lipids are scarce, skeletal progenitors activate FoxO transcription factors, which bind to the Sox9 promoter and increase its expression. Besides initiating chondrogenesis, SOX9 acts as a regulator of cellular metabolism by suppressing fatty acid oxidation, and thus adapts the cells to an avascular life. Our results define lipid scarcity as an important determinant of chondrogenic commitment, reveal a role for FoxOs during lipid starvation, and identify SOX9 as a critical metabolic mediator. These data highlight the importance of the nutritional microenvironment in the specification of skeletal cell fate.
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36
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Moore ER, Chen JC, Jacobs CR. Prx1-Expressing Progenitor Primary Cilia Mediate Bone Formation in response to Mechanical Loading in Mice. Stem Cells Int 2019; 2019:3094154. [PMID: 31814831 PMCID: PMC6877967 DOI: 10.1155/2019/3094154] [Citation(s) in RCA: 16] [Impact Index Per Article: 3.2] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/07/2019] [Revised: 09/14/2019] [Accepted: 09/26/2019] [Indexed: 11/25/2022] Open
Abstract
Increases in mechanical loading can enhance the addition of new bone, altering geometry and density such that bones better withstand higher forces. Bone-forming osteoblasts have long been thought to originate from progenitors, but the exact source is yet to be identified. Previous studies indicate osteogenic precursors arise from Prx1-expressing progenitors during embryonic development and adult fracture repair. However, it is unknown whether this cell population is also a source for mechanically induced active osteoblasts. We first identified that Prx1 is expressed in skeletally mature mouse periosteum, a thin tissue covering the surface of the bone that is rich in osteoprogenitors. We then traced Prx1 progenitor lineage using a transgenic mouse model carrying both a Prx1-driven tamoxifen-inducible Cre and a ROSA-driven lacZ reporter gene. Cells that expressed Prx1 when compressive axial loading was applied were detected within the cortical bone days after stimulation, indicating osteocytes are of Prx1-expressing cell origin. In addition, we evaluated how these cells sense and respond to physical stimulation in vivo by disrupting their primary cilia, which are antenna-like sensory organelles known to enhance mechanical and chemical signaling kinetics. Although Prx1-driven primary cilium disruption did not affect osteoblast recruitment to the bone surface, the relative mineral apposition and bone formation rates were decreased by 53% and 34%, respectively. Thus, this cell population contributes to load-induced bone formation, and primary cilia are needed for a complete response. Interestingly, Prx1-expressing progenitors are easily extracted from periosteum and are perhaps an attractive alternative to marrow stem cells for bone tissue regeneration strategies.
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Affiliation(s)
- Emily R. Moore
- Department of Biomedical Engineering, Columbia University, 500 W 120th Street New York, NY 10027, USA
| | - Julia C. Chen
- Department of Biomedical Engineering, Columbia University, 500 W 120th Street New York, NY 10027, USA
| | - Christopher R. Jacobs
- Department of Biomedical Engineering, Columbia University, 500 W 120th Street New York, NY 10027, USA
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37
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Cabahug-Zuckerman P, Liu C, Cai C, Mahaffey I, Norman SC, Cole W, Castillo AB. Site-Specific Load-Induced Expansion of Sca-1 +Prrx1 + and Sca-1 -Prrx1 + Cells in Adult Mouse Long Bone Is Attenuated With Age. JBMR Plus 2019; 3:e10199. [PMID: 31667455 PMCID: PMC6808224 DOI: 10.1002/jbm4.10199] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 11/15/2018] [Revised: 04/22/2019] [Accepted: 04/23/2019] [Indexed: 02/04/2023] Open
Abstract
Aging is associated with significant bone loss and increased fracture risk, which has been attributed to a diminished response to anabolic mechanical loading. In adults, skeletal progenitors proliferate and differentiate into bone‐forming osteoblasts in response to increasing mechanical stimuli, though the effects of aging on this response are not well‐understood. Here we show that both adult and aged mice exhibit load‐induced periosteal bone formation, though the response is significantly attenuated with age. We also show that the acute response of adult bone to loading involves expansion of Sca‐1+Prrx1+ and Sca‐1−Prrx1+ cells in the periosteum. On the endosteal surface, loading enhances proliferation of both these cell populations, though the response is delayed by 2 days relative to the periosteal surface. In contrast to the periosteum and endosteum, the marrow does not exhibit increased proliferation of Sca‐1+Prrx1+ cells, but only of Sca‐1−Prrx1+ cells, underscoring fundamental differences in how the stem cell niche in distinct bone envelopes respond to mechanical stimuli. Notably, the proliferative response to loading is absent in aged bone even though there are similar baseline numbers of Prrx1 + cells in the periosteum and endosteum, suggesting that the proliferative capacity of progenitors is attenuated with age, and proliferation of the Sca‐1+Prrx1+ population is critical for load‐induced periosteal bone formation. These findings provide a basis for the development of novel therapeutics targeting these cell populations to enhance osteogenesis for overcoming age‐related bone loss. © 2019 The Authors. JBMR Plus published by Wiley Periodicals, Inc. on behalf of American Society for Bone and Mineral Research.
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Affiliation(s)
- Pamela Cabahug-Zuckerman
- Department of Orthopaedic Surgery NYU Langone Health, New York University New York NY USA.,Department of Biomedical Engineering Tandon School of Engineering, New York University New York NY USA.,Rehabilitation Research and Development Veterans Affairs New York Harbor Healthcare System New York NY USA
| | - Chao Liu
- Department of Orthopaedic Surgery NYU Langone Health, New York University New York NY USA.,Department of Biomedical Engineering Tandon School of Engineering, New York University New York NY USA.,Rehabilitation Research and Development Veterans Affairs New York Harbor Healthcare System New York NY USA
| | - Cinyee Cai
- Department of Orthopaedic Surgery NYU Langone Health, New York University New York NY USA.,Department of Biomedical Engineering Tandon School of Engineering, New York University New York NY USA
| | - Ian Mahaffey
- Rehabilitation Research and Development Veterans Affairs Palo Alto Healthcare System Palo Alto CA USA
| | - Stephanie C Norman
- Rehabilitation Research and Development Veterans Affairs Palo Alto Healthcare System Palo Alto CA USA
| | - Whitney Cole
- Rehabilitation Research and Development Veterans Affairs Palo Alto Healthcare System Palo Alto CA USA
| | - Alesha B Castillo
- Department of Orthopaedic Surgery NYU Langone Health, New York University New York NY USA.,Department of Biomedical Engineering Tandon School of Engineering, New York University New York NY USA.,Rehabilitation Research and Development Veterans Affairs New York Harbor Healthcare System New York NY USA
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38
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Bassir SH, Garakani S, Wilk K, Aldawood ZA, Hou J, Yeh SCA, Sfeir C, Lin CP, Intini G. Prx1 Expressing Cells Are Required for Periodontal Regeneration of the Mouse Incisor. Front Physiol 2019; 10:591. [PMID: 31231227 PMCID: PMC6558369 DOI: 10.3389/fphys.2019.00591] [Citation(s) in RCA: 15] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/06/2019] [Accepted: 04/26/2019] [Indexed: 12/12/2022] Open
Abstract
Previous studies have shown that post-natal skeletal stem cells expressing Paired-related homeobox 1 (PRX1 or PRRX1) are present in the periosteum of long bones where they contribute to post-natal bone development and regeneration. Our group also identified post-natal PRX1 expressing cells (pnPRX1+ cells) in mouse calvarial synarthroses (sutures) and showed that these cells are required for calvarial bone regeneration. Since calvarial synarthroses are similar to dentoalveolar gomphosis (periodontium) and since there is no information available on the presence or function of pnPRX1+ cells in the periodontium, the present study aimed at identifying and characterizing pnPRX1+ cells within the mouse periodontium and assess their contribution to periodontal development and regeneration. Here we demonstrated that pnPRX1+ cells are present within the periodontal ligament (PDL) of the mouse molars and of the continuously regenerating mouse incisor. By means of diphtheria toxin (DTA)-mediated conditional ablation of pnPRX1+ cells, we show that pnPRX1+ cells contribute to post-natal periodontal development of the molars and the incisor, as ablation of pnPRX1+ cells in 3-days old mice resulted in a significant enlargement of the PDL space after 18 days. The contribution of pnPRX1+ cells to periodontal regeneration was assessed by developing a novel non-critical size periodontal defect model. Outcomes showed that DTA-mediated post-natal ablation of pnPRX1+ cells results in lack of regeneration in periodontal non-critical size defects in the regeneration competent mouse incisors. Importantly, gene expression analysis of these cells shows a profile typical of quiescent cells, while gene expression analysis of human samples of periodontal stem cells (PDLSC) confirmed that Prx1 is highly expressed in human periodontium. In conclusion, pnPRX1+ cells are present within the continuously regenerating PDL of the mouse incisor, and at such location they contribute to post-natal periodontal development and regeneration. Since this study further reports the presence of PRX1 expressing cells within human periodontal ligament, we suggest that studying the mouse periodontal pnPRX1+ cells may provide significant information for the development of novel and more effective periodontal regenerative therapies in humans.
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Affiliation(s)
- Seyed Hossein Bassir
- Division of Periodontology, Department of Oral Medicine, Infection, and Immunity, Harvard School of Dental Medicine, Boston, MA, United States.,Department of Periodontology, School of Dental Medicine, Stony Brook University, Stony Brook, NY, United States
| | - Sasan Garakani
- Division of Periodontology, Department of Oral Medicine, Infection, and Immunity, Harvard School of Dental Medicine, Boston, MA, United States
| | - Katarzyna Wilk
- Division of Periodontology, Department of Oral Medicine, Infection, and Immunity, Harvard School of Dental Medicine, Boston, MA, United States
| | - Zahra A Aldawood
- Division of Periodontology, Department of Oral Medicine, Infection, and Immunity, Harvard School of Dental Medicine, Boston, MA, United States
| | - Jue Hou
- Advanced Microscopy Program, Center for Systems Biology and Wellman Center for Photomedicine, Massachusetts General Hospital, Harvard Medical School, Boston, MA, United States
| | - Shu-Chi A Yeh
- Division of Periodontology, Department of Oral Medicine, Infection, and Immunity, Harvard School of Dental Medicine, Boston, MA, United States.,Advanced Microscopy Program, Center for Systems Biology and Wellman Center for Photomedicine, Massachusetts General Hospital, Harvard Medical School, Boston, MA, United States
| | - Charles Sfeir
- Department of Periodontics and Preventive Dentistry, University of Pittsburgh School of Dental Medicine, Pittsburgh, PA, United States.,University of Pittsburgh McGowan Institute for Regenerative Medicine, Pittsburgh, PA, United States
| | - Charles P Lin
- Advanced Microscopy Program, Center for Systems Biology and Wellman Center for Photomedicine, Massachusetts General Hospital, Harvard Medical School, Boston, MA, United States.,Harvard Stem Cell Institute, Cambridge, MA, United States
| | - Giuseppe Intini
- Division of Periodontology, Department of Oral Medicine, Infection, and Immunity, Harvard School of Dental Medicine, Boston, MA, United States.,Department of Periodontics and Preventive Dentistry, University of Pittsburgh School of Dental Medicine, Pittsburgh, PA, United States.,University of Pittsburgh McGowan Institute for Regenerative Medicine, Pittsburgh, PA, United States.,Harvard Stem Cell Institute, Cambridge, MA, United States
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39
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Yee CS, Manilay JO, Chang JC, Hum NR, Murugesh DK, Bajwa J, Mendez ME, Economides AE, Horan DJ, Robling AG, Loots GG. Conditional Deletion of Sost in MSC-Derived Lineages Identifies Specific Cell-Type Contributions to Bone Mass and B-Cell Development. J Bone Miner Res 2018; 33:1748-1759. [PMID: 29750826 DOI: 10.1002/jbmr.3467] [Citation(s) in RCA: 30] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 10/10/2017] [Revised: 04/26/2018] [Accepted: 04/28/2018] [Indexed: 11/10/2022]
Abstract
Sclerostin (Sost) is a negative regulator of bone formation and blocking its function via antibodies has shown great therapeutic promise by increasing both bone mass in humans and animal models. Sclerostin deletion in Sost KO mice (Sost-/- ) causes high bone mass (HBM) similar to sclerosteosis patients. Sost-/- mice have been shown to display an up to 300% increase in bone volume/total volume (BV/TV), relative to age-matched controls. It has been postulated that the main source of skeletal sclerostin is the osteocyte. To understand the cell-type specific contributions to the HBM phenotype described in Sost-/- mice, as well as to address the endocrine and paracrine mode of action of sclerostin, we examined the skeletal phenotypes of conditional Sost loss-of-function (SostiCOIN/iCOIN ) mice with specific deletions in (1) the limb mesenchyme (Prx1-Cre; targets osteoprogenitors and their progeny); (2) midstage osteoblasts and their progenitors (Col1-Cre); (3) mature osteocytes (Dmp1-Cre); and (4) hypertrophic chondrocytes and their progenitors (ColX-Cre). All conditional alleles resulted in significant increases in bone mass in trabecular bone in both the femur and lumbar vertebrae, but only Prx1-Cre deletion fully recapitulated the amplitude of the HBM phenotype in the appendicular skeleton and the B-cell defect described in the global KO. Despite WT expression of Sost in the axial skeleton of Prx1-Cre deleted mice, these mice also had a significant increase in bone mass in the vertebrae, but the sclerostin released in circulation by the axial skeleton did not affect bone parameters in the appendicular skeleton. Also, both Col1 and Dmp1 deletion resulted in a similar 80% significant increase in trabecular bone mass, but only Col1 and Prx1 deletion resulted in a significant increase in cortical thickness. We conclude that several cell types within the Prx1-osteoprogenitor-derived lineages contribute significant amounts of sclerostin protein to the paracrine pool of Sost in bone. © 2018 The Authors. Journal of Bone and Mineral Research Published by Wiley Periodicals, Inc.
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Affiliation(s)
- Cristal S Yee
- Physical and Life Sciences Directorate, Lawrence Livermore National Laboratories, Livermore, CA, USA.,Molecular Cell Biology Unit, School of Natural Sciences, University of California-Merced, Merced, CA, USA
| | - Jennifer O Manilay
- Molecular Cell Biology Unit, School of Natural Sciences, University of California-Merced, Merced, CA, USA
| | - Jiun C Chang
- Physical and Life Sciences Directorate, Lawrence Livermore National Laboratories, Livermore, CA, USA.,Molecular Cell Biology Unit, School of Natural Sciences, University of California-Merced, Merced, CA, USA
| | - Nicholas R Hum
- Physical and Life Sciences Directorate, Lawrence Livermore National Laboratories, Livermore, CA, USA
| | - Deepa K Murugesh
- Physical and Life Sciences Directorate, Lawrence Livermore National Laboratories, Livermore, CA, USA
| | - Jamila Bajwa
- Molecular Cell Biology Unit, School of Natural Sciences, University of California-Merced, Merced, CA, USA
| | - Melanie E Mendez
- Physical and Life Sciences Directorate, Lawrence Livermore National Laboratories, Livermore, CA, USA.,Molecular Cell Biology Unit, School of Natural Sciences, University of California-Merced, Merced, CA, USA
| | | | - Daniel J Horan
- Department of Anatomy and Cell Biology, Indiana University School of Medicine, Indianapolis, IN, USA
| | - Alexander G Robling
- Department of Anatomy and Cell Biology, Indiana University School of Medicine, Indianapolis, IN, USA
| | - Gabriela G Loots
- Physical and Life Sciences Directorate, Lawrence Livermore National Laboratories, Livermore, CA, USA.,Molecular Cell Biology Unit, School of Natural Sciences, University of California-Merced, Merced, CA, USA
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40
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Guo YC, Wang MY, Zhang SW, Wu YS, Zhou CC, Zheng RX, Shao B, Wang Y, Xie L, Liu WQ, Sun NY, Jing JJ, Ye L, Chen QM, Yuan Q. Ubiquitin-specific protease USP34 controls osteogenic differentiation and bone formation by regulating BMP2 signaling. EMBO J 2018; 37:embj.201899398. [PMID: 30181118 DOI: 10.15252/embj.201899398] [Citation(s) in RCA: 50] [Impact Index Per Article: 8.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/07/2018] [Revised: 07/30/2018] [Accepted: 08/13/2018] [Indexed: 02/05/2023] Open
Abstract
The osteogenic differentiation of mesenchymal stem cells (MSCs) is governed by multiple mechanisms. Growing evidence indicates that ubiquitin-dependent protein degradation is critical for the differentiation of MSCs and bone formation; however, the function of ubiquitin-specific proteases, the largest subfamily of deubiquitylases, remains unclear. Here, we identify USP34 as a previously unknown regulator of osteogenesis. The expression of USP34 in human MSCs increases after osteogenic induction while depletion of USP34 inhibits osteogenic differentiation. Conditional knockout of Usp34 from MSCs or pre-osteoblasts leads to low bone mass in mice. Deletion of Usp34 also blunts BMP2-induced responses and impairs bone regeneration. Mechanically, we demonstrate that USP34 stabilizes both Smad1 and RUNX2 and that depletion of Smurf1 restores the osteogenic potential of Usp34-deficient MSCs in vitro Taken together, our data indicate that USP34 is required for osteogenic differentiation and bone formation.
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Affiliation(s)
- Yu-Chen Guo
- State Key Laboratory of Oral Diseases, National Clinical Research Center for Oral Diseases, West China Hospital of Stomatology, Sichuan University, Chengdu, China
| | - Meng-Yuan Wang
- State Key Laboratory of Oral Diseases, National Clinical Research Center for Oral Diseases, West China Hospital of Stomatology, Sichuan University, Chengdu, China
| | - Shi-Wen Zhang
- State Key Laboratory of Oral Diseases, National Clinical Research Center for Oral Diseases, West China Hospital of Stomatology, Sichuan University, Chengdu, China
| | - Yun-Shu Wu
- State Key Laboratory of Oral Diseases, National Clinical Research Center for Oral Diseases, West China Hospital of Stomatology, Sichuan University, Chengdu, China
| | - Chen-Chen Zhou
- State Key Laboratory of Oral Diseases, National Clinical Research Center for Oral Diseases, West China Hospital of Stomatology, Sichuan University, Chengdu, China
| | - Ri-Xin Zheng
- State Key Laboratory of Oral Diseases, National Clinical Research Center for Oral Diseases, West China Hospital of Stomatology, Sichuan University, Chengdu, China
| | - Bin Shao
- State Key Laboratory of Oral Diseases, National Clinical Research Center for Oral Diseases, West China Hospital of Stomatology, Sichuan University, Chengdu, China
| | - Yuan Wang
- State Key Laboratory of Oral Diseases, National Clinical Research Center for Oral Diseases, West China Hospital of Stomatology, Sichuan University, Chengdu, China
| | - Liang Xie
- State Key Laboratory of Oral Diseases, National Clinical Research Center for Oral Diseases, West China Hospital of Stomatology, Sichuan University, Chengdu, China
| | - Wei-Qing Liu
- State Key Laboratory of Oral Diseases, National Clinical Research Center for Oral Diseases, West China Hospital of Stomatology, Sichuan University, Chengdu, China
| | - Ning-Yuan Sun
- State Key Laboratory of Oral Diseases, National Clinical Research Center for Oral Diseases, West China Hospital of Stomatology, Sichuan University, Chengdu, China
| | - Jun-Jun Jing
- State Key Laboratory of Oral Diseases, National Clinical Research Center for Oral Diseases, West China Hospital of Stomatology, Sichuan University, Chengdu, China
| | - Ling Ye
- State Key Laboratory of Oral Diseases, National Clinical Research Center for Oral Diseases, West China Hospital of Stomatology, Sichuan University, Chengdu, China
| | - Qian-Ming Chen
- State Key Laboratory of Oral Diseases, National Clinical Research Center for Oral Diseases, West China Hospital of Stomatology, Sichuan University, Chengdu, China
| | - Quan Yuan
- State Key Laboratory of Oral Diseases, National Clinical Research Center for Oral Diseases, West China Hospital of Stomatology, Sichuan University, Chengdu, China
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41
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Moore ER, Yang Y, Jacobs CR. Primary cilia are necessary for Prx1-expressing cells to contribute to postnatal skeletogenesis. J Cell Sci 2018; 131:jcs.217828. [PMID: 30002136 DOI: 10.1242/jcs.217828] [Citation(s) in RCA: 20] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/14/2018] [Accepted: 07/06/2018] [Indexed: 12/30/2022] Open
Abstract
Although Prx1 (also known as PRRX1)-expressing cells and their primary cilia are critical for embryonic development, they have yet to be studied in the context of postnatal skeletogenesis owing to the lethality of mouse models. A tamoxifen-inducible Prx1 model has been developed, and we determined that expression directed by this promoter is highly restricted to the cambium layers in the periosteum and perichondrium after birth. To determine the postnatal role of these cambium layer osteochondroprogenitors (CLOPs) and their primary cilia, we developed models to track the fate of CLOPs (Prx1CreER-GFP;Rosa26tdTomato) and selectively disrupt their cilia (Prx1CreER-GFP;Ift88fl/fl). Our tracking studies revealed that CLOPs populate cortical and trabecular bone, the growth plate and secondary ossification centers during the normal program of postnatal skeletogenesis. Furthermore, animals lacking CLOP cilia exhibit stunted limb growth due to disruptions in endochondral and intramembranous ossification. Histological examination indicates that growth is stunted due to limited differentiation, proliferation and/or abnormal hypertrophic differentiation in the growth plate. Collectively, our results suggest that CLOPs are programmed to rapidly populate distant tissues and produce bone via a primary cilium-mediated mechanism in the postnatal skeleton.
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Affiliation(s)
- Emily R Moore
- Department of Biomedical Engineering, Columbia University, 500 W 120th St, New York, NY 10027, USA
| | - Yuchen Yang
- Department of Biomedical Engineering, Columbia University, 500 W 120th St, New York, NY 10027, USA
| | - Christopher R Jacobs
- Department of Biomedical Engineering, Columbia University, 500 W 120th St, New York, NY 10027, USA
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Abstract
PURPOSE OF REVIEW The identity and functional roles of stem cell population(s) that contribute to fracture repair remains unclear. This review provides a brief history of mesenchymal stem cell (MSCs) and provides an updated view of the many stem/progenitor cell populations contributing to fracture repair. RECENT FINDINGS Functional studies show MSCs are not the multipotential stem cell population that form cartilage and bone during fracture repair. Rather, multiple studies have confirmed the periosteum is the primary source of stem/progenitor cells for fracture repair. Newer work is also identifying other stem/progenitor cells that may also contribute to healing. Although the heterogenous periosteal cells migrate to the fracture site and contribute directly to callus formation, other cell populations are involved. Pericytes and bone marrow stromal cells are now thought of as key secretory centers that mostly coordinate the repair process. Other populations of stem/progenitor cells from the muscle and transdifferentiated chondroctyes may also contribute to repair, and their functional role is an area of active research.
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Affiliation(s)
- Beth C Bragdon
- Department of Orthopaedic Surgery, Boston University School of Medicine, 72 East Concord St, Evans 243, Boston, MA, 02118, USA.
| | - Chelsea S Bahney
- Orthopaedic Trauma Institute, Department of Orthopaedic Surgery, University of California, San Francisco (UCSF), San Francisco, CA, USA
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Moore ER, Zhu YX, Ryu HS, Jacobs CR. Periosteal progenitors contribute to load-induced bone formation in adult mice and require primary cilia to sense mechanical stimulation. Stem Cell Res Ther 2018; 9:190. [PMID: 29996901 PMCID: PMC6042447 DOI: 10.1186/s13287-018-0930-1] [Citation(s) in RCA: 39] [Impact Index Per Article: 6.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/09/2018] [Revised: 06/11/2018] [Accepted: 06/14/2018] [Indexed: 02/07/2023] Open
Abstract
BACKGROUND The fully developed adult skeleton adapts to mechanical forces by generating more bone, usually at the periosteal surface. Progenitor cells in the periosteum are believed to differentiate into bone-forming osteoblasts that contribute to load-induced adult bone formation, but in vivo evidence does not yet exist. Furthermore, the mechanism by which periosteal progenitors might sense physical loading and trigger differentiation is unknown. We propose that periosteal osteochondroprogenitors (OCPs) directly sense mechanical load and differentiate into bone-forming osteoblasts via their primary cilia, mechanosensory organelles known to be involved in osteogenic differentiation. METHODS We generated a diphtheria toxin ablation mouse model and performed ulnar loading and dynamic histomorphometry to quantify the contribution of periosteal OCPs in adult bone formation in vivo. We also generated a primary cilium knockout model and isolated periosteal cells to study the role of the cilium in periosteal OCP mechanosensing in vitro. Experimental groups were compared using one-way analysis of variance or student's t test, and sample size was determined to achieve a minimum power of 80%. RESULTS Mice without periosteal OCPs had severely attenuated mechanically induced bone formation and lacked the mineralization necessary for daily skeletal maintenance. Our in vitro results demonstrate that OCPs in the periosteum uniquely sense fluid shear and exhibit changes in osteogenic markers consistent with osteoblast differentiation; however, this response is essentially lost when the primary cilium is absent. CONCLUSIONS Combined, our data show that periosteal progenitors are a mechanosensitive cell source that significantly contribute to adult skeletal maintenance. More importantly, an OCP population persists in the adult skeleton and these cells, as well as their cilia, are promising targets for bone regeneration strategies.
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Affiliation(s)
- Emily R. Moore
- Columbia University Department of Biomedical Engineering, 500 W 120th St, New York, NY 10027 USA
| | - Ya Xing Zhu
- Columbia University Department of Biomedical Engineering, 500 W 120th St, New York, NY 10027 USA
| | - Han Seul Ryu
- Columbia University Department of Biomedical Engineering, 500 W 120th St, New York, NY 10027 USA
| | - Christopher R. Jacobs
- Columbia University Department of Biomedical Engineering, 500 W 120th St, New York, NY 10027 USA
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44
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Yeh SCA, Wilk K, Lin CP, Intini G. In Vivo 3D Histomorphometry Quantifies Bone Apposition and Skeletal Progenitor Cell Differentiation. Sci Rep 2018; 8:5580. [PMID: 29615817 PMCID: PMC5882859 DOI: 10.1038/s41598-018-23785-6] [Citation(s) in RCA: 10] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/28/2017] [Accepted: 03/20/2018] [Indexed: 01/07/2023] Open
Abstract
Histomorphometry and Micro-CT are commonly used to assess bone remodeling and bone microarchitecture. These approaches typically require separate cohorts of animals to analyze 3D morphological changes and involve time-consuming immunohistochemistry preparation. Intravital Microscopy (IVM) in combination with mouse genetics may represent an attractive option to obtain bone architectural measurements while performing longitudinal monitoring of dynamic cellular processes in vivo. In this study we utilized two-photon, multicolor fluorescence IVM together with a lineage tracing reporter mouse model to image skeletal stem cells (SSCs) in their calvarial suture niche and analyze their differentiation fate after stimulation with an agonist of the canonical Wnt pathway (recombinant Wnt3a). Our in vivo histomorphometry analyses of bone formation, suture volume, and cellular dynamics showed that recombinant Wnt3a induces new bone formation, differentiation and incorporation of SSCs progeny into newly forming bone. IVM technology can therefore provide additional dynamic 3D information to the traditional static 2D histomorphometry.
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Affiliation(s)
- Shu-Chi A Yeh
- Department of Oral Medicine, Infection, and Immunity, Harvard School of Dental Medicine, Boston, MA, 02115, USA.,Advanced Microscopy Program, Center for Systems Biology and Wellman Center for Photomedicine, Massachusetts General Hospital, Harvard Medical School, Boston, MA, 02114, USA
| | - Katarzyna Wilk
- Department of Oral Medicine, Infection, and Immunity, Harvard School of Dental Medicine, Boston, MA, 02115, USA
| | - Charles P Lin
- Advanced Microscopy Program, Center for Systems Biology and Wellman Center for Photomedicine, Massachusetts General Hospital, Harvard Medical School, Boston, MA, 02114, USA. .,Harvard Stem Cell Institute, Cambridge, MA, 02138, USA.
| | - Giuseppe Intini
- Department of Oral Medicine, Infection, and Immunity, Harvard School of Dental Medicine, Boston, MA, 02115, USA. .,Harvard Stem Cell Institute, Cambridge, MA, 02138, USA.
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45
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Yang CY, Jeon HH, Alshabab A, Lee YJ, Chung CH, Graves DT. RANKL deletion in periodontal ligament and bone lining cells blocks orthodontic tooth movement. Int J Oral Sci 2018; 10:3. [PMID: 29483595 PMCID: PMC5944595 DOI: 10.1038/s41368-017-0004-8] [Citation(s) in RCA: 50] [Impact Index Per Article: 8.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/13/2017] [Revised: 08/22/2017] [Accepted: 10/04/2017] [Indexed: 11/09/2022] Open
Abstract
The bone remodeling process in response to orthodontic forces requires the activity of osteoclasts to allow teeth to move in the direction of the force applied. Receptor activator of nuclear factor-κB ligand (RANKL) is essential for this process although its cellular source in response to orthodontic forces has not been determined. Orthodontic tooth movement is considered to be an aseptic inflammatory process that is stimulated by leukocytes including T and B lymphocytes which are presumed to stimulate bone resorption. We determined whether periodontal ligament and bone lining cells were an essential source of RANKL by tamoxifen induced deletion of RANKL in which Cre recombinase was driven by a 3.2 kb reporter element of the Col1α1 gene in experimental mice (Col1α1.CreERTM+.RANKLf/f) and compared results with littermate controls (Col1α1.CreERTM-.RANKLf/f). By examination of Col1α1.CreERTM+.ROSA26 reporter mice we showed tissue specificity of tamoxifen induced Cre recombinase predominantly in the periodontal ligament and bone lining cells. Surprisingly we found that most of the orthodontic tooth movement and formation of osteoclasts was blocked in the experimental mice, which also had a reduced periodontal ligament space. Thus, we demonstrate for the first time that RANKL produced by periodontal ligament and bone lining cells provide the major driving force for tooth movement and osteoclastogenesis in response to orthodontic forces.
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Affiliation(s)
- Chia-Ying Yang
- Department of Orthodontics, School of Dental Medicine, University of Pennsylvania, Philadelphia, PA, USA
- Department of Periodontics, School of Dental Medicine, University of Pennsylvania, Philadelphia, PA, USA
| | - Hyeran Helen Jeon
- Department of Orthodontics, School of Dental Medicine, University of Pennsylvania, Philadelphia, PA, USA
- Department of Periodontics, School of Dental Medicine, University of Pennsylvania, Philadelphia, PA, USA
| | - Ahmed Alshabab
- Department of Periodontics, School of Dental Medicine, University of Pennsylvania, Philadelphia, PA, USA
| | - Yu Jin Lee
- Department of Periodontics, School of Dental Medicine, University of Pennsylvania, Philadelphia, PA, USA
| | - Chun-Hsi Chung
- Department of Orthodontics, School of Dental Medicine, University of Pennsylvania, Philadelphia, PA, USA
| | - Dana T Graves
- Department of Periodontics, School of Dental Medicine, University of Pennsylvania, Philadelphia, PA, USA.
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46
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Stiers PJ, van Gastel N, Moermans K, Stockmans I, Carmeliet G. An Ectopic Imaging Window for Intravital Imaging of Engineered Bone Tissue. JBMR Plus 2018; 2:92-102. [PMID: 30283894 PMCID: PMC6124161 DOI: 10.1002/jbm4.10028] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 07/11/2017] [Revised: 12/11/2017] [Accepted: 12/12/2017] [Indexed: 01/16/2023] Open
Abstract
Tissue engineering is a promising branch of regenerative medicine, but its clinical application remains limited because thorough knowledge of the in vivo repair processes in these engineered implants is limited. Common techniques to study the different phases of bone repair in mice are destructive and thus not optimal to gain insight into the dynamics of this process. Instead, multiphoton‐intravital microscopy (MP‐IVM) allows visualization of (sub)cellular processes at high resolution and frequency over extended periods of time when combined with an imaging window that permits optical access to implants in vivo. In this study, we have developed and validated an ectopic imaging window that can be placed over a tissue‐engineered construct implanted in mice. This approach did not interfere with the biological processes of bone regeneration taking place in these implants, as evidenced by histological and micro–computed tomography (μCT)‐based comparison to control ectopic implants. The ectopic imaging window permitted tracking of individual cells over several days in vivo. Furthermore, the use of fluorescent reporters allowed visualization of the onset of angiogenesis and osteogenesis in these constructs. Taken together, this novel imaging window will facilitate further analysis of the spatiotemporal regulation of cellular processes in bone tissue–engineered implants and provides a powerful tool to enhance the therapeutic potential of bone tissue engineering. © 2017 The Authors JBMR Plus published by Wiley Periodicals, Inc. on behalf of American Society for Bone and Mineral Research.
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Affiliation(s)
- Pieter-Jan Stiers
- Laboratory of Clinical and Experimental Endocrinology Department of Chronic Diseases, Metabolism and Ageing KU Leuven Leuven Belgium.,Prometheus Division of Skeletal Tissue Engineering KU Leuven Leuven Belgium
| | - Nick van Gastel
- Laboratory of Clinical and Experimental Endocrinology Department of Chronic Diseases, Metabolism and Ageing KU Leuven Leuven Belgium.,Prometheus Division of Skeletal Tissue Engineering KU Leuven Leuven Belgium
| | - Karen Moermans
- Laboratory of Clinical and Experimental Endocrinology Department of Chronic Diseases, Metabolism and Ageing KU Leuven Leuven Belgium
| | - Ingrid Stockmans
- Laboratory of Clinical and Experimental Endocrinology Department of Chronic Diseases, Metabolism and Ageing KU Leuven Leuven Belgium
| | - Geert Carmeliet
- Laboratory of Clinical and Experimental Endocrinology Department of Chronic Diseases, Metabolism and Ageing KU Leuven Leuven Belgium.,Prometheus Division of Skeletal Tissue Engineering KU Leuven Leuven Belgium
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47
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Comparative analysis of gene expression identifies distinct molecular signatures of bone marrow- and periosteal-skeletal stem/progenitor cells. PLoS One 2018; 13:e0190909. [PMID: 29342188 PMCID: PMC5771600 DOI: 10.1371/journal.pone.0190909] [Citation(s) in RCA: 14] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/02/2017] [Accepted: 12/21/2017] [Indexed: 12/22/2022] Open
Abstract
Periosteum and bone marrow (BM) both contain skeletal stem/progenitor cells (SSCs) that participate in fracture repair. However, the functional difference and selective regulatory mechanisms of SSCs in different locations are unknown due to the lack of specific markers. Here, we report a comprehensive gene expression analysis of bone marrow SSCs (BM-SSCs), periosteal SSCs (P-SSCs), and more differentiated osteoprogenitors by using reporter mice expressing Interferon-inducible Mx1 and NestinGFP, previously known SSC markers. We first defined that the BM-SSCs can be enriched by the combination of Mx1 and NestinGFP expression, while endogenous P-SSCs can be isolated by positive selection of Mx1, CD105 and CD140a (known SSC markers) combined with the negative selection of CD45, CD31, and osteocalcinGFP (a mature osteoblast marker). Comparative gene expression analysis with FACS-sorted BM-SSCs, P-SSCs, Osterix+ preosteoblasts, CD51+ stroma cells and CD45+ hematopoietic cells as controls revealed that BM-SSCs and P-SSCs have high similarity with few potential differences without statistical significance. We also found that CD51+ cells are highly heterogeneous and have little overlap with SSCs. This was further supported by the microarray cluster analysis, where the two SSC populations clustered together but are separate from the CD51+ cells. However, when comparing SSC population to controls, we found several genes that are uniquely upregulated in endogenous SSCs. Amongst these genes, we found KDR (aka Flk1 or VEGFR2) to be most interesting and discovered that it is highly and selectively expressed in P-SSCs. This finding suggests that endogenous P-SSCs are functionally very similar to BM-SSCs with undetectable significant differences in gene expression but there are distinct molecular signatures in P-SSCs, which can be useful to specify P-SSC subset in vivo.
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48
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Stiers PJ, van Gastel N, Moermans K, Stockmans I, Carmeliet G. Regulatory elements driving the expression of skeletal lineage reporters differ during bone development and adulthood. Bone 2017; 105:154-162. [PMID: 28863946 DOI: 10.1016/j.bone.2017.08.029] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 06/09/2017] [Revised: 08/28/2017] [Accepted: 08/28/2017] [Indexed: 01/06/2023]
Abstract
To improve bone healing or regeneration more insight in the fate and role of the different skeletal cell types is required. Mouse models for fate mapping and lineage tracing of skeletal cells, using stage-specific promoters, have advanced our understanding of bone development, a process that is largely recapitulated during bone repair. However, validation of these models is often only performed during development, whereas proof of the activity and specificity of the used promoters during the bone regenerative process is limited. Here, we show that the regulatory elements of the 6kb collagen type II promoter are not adequate to drive gene expression during bone repair. Similarly, the 2.3kb promoter of collagen type I lacks activity in adult mice, but the 3.2kb promoter is suitable. Furthermore, Cre-mediated fate mapping allows the visualization of progeny, but this label retention may hinder to distinguish these cells from ones with active expression of the marker at later time points. Together, our results show that the lineage-specific regulatory elements driving gene expression during bone development differ from those required later in life and during bone repair, and justify validation of lineage-specific cell tracing and gene silencing strategies during fracture healing and bone regenerative applications.
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Affiliation(s)
- Pieter-Jan Stiers
- Laboratory of Clinical and Experimental Endocrinology, Department of Clinical and Experimental Medicine, KU Leuven, Leuven, Belgium; Prometheus, Division of Skeletal Tissue Engineering, KU Leuven, Leuven, Belgium
| | - Nick van Gastel
- Laboratory of Clinical and Experimental Endocrinology, Department of Clinical and Experimental Medicine, KU Leuven, Leuven, Belgium; Prometheus, Division of Skeletal Tissue Engineering, KU Leuven, Leuven, Belgium
| | - Karen Moermans
- Laboratory of Clinical and Experimental Endocrinology, Department of Clinical and Experimental Medicine, KU Leuven, Leuven, Belgium
| | - Ingrid Stockmans
- Laboratory of Clinical and Experimental Endocrinology, Department of Clinical and Experimental Medicine, KU Leuven, Leuven, Belgium
| | - Geert Carmeliet
- Laboratory of Clinical and Experimental Endocrinology, Department of Clinical and Experimental Medicine, KU Leuven, Leuven, Belgium; Prometheus, Division of Skeletal Tissue Engineering, KU Leuven, Leuven, Belgium.
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49
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Doro DH, Grigoriadis AE, Liu KJ. Calvarial Suture-Derived Stem Cells and Their Contribution to Cranial Bone Repair. Front Physiol 2017; 8:956. [PMID: 29230181 PMCID: PMC5712071 DOI: 10.3389/fphys.2017.00956] [Citation(s) in RCA: 49] [Impact Index Per Article: 7.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/29/2017] [Accepted: 11/10/2017] [Indexed: 12/13/2022] Open
Abstract
In addition to the natural turnover during life, the bones in the skeleton possess the ability to self-repair in response to injury or disease-related bone loss. Based on studies of bone defect models, both processes are largely supported by resident stem cells. In the long bones, the source of skeletal stem cells has been widely investigated over the years, where the major stem cell population is thought to reside in the perivascular niche of the bone marrow. In contrast, we have very limited knowledge about the stem cells contributing to the repair of calvarial bones. In fact, until recently, the presence of specific stem cells in adult craniofacial bones was uncertain. These flat bones are mainly formed via intramembranous rather than endochondral ossification and thus contain minimal bone marrow space. It has been previously proposed that the overlying periosteum and underlying dura mater provide osteoprogenitors for calvarial bone repair. Nonetheless, recent studies have identified a major stem cell population within the suture mesenchyme with multiple differentiation abilities and intrinsic reparative potential. Here we provide an updated review of calvarial stem cells and potential mechanisms of regulation in the context of skull injury repair.
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Affiliation(s)
- Daniel H Doro
- Centre for Craniofacial and Regenerative Biology, King's College London, Guy's Hospital, London, United Kingdom
| | - Agamemnon E Grigoriadis
- Centre for Craniofacial and Regenerative Biology, King's College London, Guy's Hospital, London, United Kingdom
| | - Karen J Liu
- Centre for Craniofacial and Regenerative Biology, King's College London, Guy's Hospital, London, United Kingdom
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50
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Fierro FA, Nolta JA, Adamopoulos IE. Concise Review: Stem Cells in Osteoimmunology. Stem Cells 2017; 35:1461-1467. [PMID: 28390147 DOI: 10.1002/stem.2625] [Citation(s) in RCA: 32] [Impact Index Per Article: 4.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/07/2016] [Revised: 02/06/2017] [Accepted: 03/16/2017] [Indexed: 12/11/2022]
Abstract
Bone remodeling is a lifelong process in which mature bone tissue is removed from the skeleton by bone resorption and is replenished by new during ossification or bone formation. The remodeling cycle requires both the differentiation and activation of two cell types with opposing functions; the osteoclast, which orchestrates bone resorption, and the osteoblast, which orchestrates bone formation. The differentiation of these cells from their respective precursors is a process which has been overshadowed by enigma, particularly because the precise osteoclast precursor has not been identified and because the identification of skeletal stem cells, which give rise to osteoblasts, is very recent. Latest advances in the area of stem cell biology have enabled us to gain a better understanding of how these differentiation processes occur in physiological and pathological conditions. In this review we postulate that modulation of stem cells during inflammatory conditions is a necessary prerequisite of bone remodeling and therefore an essential new component to the field of osteoimmunology. In this context, we highlight the role of transcription factor nuclear factor of activated T cells cytoplasmic 1 (NFATc1), because it directly links inflammation with differentiation of osteoclasts and osteoblasts. Stem Cells 2017;35:1461-1467.
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Affiliation(s)
- Fernando A Fierro
- Stem Cell Program, University of California at Davis, Sacramento, California, USA.,Department of Cell Biology and Human Anatomy, University of California at Davis, Sacramento, California, USA
| | - Jan A Nolta
- Stem Cell Program, University of California at Davis, Sacramento, California, USA.,Department of Cell Biology and Human Anatomy, University of California at Davis, Sacramento, California, USA.,Department of Internal Medicine, University of California at Davis, Sacramento, California, USA
| | - Iannis E Adamopoulos
- Institute for Pediatric Regenerative Medicine, University of California at Davis, Sacramento, California, USA.,Department of Rheumatology, University of California at Davis, Sacramento, California, USA
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