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Jiang X, Zeng F, Zhang L, Yu A, Lu A. Engineered Injectable Cell-Laden Chitin/Chitosan Hydrogel with Adhesion and Biodegradability for Calvarial Defect Regeneration. ACS APPLIED MATERIALS & INTERFACES 2023; 15:20761-20773. [PMID: 37075321 DOI: 10.1021/acsami.3c02108] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/03/2023]
Abstract
Trade-off of high-strength and dynamic crosslinking of hydrogels remains an enormous challenge. Motivated by the self-healing property of biological tissues, the strategy of combining multiple dynamic bond mechanisms and a polysaccharide network is proposed to fabricate biomimetic hydrogels with sufficient mechanical strength, injectability, biodegradability, and self-healing property for bone reconstruction engineering. Stable acylhydrazone bonds endowed hydrogels with robust mechanical strength (>10 kPa). The integration of dynamic imine bonds and acylhydrazone bonds optimized the reversible characteristic to protect the cell during the injection and mimicked ECM microenvironment for cell differentiation as well as rapid adapting bone defect area. Furthermore, due to the slow enzymatic hydrolysis kinetics of chitosan and the self-healing properties of resulting networks, hydrogels exhibited a satisfactory biodegradation period (>8 weeks) that highly matches with bone regeneration. Additionally, rBMSC-laden hydrogels exhibited splendid osteogenic induction and bone reconstruction without prefabrication scaffolds and incubation, demonstrating tremendous potential for clinical application. This work proposes an efficient strategy for the construction of a low-cost multifunctional hydrogel, making polysaccharide-based hydrogels as the optimal carrier for enabling cellular functions in bone repair.
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Affiliation(s)
- Xueyu Jiang
- College of Chemistry and Molecular Sciences, Hubei Engineering Center of Natural Polymer-based Medical Materials, Wuhan University, Wuhan 430072, China
- College of Food Science and Engineering/Hubei Key Laboratory for Processing and Transformation of Agricultural Products, Wuhan Polytechnic University, Wuhan 430023, China
| | - Fanwei Zeng
- Department of Orthopedics Trauma and Microsurgery, Zhongnan Hospital of Wuhan University, Wuhan 430071, China
| | - Lina Zhang
- College of Chemistry and Molecular Sciences, Hubei Engineering Center of Natural Polymer-based Medical Materials, Wuhan University, Wuhan 430072, China
| | - Aixi Yu
- Department of Orthopedics Trauma and Microsurgery, Zhongnan Hospital of Wuhan University, Wuhan 430071, China
| | - Ang Lu
- College of Chemistry and Molecular Sciences, Hubei Engineering Center of Natural Polymer-based Medical Materials, Wuhan University, Wuhan 430072, China
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Lu H, Xiao L, Wang W, Li X, Ma Y, Zhang Y, Wang X. Fibrinolysis Regulation: A Promising Approach to Promote Osteogenesis. TISSUE ENGINEERING. PART B, REVIEWS 2022; 28:1192-1208. [PMID: 35442086 DOI: 10.1089/ten.teb.2021.0222] [Citation(s) in RCA: 2] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 12/14/2022]
Abstract
Soon after bone fracture, the initiation of the coagulation cascade results in the formation of a blood clot, which acts as a natural material to facilitate cell migration and osteogenic differentiation at the fracture site. The existence of hematoma is important in early stage of bone healing, but the persistence of hematoma is considered harmful for bone regeneration. Fibrinolysis is recently regarded as a period of critical transition in angiogenic-osteogenic coupling, it thereby is vital for the complete healing of the bone. Moreover, the enhanced fibrinolysis is proposed to boost bone regeneration through promoting the formation of blood vessels, and fibrinolysis system as well as the products of fibrinolysis also play crucial roles in the bone healing process. Therefore, the purpose of this review is to elucidate the fibrinolysis-derived effects on osteogenesis and summarize the potential approaches-improving bone healing by regulating fibrinolysis, with the purpose to further understand the integral roles of fibrinolysis in bone regeneration and to provide theoretical knowledge for potential fibrinolysis-related osteogenesis strategies. Impact statement Fibrinolysis emerging as a new and viable therapeutic intervention to be contained within osteogenesis strategies, however to now, there have been no review articles which collates the information between fibrinolysis and osteogenesis. This review, therefore, focusses on the effects that fibrinolysis exerts on bone healing, with a purpose to provide theoretical reference to develop new strategies to modulate fibrinolysis to accelerate fibrinolysis thus enhancing bone healing.
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Affiliation(s)
- Haiping Lu
- Department of Orthopaedic Surgery, Affiliated Hospital of Zunyi Medical University, Zunyi, Guizhou, China
| | - Lan Xiao
- School of Mechanical, Medical and Process Engineering, Center for Biomedical Technologies, Queensland University of Technology, Brisbane, Queensland, Australia.,The Australia-China Center for Tissue Engineering and Regenerative Medicine, Kelvin Grove, Brisbane, Queensland, Australia
| | - Weiqun Wang
- Department of Orthopaedic Surgery, Affiliated Hospital of Zunyi Medical University, Zunyi, Guizhou, China
| | - Xuyan Li
- Department of Orthopaedic Surgery, Affiliated Hospital of Zunyi Medical University, Zunyi, Guizhou, China
| | - Yaping Ma
- Department of Orthopaedic Surgery, Affiliated Hospital of Zunyi Medical University, Zunyi, Guizhou, China
| | - Yi Zhang
- Department of Hygiene Toxicology, School of Public Health, Zunyi Medical University, Zunyi, Guizhou, China
| | - Xin Wang
- Department of Orthopaedic Surgery, Affiliated Hospital of Zunyi Medical University, Zunyi, Guizhou, China.,School of Mechanical, Medical and Process Engineering, Center for Biomedical Technologies, Queensland University of Technology, Brisbane, Queensland, Australia.,The Australia-China Center for Tissue Engineering and Regenerative Medicine, Kelvin Grove, Brisbane, Queensland, Australia
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Enhancement of Immunosuppressive Activity of Mesenchymal Stromal Cells by Platelet-Derived Factors is Accompanied by Apoptotic Priming. Stem Cell Rev Rep 2022; 19:713-733. [PMID: 36417151 PMCID: PMC10070232 DOI: 10.1007/s12015-022-10471-4] [Citation(s) in RCA: 2] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Accepted: 10/19/2022] [Indexed: 11/24/2022]
Abstract
Abstract
The pro-inflammatory phase of bone healing, initiated by platelet activation and eventually hematoma formation, impacts bone marrow mesenchymal stromal cells (MSCs) in unknown ways. Here, we created platelet-rich plasma (PRP) hydrogels to study how platelet-derived factors modulate functional properties of encapsulated MSCs in comparison to a non-inflammatory fibrin (FBR) hydrogel environment. MSCs were isolated from human bone marrow, while PRP was collected from pooled apheresis thrombocyte concentrates and used for hydrogel preparation. After their encapsulation in hydrogels for 72 h, retrieved MSCs were analyzed for immunomodulatory activities, apoptosis, stem cell properties, senescence, CD9+, CD63+ and CD81+ extracellular vesicle (EV) release, and metabolism-related changes. PRP-hydrogels stimulated immunosuppressive functions of MSCs, along with their upregulated susceptibility to cell death in communication with PBMCs and augmented caspase 3/7 activity. We found impaired clonal growth and cell cycle progression, and more pronounced β-galactosidase activity as well as accumulation of LC3-II-positive vacuoles in PRP-MSCs. Stimuli derived from PRP-hydrogels upregulated AKT and reduced mTOR phosphorylation in MSCs, which suggests an initiation of survival-related processes. Our results showed that PRP-hydrogels might represent a metabolically stressful environment, inducing acidification of MSCs, reducing polarization of the mitochondrial membrane and increasing lipid accumulation. These features were not detected in FBR-MSCs, which showed reduced CD63+ and CD81+ EV production and maintained clonogenicity. Our data revealed that PRP-derived hematoma components cause metabolic adaptation of MSCs followed by increased immune regulatory functions. For the first time, we showed that PRP stimuli represent a survival challenge and “apoptotic priming” that are detrimental for stem cell-like growth of MSCs and important for their therapeutic consideration.
Graphical Abstract
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Zhu Y, Zhao S, Cheng L, Lin Z, Zeng M, Ruan Z, Sun B, Luo Z, Tang Y, Long H. Mg 2+ -mediated autophagy-dependent polarization of macrophages mediates the osteogenesis of bone marrow stromal stem cells by interfering with macrophage-derived exosomes containing miR-381. J Orthop Res 2022; 40:1563-1576. [PMID: 34727384 DOI: 10.1002/jor.25189] [Citation(s) in RCA: 16] [Impact Index Per Article: 8.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 04/30/2021] [Revised: 09/02/2021] [Accepted: 09/30/2021] [Indexed: 02/04/2023]
Abstract
Magnesium ion (Mg2+ ) has received increased attention due to the roles it plays in promoting osteogenesis and preventing inflammation. This study was designed to investigate the mechanism by which Mg2+ influences the osteoblastic differentiation of bone marrow stromal stem cells (BMSCs). The polarization of Mø (macrophages) was measured after treatment with Mg2+ . Meanwhile, autophagy in Mø was measured by detecting LC3B expression. Mø-derived exosomes were isolated and cocultured with BMSCs; after which, osteogenic differentiation was evaluated by Alizarin Red staining and detection of alkaline phosphatase (ALP). Our results showed that Mg2+ could induce autophagy in macrophages and modulate the M1/M2 polarization of macrophages. Mg2+ -mediated macrophages could facilitate the osteogenic differentiation of BMSCs by regulating autophagy, and this facilitation by Mg2+ -mediated macrophages was closely related to macrophage-derived exosomes, and especially exosomes containing miR-381. However, miR-381 in macrophages did not influence autophagy or the polarization of Mg2+ -mediated macrophages. Furthermore, macrophage-derived exosomes containing miR-381 mainly determined the osteogenic differentiation of BMSCs. Mg2+ -mediated macrophages were shown to promote the osteogenic differentiation of BMSCs via autophagy through reducing miR-381 in macrophage-derived exosomes. In conclusion, our results suggest Mg2+ -mediated macrophage-derived exosomes containing miR-381 as novel vehicles for promoting the osteogenic differentiation of BMSCs.
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Affiliation(s)
- Yong Zhu
- Department of Orthopaedics, Xiangya Hospital of Central South University, Changsha, Hunan, PR China
| | - Shushan Zhao
- Department of Orthopaedics, Xiangya Hospital of Central South University, Changsha, Hunan, PR China
| | - Liang Cheng
- Department of Orthopaedics, Xiangya Hospital of Central South University, Changsha, Hunan, PR China
| | - Zhangyuan Lin
- Department of Orthopaedics, Xiangya Hospital of Central South University, Changsha, Hunan, PR China
| | - Min Zeng
- Department of Orthopaedics, Xiangya Hospital of Central South University, Changsha, Hunan, PR China
| | - Zhe Ruan
- Department of Orthopaedics, Xiangya Hospital of Central South University, Changsha, Hunan, PR China
| | - Buhua Sun
- Department of Orthopaedics, Xiangya Hospital of Central South University, Changsha, Hunan, PR China
| | - Zhongwei Luo
- Department of Orthopaedics, Xiangya Hospital of Central South University, Changsha, Hunan, PR China
| | - Yifu Tang
- Department of Orthopaedics, Xiangya Hospital of Central South University, Changsha, Hunan, PR China.,Department of Orthopaedics, Xiangya Third Hospital of Central South University, Changsha, Hunan, PR China
| | - Haitao Long
- Department of Orthopaedics, Xiangya Hospital of Central South University, Changsha, Hunan, PR China
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Gu JT, Jiao K, Li J, Yan JF, Wang KY, Wang F, Liu Y, Tay FR, Chen JH, Niu LN. Polyphosphate-crosslinked collagen scaffolds for hemostasis and alveolar bone regeneration after tooth extraction. Bioact Mater 2021; 15:68-81. [PMID: 35386354 PMCID: PMC8940764 DOI: 10.1016/j.bioactmat.2021.12.019] [Citation(s) in RCA: 14] [Impact Index Per Article: 4.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/22/2021] [Revised: 12/06/2021] [Accepted: 12/17/2021] [Indexed: 12/11/2022] Open
Abstract
Post-extraction bleeding and alveolar bone resorption are the two frequently encountered complications after tooth extraction that result in poor healing and rehabilitation difficulties. The present study covalently bonded polyphosphate onto a collagen scaffold (P-CS) by crosslinking. The P-CS demonstrated improved hemostatic property in a healthy rat model and an anticoagulant-treated rat model. This improvement is attributed to the increase in hydrophilicity, increased thrombin generation, platelet activation and stimulation of the intrinsic coagulation pathway. In addition, the P-CS promoted the in-situ bone regeneration and alveolar ridge preservation in a rat alveolar bone defect model. The promotion is attributed to enhanced osteogenic differentiation of bone marrow stromal cells. Osteogenesis was improved by both polyphosphate and blood clots. Taken together, P-CS possesses favorable hemostasis and alveolar ridge preservation capability. It may be used as an effective treatment option for post-extraction bleeding and alveolar bone loss. Statement of significance Collagen scaffold is commonly used for the treatment of post-extraction bleeding and alveolar bone loss after tooth extraction. However, its application is hampered by insufficient hemostatic and osteoinductive property. Crosslinking polyphosphate with collagen produces a modified collagen scaffold that possesses improved hemostatic performance and augmented bone regeneration potential. Polyphosphate-crosslinked collagen scaffold (P-CS) showed better hemostatic effect in healthy or anticoagulant-treated rats. The promoted bone regeneration ability of P-CS might also be related to the clot alteration caused by polyphosphate. P-CS has therapeutic potential in bleeding control and alveolar ridge preservation after tooth extraction.
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Affiliation(s)
- Jun-ting Gu
- National Clinical Research Center for Oral Diseases, State Key Laboratory of Military Stomatology, Shaanxi Key Laboratory of Stomatology, Department of Prosthodontics, School of Stomatology, The Fourth Military Medical University, Xi'an, Shaanxi, China
| | - Kai Jiao
- National Clinical Research Center for Oral Diseases, State Key Laboratory of Military Stomatology, Shaanxi Key Laboratory of Stomatology, Department of Prosthodontics, School of Stomatology, The Fourth Military Medical University, Xi'an, Shaanxi, China
| | - Jing Li
- National Clinical Research Center for Oral Diseases, State Key Laboratory of Military Stomatology, Shaanxi Key Laboratory of Stomatology, Department of Prosthodontics, School of Stomatology, The Fourth Military Medical University, Xi'an, Shaanxi, China
| | - Jian-fei Yan
- National Clinical Research Center for Oral Diseases, State Key Laboratory of Military Stomatology, Shaanxi Key Laboratory of Stomatology, Department of Prosthodontics, School of Stomatology, The Fourth Military Medical University, Xi'an, Shaanxi, China
| | - Kai-yan Wang
- National Clinical Research Center for Oral Diseases, State Key Laboratory of Military Stomatology, Shaanxi Key Laboratory of Stomatology, Department of Prosthodontics, School of Stomatology, The Fourth Military Medical University, Xi'an, Shaanxi, China
| | - Fu Wang
- National Clinical Research Center for Oral Diseases, State Key Laboratory of Military Stomatology, Shaanxi Key Laboratory of Stomatology, Department of Prosthodontics, School of Stomatology, The Fourth Military Medical University, Xi'an, Shaanxi, China
| | - Yan Liu
- National Clinical Research Center for Oral Diseases, State Key Laboratory of Military Stomatology, Shaanxi Key Laboratory of Stomatology, Department of Prosthodontics, School of Stomatology, The Fourth Military Medical University, Xi'an, Shaanxi, China
| | - Franklin R. Tay
- Department of Endodontics, The Dental College of Georgia, Augusta University, Augusta, GA, 30912, USA
| | - Ji-hua Chen
- National Clinical Research Center for Oral Diseases, State Key Laboratory of Military Stomatology, Shaanxi Key Laboratory of Stomatology, Department of Prosthodontics, School of Stomatology, The Fourth Military Medical University, Xi'an, Shaanxi, China
| | - Li-na Niu
- National Clinical Research Center for Oral Diseases, State Key Laboratory of Military Stomatology, Shaanxi Key Laboratory of Stomatology, Department of Prosthodontics, School of Stomatology, The Fourth Military Medical University, Xi'an, Shaanxi, China
- Corresponding author. School of Stomatology, The Fourth Military Medical University, Xi'an, China.
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6
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Yang Y, Xiao Y. Biomaterials Regulating Bone Hematoma for Osteogenesis. Adv Healthc Mater 2020; 9:e2000726. [PMID: 32691989 DOI: 10.1002/adhm.202000726] [Citation(s) in RCA: 14] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/30/2020] [Revised: 06/18/2020] [Indexed: 12/11/2022]
Abstract
Blood coagulation in tissue healing not only prevents blood loss, but also forms a natural scaffold for tissue repair and regeneration. As blood clot formation is the initial and foremost phase upon bone injury, and the quality of blood clot (hematoma) orchestrates the following inflammatory and cellular processes as well as the subsequent callus formation and bone remodeling process. Inspired by the natural healing hematoma, tissue-engineered biomimic scaffold/hydrogels and blood prefabrication strategies attract significant interests in developing functional bone substitutes. The alteration of the fracture hematoma ca significantly accelerate or impair the overall bone healing process. This review summarizes the impact of biomaterials on blood coagulation and provides evidence on fibrin network structure, growth factors, and biomolecules that contribute to bone healing within the hematoma. The aim is to provide insights into the development of novel implant and bone biomaterials for enhanced osteogenesis. Advances in the understanding of biomaterial characteristics (e.g., morphology, chemistry, wettability, and protein adsorption) and their effect on hematoma properties are highlighted. Emphasizing the importance of the initial healing phase of the hematoma endows the design of advanced biomaterials with the desired regulatory properties for optimal coagulation and hematoma properties, thereby facilitating enhanced osteogenesis and ideal therapeutic effects.
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Affiliation(s)
- Ying Yang
- Institute of Health and Biomedical Innovation, Queensland University of Technology, Brisbane, QLD, 4059, Australia
- Australia-China Centre for Tissue Engineering and Regenerative Medicine, Queensland University of Technology, Brisbane, QLD, 4059, Australia
| | - Yin Xiao
- Institute of Health and Biomedical Innovation, Queensland University of Technology, Brisbane, QLD, 4059, Australia
- Australia-China Centre for Tissue Engineering and Regenerative Medicine, Queensland University of Technology, Brisbane, QLD, 4059, Australia
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Stumbras A, Kuliesius P, Darinskas A, Kubilius R, Zigmantaite V, Juodzbalys G. Bone regeneration in rabbit calvarial defects using PRGF and adipose-derived stem cells: histomorphometrical analysis. Regen Med 2020; 15:1535-1549. [PMID: 32452715 DOI: 10.2217/rme-2019-0123] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/14/2023] Open
Abstract
Aim: The aim of this study was to evaluate the osteogenic potential of adipose-derived stem cells (ADSCs) and to assess the influence of plasma rich in growth factors (PRGF) on bone regeneration using ADSCs. Materials & methods: Bone defects were randomly allocated to the five treatment modalities: spontaneous healing, natural bovine bone mineral (BBM), BBM loaded with PRGF, BBM loaded with ADSCs and BBM loaded with a combination of ADSCs and PRGF. Results: The PRGF significantly enhanced the biomaterial-to-bone contact. Defects treated with ADSCs and PRGF or a combination of both showed the greatest bone regeneration. Conclusion: Combining PRGF and ADSCs boosts the bone graft regenerative potential at the earliest period of healing.
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Affiliation(s)
- Arturas Stumbras
- Department of Maxillofacial Surgery, Faculty of Odontology, Lithuanian University of Health Sciences, Kaunas, Lithuania
| | - Povilas Kuliesius
- Department of Maxillofacial Surgery, Faculty of Odontology, Lithuanian University of Health Sciences, Kaunas, Lithuania
| | - Adas Darinskas
- Laboratory of Immunology, National Cancer Institute, Lithuania
| | - Ricardas Kubilius
- Department of Maxillofacial Surgery, Faculty of Odontology, Lithuanian University of Health Sciences, Kaunas, Lithuania
| | - Vilma Zigmantaite
- Animal Research Centre, Lithuanian University of Health Sciences, Kaunas, Lithuania
| | - Gintaras Juodzbalys
- Department of Maxillofacial Surgery, Faculty of Odontology, Lithuanian University of Health Sciences, Kaunas, Lithuania
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Wang X, Luo Y, Yang Y, Zheng B, Yan F, Wei F, Friis TE, Crawford RW, Xiao Y. Alteration of clot architecture using bone substitute biomaterials (beta-tricalcium phosphate) significantly delays the early bone healing process. J Mater Chem B 2018; 6:8204-8213. [PMID: 32254940 DOI: 10.1039/c8tb01747f] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/18/2023]
Abstract
When a bone substitute biomaterial is implanted into the body, the material's surface comes into contact with circulating blood, which results in the formation of a peri-implant hematoma or blood clot. Although hematoma formation is vital for the early bone healing process, knowledge concerning the biomaterial-induced structural properties of blood clots is limited. Here, we report that implantation of beta-tricalcium phosphate (β-TCP) in a bone defect healing model in rats resulted in significantly delayed early bone healing compared to empty controls (natural healing). In vitro studies showed that β-TCP had a profound effect on the overall structure of hematomas, as was observed by fibrin turbidity, scanning electron microscopy (SEM), compaction assays, and fibrinolysis. Under the influence of β-TCP, clot formation had a significantly shortened lag time and there was enhanced lateral fibrin aggregation during the clot polymerization, which resulted in clots composed of thinner fibers. Furthermore, fibrin clots that formed around β-TCP exhibited reduced compaction and increased resistance to fibrinolysis. Together, these results provide a plausible mechanism for how implanted bone-substitute materials may impact the structural properties of the hematoma, thereby altering the early bone healing processes, such as cell infiltration, growth factor release and angiogenesis.
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Affiliation(s)
- Xin Wang
- Department of Orthopaedic Surgery, Affiliated Hospital of Zunyi Medical University, Zunyi, Guizhou 563000, China
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Cheng P, Li D, Gao Y, Cao T, Jiang H, Wang J, Li J, Zhang S, Song Y, Liu B, Wang C, Yang L, Pei G. Prevascularization promotes endogenous cell-mediated angiogenesis by upregulating the expression of fibrinogen and connective tissue growth factor in tissue-engineered bone grafts. Stem Cell Res Ther 2018; 9:176. [PMID: 29973254 PMCID: PMC6030739 DOI: 10.1186/s13287-018-0925-y] [Citation(s) in RCA: 14] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/27/2018] [Revised: 05/29/2018] [Accepted: 06/13/2018] [Indexed: 12/12/2022] Open
Abstract
BACKGROUND Vascularization is one of the most important processes in tissue-engineered bone graft (TEBG)-mediated regeneration of large segmental bone defects. We previously showed that prevascularization of TEBGs promoted capillary vessel formation within the defected site and accelerated new bone formation. However, the precise mechanisms and contribution of endogenous cells were not explored. METHODS We established a large defect (5 mm) model in the femur of EGFP+ transgenic rats and implanted a β-tricalcium phosphate (β-TCP) scaffold seeded with exogenous EGFP- cells; the femoral vascular bundle was inserted into the scaffold before implantation in the prevascularized TEBG group. Histopathology and scanning electron microscopy were performed and connective tissue growth factor (CTGF) and fibrin expression, exogenous cell survival, endogenous cell migration and behavior, and collagen type I and III deposition were assessed at 1 and 4 weeks post implantation. RESULTS We found that the fibrinogen content can be increased at the early stage of vascular bundle transplantation, forming a fibrin reticulate structure and tubular connections between pores of β-TCP material, which provides a support for cell attachment and migration. Meanwhile, CTGF expression is increased, and more endogenous cells can be recruited and promote collagen synthesis and angiogenesis. By 4 weeks post implantation, the tubular connections transformed into von Willebrand factor-positive capillary-like structures with deposition of type III collagen, and accelerated angiogenesis of endogenous cells. CONCLUSIONS These findings demonstrate that prevascularization promotes the recruitment of endogenous cells and collagen deposition by upregulating fibrinogen and CTGF, directly resulting in new blood vessel formation. In addition, this molecular mechanism can be used to establish fast-acting angiogenesis materials in future clinical applications.
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Affiliation(s)
- Pengzhen Cheng
- Institute of Orthopedic Surgery, Xijing Hospital, Fourth Military Medical University, Xi'an, 710032, People's Republic of China
| | - Donglin Li
- Institute of Orthopedic Surgery, Xijing Hospital, Fourth Military Medical University, Xi'an, 710032, People's Republic of China.,Hospital 463 of People's Liberation Army, Shenyang, 110042, People's Republic of China
| | - Yi Gao
- Institute of Orthopedic Surgery, Xijing Hospital, Fourth Military Medical University, Xi'an, 710032, People's Republic of China
| | - Tianqing Cao
- Institute of Orthopedic Surgery, Xijing Hospital, Fourth Military Medical University, Xi'an, 710032, People's Republic of China
| | - Huijie Jiang
- Institute of Orthopedic Surgery, Xijing Hospital, Fourth Military Medical University, Xi'an, 710032, People's Republic of China
| | - Jimeng Wang
- Institute of Orthopedic Surgery, Xijing Hospital, Fourth Military Medical University, Xi'an, 710032, People's Republic of China.,Department of Orthopedics, The 251st Hospital of PLA, Zhangjiakou, 075000, China
| | - Junqin Li
- Institute of Orthopedic Surgery, Xijing Hospital, Fourth Military Medical University, Xi'an, 710032, People's Republic of China
| | - Shuaishuai Zhang
- Institute of Orthopedic Surgery, Xijing Hospital, Fourth Military Medical University, Xi'an, 710032, People's Republic of China
| | - Yue Song
- Institute of Orthopedic Surgery, Xijing Hospital, Fourth Military Medical University, Xi'an, 710032, People's Republic of China
| | - Bin Liu
- Institute of Orthopedic Surgery, Xijing Hospital, Fourth Military Medical University, Xi'an, 710032, People's Republic of China
| | - Chunmei Wang
- Institute of Orthopedic Surgery, Xijing Hospital, Fourth Military Medical University, Xi'an, 710032, People's Republic of China
| | - Liu Yang
- Institute of Orthopedic Surgery, Xijing Hospital, Fourth Military Medical University, Xi'an, 710032, People's Republic of China.
| | - Guoxian Pei
- Institute of Orthopedic Surgery, Xijing Hospital, Fourth Military Medical University, Xi'an, 710032, People's Republic of China.
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