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Wei E, Hu M, Wu L, Pan X, Zhu Q, Liu H, Liu Y. TGF-β signaling regulates differentiation of MSCs in bone metabolism: disputes among viewpoints. Stem Cell Res Ther 2024; 15:156. [PMID: 38816830 PMCID: PMC11140988 DOI: 10.1186/s13287-024-03761-w] [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: 11/07/2023] [Accepted: 05/14/2024] [Indexed: 06/01/2024] Open
Abstract
Mesenchymal stem cells (MSCs) are multipotent cells that can differentiate into cells of different lineages to form mesenchymal tissues, which are promising in regard to treatment for bone diseases. Their osteogenic differentiation is under the tight regulation of intrinsic and extrinsic factors. Transforming growth factor β (TGF-β) is an essential growth factor in bone metabolism, which regulates the differentiation of MSCs. However, published studies differ in their views on whether TGF-β signaling regulates the osteogenic differentiation of MSCs positively or negatively. The controversial results have not been summarized systematically and the related explanations are required. Therefore, we reviewed the basics of TGF-β signaling and summarized how each of three isoforms regulates osteogenic differentiation. Three isoforms of TGF-β (TGF-β1/β2/β3) play distinct roles in regulating osteogenic differentiation of MSCs. Additionally, other possible sources of conflicts are summarized here. Further understanding of TGF-β signaling regulation in MSCs may lead to new applications to promote bone regeneration and improve therapies for bone diseases.
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Affiliation(s)
- Erfan Wei
- Department of Prosthodontics, Peking University School and Hospital of Stomatology & National Center for Stomatology & National Clinical Research Center for Oral Diseases & National Engineering Research Center of Oral Biomaterials and Digital Medical Devices& Beijing Key Laboratory of Digital Stomatology & NHC Key Laboratory of Digital Stomatology & NMPA Key Laboratory for Dental Materials, Central Laboratory, Peking University School and Hospital of Stomatology , No.22, Zhongguancun South Avenue, Haidian District, Beijing, 100081, PR China
| | - Menglong Hu
- Department of Prosthodontics, Peking University School and Hospital of Stomatology & National Center for Stomatology & National Clinical Research Center for Oral Diseases & National Engineering Research Center of Oral Biomaterials and Digital Medical Devices& Beijing Key Laboratory of Digital Stomatology & NHC Key Laboratory of Digital Stomatology & NMPA Key Laboratory for Dental Materials, Central Laboratory, Peking University School and Hospital of Stomatology , No.22, Zhongguancun South Avenue, Haidian District, Beijing, 100081, PR China
| | - Likun Wu
- Department of Prosthodontics, Peking University School and Hospital of Stomatology & National Center for Stomatology & National Clinical Research Center for Oral Diseases & National Engineering Research Center of Oral Biomaterials and Digital Medical Devices& Beijing Key Laboratory of Digital Stomatology & NHC Key Laboratory of Digital Stomatology & NMPA Key Laboratory for Dental Materials, Central Laboratory, Peking University School and Hospital of Stomatology , No.22, Zhongguancun South Avenue, Haidian District, Beijing, 100081, PR China
| | - Xingtong Pan
- Department of Prosthodontics, Peking University School and Hospital of Stomatology & National Center for Stomatology & National Clinical Research Center for Oral Diseases & National Engineering Research Center of Oral Biomaterials and Digital Medical Devices& Beijing Key Laboratory of Digital Stomatology & NHC Key Laboratory of Digital Stomatology & NMPA Key Laboratory for Dental Materials, Central Laboratory, Peking University School and Hospital of Stomatology , No.22, Zhongguancun South Avenue, Haidian District, Beijing, 100081, PR China
| | - Qiyue Zhu
- Department of Prosthodontics, Peking University School and Hospital of Stomatology & National Center for Stomatology & National Clinical Research Center for Oral Diseases & National Engineering Research Center of Oral Biomaterials and Digital Medical Devices& Beijing Key Laboratory of Digital Stomatology & NHC Key Laboratory of Digital Stomatology & NMPA Key Laboratory for Dental Materials, Central Laboratory, Peking University School and Hospital of Stomatology , No.22, Zhongguancun South Avenue, Haidian District, Beijing, 100081, PR China
| | - Hao Liu
- Central Laboratory, Peking University School and Hospital of Stomatology & National Center for Stomatology & National Clinical Research Center for Oral Diseases & National Engineering Research Center of Oral Biomaterials and Digital Medical Devices& Beijing Key Laboratory of Digital Stomatology & NHC Key Laboratory of Digital Stomatology & NMPA Key Laboratory for Dental Materials , Peking University School and Hospital of Stomatology, No.22, Zhongguancun South Avenue, Haidian District, Beijing, 100081, PR China.
| | - Yunsong Liu
- Department of Prosthodontics, Peking University School and Hospital of Stomatology & National Center for Stomatology & National Clinical Research Center for Oral Diseases & National Engineering Research Center of Oral Biomaterials and Digital Medical Devices& Beijing Key Laboratory of Digital Stomatology & NHC Key Laboratory of Digital Stomatology & NMPA Key Laboratory for Dental Materials, Central Laboratory, Peking University School and Hospital of Stomatology , No.22, Zhongguancun South Avenue, Haidian District, Beijing, 100081, PR China.
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Gao J, Liu X, Cheng J, Deng J, Han Z, Li M, Wang X, Liu J, Zhang L. Application of photocrosslinkable hydrogels based on photolithography 3D bioprinting technology in bone tissue engineering. Regen Biomater 2023; 10:rbad037. [PMID: 37250979 PMCID: PMC10219790 DOI: 10.1093/rb/rbad037] [Citation(s) in RCA: 4] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/01/2023] [Revised: 04/02/2023] [Accepted: 04/16/2023] [Indexed: 05/31/2023] Open
Abstract
Bone tissue engineering (BTE) has been proven to be an effective method for the treatment of bone defects caused by different musculoskeletal disorders. Photocrosslinkable hydrogels (PCHs) with good biocompatibility and biodegradability can significantly promote the migration, proliferation and differentiation of cells and have been widely used in BTE. Moreover, photolithography 3D bioprinting technology can notably help PCHs-based scaffolds possess a biomimetic structure of natural bone, meeting the structural requirements of bone regeneration. Nanomaterials, cells, drugs and cytokines added into bioinks can enable different functionalization strategies for scaffolds to achieve the desired properties required for BTE. In this review, we demonstrate a brief introduction of the advantages of PCHs and photolithography-based 3D bioprinting technology and summarize their applications in BTE. Finally, the challenges and potential future approaches for bone defects are outlined.
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Affiliation(s)
| | | | | | - Junhao Deng
- Department of Orthopaedics, Chinese PLA General Hospital, Beijing 100036, China
| | - Zhenchuan Han
- Department of Orthopaedics, Chinese PLA General Hospital, Beijing 100036, China
| | - Ming Li
- Department of Orthopaedics, Chinese PLA General Hospital, Beijing 100036, China
| | - Xiumei Wang
- Correspondence address: E-mail: (X.W); (J.L.); (L.Z.)
| | - Jianheng Liu
- Correspondence address: E-mail: (X.W); (J.L.); (L.Z.)
| | - Licheng Zhang
- Correspondence address: E-mail: (X.W); (J.L.); (L.Z.)
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Le Fer G, Dilla RA, Wang Z, King J, Chuang SSC, Becker ML. Clustering and Hierarchical Organization of 3D Printed Poly(propylene fumarate)- block-PEG- block-poly(propylene fumarate) ABA Triblock Copolymer Hydrogels. Macromolecules 2021. [DOI: 10.1021/acs.macromol.1c00132] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/15/2022]
Affiliation(s)
- Gaëlle Le Fer
- Univ. Lille, CNRS, INRAE, Centrale Lille, UMR 8207—UMET—Unité Matériaux et Transformations, F-59000 Lille, France
- School of Polymer Science and Polymer Engineering, The University of Akron, Akron, Ohio 44325, United States
| | - Rodger A. Dilla
- School of Polymer Science and Polymer Engineering, The University of Akron, Akron, Ohio 44325, United States
| | - Zeyu Wang
- School of Polymer Science and Polymer Engineering, The University of Akron, Akron, Ohio 44325, United States
| | - Jaelynne King
- School of Polymer Science and Polymer Engineering, The University of Akron, Akron, Ohio 44325, United States
| | - Steven S. C. Chuang
- School of Polymer Science and Polymer Engineering, The University of Akron, Akron, Ohio 44325, United States
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Le Fer G, Becker ML. 4D Printing of Resorbable Complex Shape-Memory Poly(propylene fumarate) Star Scaffolds. ACS APPLIED MATERIALS & INTERFACES 2020; 12:22444-22452. [PMID: 32337967 DOI: 10.1021/acsami.0c01444] [Citation(s) in RCA: 36] [Impact Index Per Article: 9.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/11/2023]
Abstract
3D/4D printing is enabling transformative advances in device manufacturing and medicine but remains limited by the lack of printable resorbable materials with advanced properties and functions. Herein, we report the rapid and precise 4D printing of shape-memory scaffolds based on poly(propylene fumarate) (PPF) star polymers. Scaffolds with tunable and distinguishable properties can be produced with identical polymer formulation and stoichiometry. The resulting scaffold glass transition temperatures and Young's moduli increase with the postcuring time. Significantly, both the extent and rate of shape recovery following compression can be tuned by varying the strut design, the postcuring step duration, and/or the temperature applied for the recovery step. Finally, accelerated degradation studies confirmed the resorbability of the PPF star polymer gyroid scaffolds.
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Affiliation(s)
- Gaëlle Le Fer
- Department of Polymer Science, The University of Akron, Akron, Ohio 44325, United States
| | - Matthew L Becker
- Department of Polymer Science, The University of Akron, Akron, Ohio 44325, United States
- Department of Chemistry, Duke University, Durham, North Carolina 27708, United States
- Department of Mechanical Engineering and Material Science, Duke University, Durham, North Carolina 27708, United States
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5
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Cai Z, Wan Y, Becker ML, Long YZ, Dean D. Poly(propylene fumarate)-based materials: Synthesis, functionalization, properties, device fabrication and biomedical applications. Biomaterials 2019; 208:45-71. [PMID: 30991217 DOI: 10.1016/j.biomaterials.2019.03.038] [Citation(s) in RCA: 54] [Impact Index Per Article: 10.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/21/2018] [Revised: 03/04/2019] [Accepted: 03/23/2019] [Indexed: 12/22/2022]
Abstract
Poly(propylene fumarate) (PPF) is a biodegradable polymer that has been investigated extensively over the last three decades. It has led many scientists to synthesize and fabricate a variety of PPF-based materials for biomedical applications due to its controllable mechanical properties, tunable degradation and biocompatibility. This review provides a comprehensive overview of the progress made in improving PPF synthesis, resin formulation, crosslinking, device fabrication and post polymerization modification. Further, we highlight the influence of these parameters on biodegradation, biocompatibility, and their use in a number of regenerative medicine applications, especially bone tissue engineering. In particular, the use of 3D printing techniques for the fabrication of PPF-based scaffolds is extensively reviewed. The recent invention of a ring-opening polymerization method affords precise control of PPF molecular mass, molecular mass distribution (ƉM) and viscosity. Low ƉM facilitates time-certain resorption of 3D printed structures. Novel post-polymerization and post-printing functionalization methods have accelerated the expansion of biomedical applications that utilize PPF-based materials. Finally, we shed light on evolving uses of PPF-based materials for orthopedics/bone tissue engineering and other biomedical applications, including its use as a hydrogel for bioprinting.
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Affiliation(s)
- Zhongyu Cai
- Department of Chemical and Biomolecular Engineering, National University of Singapore, 4 Engineering Drive 4, 117585, Singapore; Department of Chemistry, University of Pittsburgh, Chevron Science Center, 219 Parkman Avenue, Pittsburgh, PA 15260, United States.
| | - Yong Wan
- Collaborative Innovation Center for Nanomaterials, College of Physics, Qingdao University, No. 308 Ningxia Road, Qingdao, 266071, Shandong Province, China
| | - Matthew L Becker
- Department of Polymer Science, The University of Akron, Akron, OH 44325, United States
| | - Yun-Ze Long
- Collaborative Innovation Center for Nanomaterials, College of Physics, Qingdao University, No. 308 Ningxia Road, Qingdao, 266071, Shandong Province, China; Industrial Research Institute of Nonwovens & Technical Textiles, Qingdao University, No. 308 Ningxia Road, Qingdao, 266071, Shandong Province, China.
| | - David Dean
- Department of Plastic & Reconstructive Surgery, The Ohio State University, Columbus, OH 43210, United States.
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6
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Luo Y, Le Fer G, Dean D, Becker ML. 3D Printing of Poly(propylene fumarate) Oligomers: Evaluation of Resin Viscosity, Printing Characteristics and Mechanical Properties. Biomacromolecules 2019; 20:1699-1708. [PMID: 30807696 DOI: 10.1021/acs.biomac.9b00076] [Citation(s) in RCA: 55] [Impact Index Per Article: 11.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/05/2023]
Abstract
Complex three-dimensional (3D) pore geometries, useful for tissue engineering scaffolds, can be fabricated via photo-crosslinking of resorbable poly(propylene fumarate) (PPF) resins using stereolithography (SLA) and/or continuous digital light processing (cDLP) methods. Physico-chemical parameters inherent to 3D printable resin design, include viscosity, polymer concentration, degree of polymerization, and resin printing temperature. We report here on our study of these parameters and their influence the cDLP 3D printing process and the resulting mechanical properties. A series of PPF oligomers were synthesized by the ring-opening copolymerization (ROCOP) of maleic anhydride and propylene oxide followed by a base-catalyzed isomerization. The resin viscosities were measured as a function of number-average molecular mass ([Formula: see text]) of the PPF oligomers (1.1, 1.7 and 2.0 kDa), concentrations of PPF in the reactive diluent diethyl fumarate (DEF) (50 and 75 wt %) and resin temperature (25 to 55 °C). The zero-shear viscosity (η0) of the resins was found to be temperature-dependent and follow a linear Arrhenius relationship. Tensile tests demonstrated mechanical properties within the range of trabecular bone, with the ultimate strength at break above 15 MPa and elastic moduli between 178 and 199 MPa.
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Affiliation(s)
- Yuanyuan Luo
- Department of Polymer Science , The University of Akron , Akron , Ohio 44325 , United States
| | - Gaëlle Le Fer
- Department of Polymer Science , The University of Akron , Akron , Ohio 44325 , United States
| | - David Dean
- Department of Plastic Surgery , The Ohio State University , Columbus , Ohio 43210 , United States
| | - Matthew L Becker
- Department of Polymer Science , The University of Akron , Akron , Ohio 44325 , United States
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7
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Le Fer G, Luo Y, Becker ML. Poly(propylene fumarate) stars, using architecture to reduce the viscosity of 3D printable resins. Polym Chem 2019. [DOI: 10.1039/c9py00738e] [Citation(s) in RCA: 21] [Impact Index Per Article: 4.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/05/2023]
Abstract
Additive manufacturing is changing tissue engineering by offering pathways to otherwise unattainable, highly complex scaffold morphologies.
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Affiliation(s)
- Gaëlle Le Fer
- Department of Polymer Science
- University of Akron
- Akron
- USA
| | - Yuanyuan Luo
- Department of Polymer Science
- University of Akron
- Akron
- USA
| | - Matthew L. Becker
- Department of Polymer Science
- University of Akron
- Akron
- USA
- Department of Chemistry
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8
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Tissue Engineering in Ophthalmology: Implications for Eyelid Reconstruction. Ophthalmic Plast Reconstr Surg 2017; 33:157-162. [PMID: 27749619 DOI: 10.1097/iop.0000000000000792] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/17/2023]
Abstract
PURPOSE Bioengineering aims to produce functional tissue replacements to repair defects and has been widely investigated over the past few decades. We aimed to review the available literature on the application of tissue engineering in ophthalmology, with a particular focus on ophthalmic plastic surgery and potential applications for eyelid reconstruction. METHODS A literature search was performed on the MEDLINE database using the keywords "bioengineering," "tissue engineering," and "ophthalmology." Articles written in English were included. RESULTS There is a substantial body of work on tissue engineering of the cornea. Other structures in ophthalmology investigated include the conjunctiva, lacrimal gland, and orbital bone. We also discuss the potential application of tissue engineering in eyelid reconstruction. CONCLUSION Tissue engineering represents the future of regenerative and reconstructive medicine, with significant potential applications in ophthalmic plastic surgery.
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Yokota K, Matsuno T, Tabata Y, Mataga I. Evaluation of a Porous Hydroxyapatite Granule and Gelatin Hydrogel Microsphere Composite in Bone Regeneration. J HARD TISSUE BIOL 2017. [DOI: 10.2485/jhtb.26.203] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/19/2022]
Affiliation(s)
- Kensho Yokota
- Department of Oral Maxillofacial Surgery, The Nippon Dental University School of Life Dentistry at Tokyo
- Department of Regeneration Science and Engineering, Labatory of Biomaterials, Institute for Frontier Life and Medical Sciences, Kyoto University
| | - Tomonori Matsuno
- Department of Oral Maxillofacial Surgery, The Nippon Dental University School of Life Dentistry at Tokyo
| | - Yasuhiko Tabata
- Department of Regeneration Science and Engineering, Labatory of Biomaterials, Institute for Frontier Life and Medical Sciences, Kyoto University
| | - Izumi Mataga
- Department of Oral Maxillofacial Surgery, The Nippon Dental University School of Life Dentistry at Tokyo
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10
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Affiliation(s)
- Hwa Lee
- Department of Ophthalmology, Korea University Ansan Hospital, Korea University College of Medicine, Ansan, Korea
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11
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Mishra R, Roux BM, Posukonis M, Bodamer E, Brey EM, Fisher JP, Dean D. Effect of prevascularization on in vivo vascularization of poly(propylene fumarate)/fibrin scaffolds. Biomaterials 2015; 77:255-66. [PMID: 26606451 DOI: 10.1016/j.biomaterials.2015.10.026] [Citation(s) in RCA: 65] [Impact Index Per Article: 7.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/05/2015] [Revised: 10/11/2015] [Accepted: 10/12/2015] [Indexed: 12/31/2022]
Abstract
The importance of vascularization in the field of bone tissue engineering has been established by previous studies. The present work proposes a novel poly(propylene fumarate) (PPF)/fibrin composite scaffold for the development of vascularized neobone tissue. The effect of prevascularization (i.e., in vitro pre-culture prior to implantation) with human mesenchymal stem cells (hMSCs) and human umbilical vein endothelial cells (HUVECs) on in vivo vascularization of scaffolds was determined. Five conditions were studied: no pre-culture (NP), 1 week pre-culture (1P), 2 week pre-culture (2P), 3 week pre-culture (3P), and scaffolds without cells (control, C). Scaffolds were implanted subcutaneously in a severe combined immunodeficiency (SCID) mouse model for 9 days. During in vitro studies, CD31 staining showed a significant increase in vascular network area over 3 weeks of culture. Vascular density was significantly higher in vivo when comparing the NP and 3P groups. Immunohistochemical staining of human CD-31 expression indicated spreading of vascular networks with increasing pre-culture time. These vascular networks were perfused with mouse blood indicated by perfused lectin staining in human CD-31 positive vessels. Our results demonstrate that in vitro prevascularization supports in vivo vascularization in PPF/fibrin scaffolds.
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Affiliation(s)
- Ruchi Mishra
- Department of Plastic Surgery, The Ohio State University, Columbus, OH, USA
| | - Brianna M Roux
- Department of Biomedical Engineering, Illinois Institute of Technology, Chicago, IL, USA; Research Service, Edward Hines Jr. V.A. Hospital, Hines, IL, USA
| | - Megan Posukonis
- Department of Plastic Surgery, The Ohio State University, Columbus, OH, USA
| | - Emily Bodamer
- Department of Plastic Surgery, The Ohio State University, Columbus, OH, USA
| | - Eric M Brey
- Department of Biomedical Engineering, Illinois Institute of Technology, Chicago, IL, USA; Research Service, Edward Hines Jr. V.A. Hospital, Hines, IL, USA
| | - John P Fisher
- Fischell Department of Bioengineering, University of Maryland, College Park, MD, USA
| | - David Dean
- Department of Plastic Surgery, The Ohio State University, Columbus, OH, USA.
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12
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A novel animal model treated with tooth extraction to repair the full-thickness defects in the mandible of rabbits. J Surg Res 2015; 194:706-716. [DOI: 10.1016/j.jss.2014.11.010] [Citation(s) in RCA: 13] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/04/2014] [Revised: 10/29/2014] [Accepted: 11/07/2014] [Indexed: 11/22/2022]
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13
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Wallace J, Wang MO, Thompson P, Busso M, Belle V, Mammoser N, Kim K, Fisher JP, Siblani A, Xu Y, Welter JF, Lennon DP, Sun J, Caplan AI, Dean D. Validating continuous digital light processing (cDLP) additive manufacturing accuracy and tissue engineering utility of a dye-initiator package. Biofabrication 2014; 6:015003. [PMID: 24429508 DOI: 10.1088/1758-5082/6/1/015003] [Citation(s) in RCA: 47] [Impact Index Per Article: 4.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/05/2023]
Abstract
This study tested the accuracy of tissue engineering scaffold rendering via the continuous digital light processing (cDLP) light-based additive manufacturing technology. High accuracy (i.e., <50 µm) allows the designed performance of features relevant to three scale spaces: cell-scaffold, scaffold-tissue, and tissue-organ interactions. The biodegradable polymer poly (propylene fumarate) was used to render highly accurate scaffolds through the use of a dye-initiator package, TiO2 and bis (2,4,6-trimethylbenzoyl)phenylphosphine oxide. This dye-initiator package facilitates high accuracy in the Z dimension. Linear, round, and right-angle features were measured to gauge accuracy. Most features showed accuracies between 5.4-15% of the design. However, one feature, an 800 µm diameter circular pore, exhibited a 35.7% average reduction of patency. Light scattered in the x, y directions by the dye may have reduced this feature's accuracy. Our new fine-grained understanding of accuracy could be used to make further improvements by including corrections in the scaffold design software. Successful cell attachment occurred with both canine and human mesenchymal stem cells (MSCs). Highly accurate cDLP scaffold rendering is critical to the design of scaffolds that both guide bone regeneration and that fully resorb. Scaffold resorption must occur for regenerated bone to be remodeled and, thereby, achieve optimal strength.
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Affiliation(s)
- Jonathan Wallace
- Department of Biomedical Engineering, Case Western Reserve University, Cleveland, OH 44106, USA
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Ferreira JR, Padilla R, Urkasemsin G, Yoon K, Goeckner K, Hu WS, Ko CC. Titanium-enriched hydroxyapatite-gelatin scaffolds with osteogenically differentiated progenitor cell aggregates for calvaria bone regeneration. Tissue Eng Part A 2013; 19:1803-16. [PMID: 23495972 DOI: 10.1089/ten.tea.2012.0520] [Citation(s) in RCA: 26] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/03/2023] Open
Abstract
Adequate bony support is the key to re-establish both function and esthetics in the craniofacial region. Autologous bone grafting has been the gold standard for regeneration of problematic large bone defects. However, poor graft availability and donor-site complications have led to alternative bone tissue-engineering approaches combining osteoinductive biomaterials and three-dimensional cell aggregates in scaffolds or constructs. The goal of the present study was to generate novel cell aggregate-loaded macroporous scaffolds combining the osteoinductive properties of titanium dioxide (TiO2) with hydroxyapatite-gelatin nanocomposites (HAP-GEL) for regeneration of craniofacial defects. Here we investigated the in vivo applicability of macroporous (TiO2)-enriched HAP-GEL scaffolds with undifferentiated and osteogenically differentiated multipotent adult progenitor cell (MAPC and OD-MAPC, respectively) aggregates for calvaria bone regeneration. The silane-coated HAP-GEL with and without TiO2 additives were polymerized and molded to produce macroporous scaffolds. Aggregates of the rat MAPC were precultured, loaded into each scaffold, and implanted to rat calvaria critical-size defects to study bone regeneration. Bone autografts were used as positive controls and a poly(lactic-co-glycolic acid) (PLGA) scaffold for comparison purposes. Preimplanted scaffolds and calvaria bone from pig were tested for ultimate compressive strength with an Instron 4411(®) and for porosity with microcomputerized tomography (μCT). Osteointegration and newly formed bone (NFB) were assessed by μCT and nondecalcified histology, and quantified by calcium fluorescence labeling. Results showed that the macroporous TiO2-HAP-GEL scaffold had a comparable strength relative to the natural calvaria bone (13.8±4.5 MPa and 24.5±8.3 MPa, respectively). Porosity was 1.52±0.8 mm and 0.64±0.4 mm for TiO2-HAP-GEL and calvaria bone, respectively. At 8 and 12 weeks postimplantation into rat calvaria defects, greater osteointegration and NFB were significantly present in the TiO2-enriched HAP-GEL constructs with OD-MAPCs, compared to the undifferentiated MAPC-loaded constructs, cell-free HAP-GEL with and without titanium, and PLGA scaffolds. The tissue-engineered TiO2-enriched HAP-GEL constructs with OD-MAPC aggregates present a potential useful therapeutic approach for calvaria bone regeneration.
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Affiliation(s)
- João R Ferreira
- Matrix and Morphogenesis Section, National Institute of Dental and Craniofacial Research, Bethesda, MD 20892, USA.
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15
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Alge DL, Bennett J, Treasure T, Voytik-Harbin S, Goebel WS, Chu TMG. Poly(propylene fumarate) reinforced dicalcium phosphate dihydrate cement composites for bone tissue engineering. J Biomed Mater Res A 2012; 100:1792-802. [PMID: 22489012 DOI: 10.1002/jbm.a.34130] [Citation(s) in RCA: 27] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/02/2011] [Revised: 12/20/2011] [Accepted: 02/16/2012] [Indexed: 01/13/2023]
Abstract
Calcium phosphate cements have many desirable properties for bone tissue engineering, including osteoconductivity, resorbability, and amenability to rapid prototyping-based methods for scaffold fabrication. In this study, we show that dicalcium phosphate dihydrate (DCPD) cements, which are highly resorbable but also inherently weak and brittle, can be reinforced with poly(propylene fumarate) (PPF) to produce strong composites with mechanical properties suitable for bone tissue engineering. Characterization of DCPD-PPF composites revealed significant improvements in mechanical properties for cements with a 1.0 powder to liquid ratio. Compared with nonreinforced controls, flexural strength improved from 1.80 ± 0.19 MPa to 16.14 ± 1.70 MPa, flexural modulus increased from 1073.01 ± 158.40 MPa to 1303.91 ± 110.41 MPa, maximum displacement during testing increased from 0.11 ± 0.04 mm to 0.51 ± 0.09 mm, and work of fracture improved from 2.74 ± 0.78 J/m(2) to 249.21 ± 81.64 J/m(2) . To demonstrate the utility of our approach for scaffold fabrication, 3D macroporous scaffolds were prepared with rapid prototyping technology. Compressive testing revealed that PPF reinforcement increased scaffold strength from 0.31 ± 0.06 MPa to 7.48 ± 0.77 MPa. Finally, 3D PPF-DCPD scaffolds were implanted into calvarial defects in rabbits for 6 weeks. Although the addition of mesenchymal stem cells to the scaffolds did not significantly improve the extent of regeneration, numerous bone nodules with active osteoblasts were observed within the scaffold pores, especially in the peripheral regions. Overall, the results of this study suggest that PPF-DCPD composites may be promising scaffold materials for bone tissue engineering.
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Affiliation(s)
- Daniel L Alge
- Weldon School of Biomedical Engineering, Purdue University, West Lafayette, Indiana 47908, USA
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Costa-Pinto AR, Reis RL, Neves NM. Scaffolds based bone tissue engineering: the role of chitosan. TISSUE ENGINEERING PART B-REVIEWS 2011; 17:331-47. [PMID: 21810029 DOI: 10.1089/ten.teb.2010.0704] [Citation(s) in RCA: 250] [Impact Index Per Article: 19.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 12/25/2022]
Abstract
As life expectancy increases, malfunction or loss of tissue caused by injury or disease leads to reduced quality of life in many patients at significant socioeconomic cost. Even though major progress has been made in the field of bone tissue engineering, present therapies, such as bone grafts, still have limitations. Current research on biodegradable polymers is emerging, combining these structures with osteogenic cells, as an alternative to autologous bone grafts. Different types of biodegradable materials have been proposed for the preparation of three-dimensional porous scaffolds for bone tissue engineering. Among them, natural polymers are one of the most attractive options, mainly due to their similarities with extracellular matrix, chemical versatility, good biological performance, and inherent cellular interactions. In this review, special attention is given to chitosan as a biomaterial for bone tissue engineering applications. An extensive literature survey was performed on the preparation of chitosan scaffolds and their in vitro biological performance as well as their potential to facilitate in vivo bone regeneration. The present review also aims to offer the reader a general overview of all components needed to engineer new bone tissue. It gives a brief background on bone biology, followed by an explanation of all components in bone tissue engineering, as well as describing different tissue engineering strategies. Moreover, also discussed are the typical models used to evaluate in vitro functionality of a tissue-engineered construct and in vivo models to assess the potential to regenerate bone tissue are discussed.
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Affiliation(s)
- Ana Rita Costa-Pinto
- 3B's Research Group-Biomaterials, Biodegradables and Biomimetics, Department of Polymer Engineering, Headquarters of the European Institute of Excellence on Tissue Engineering and Regenerative Medicine University of Minho, Guimarães, Portugal
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17
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Early osteogenic signal expression of rat bone marrow stromal cells is influenced by both hydroxyapatite nanoparticle content and initial cell seeding density in biodegradable nanocomposite scaffolds. Acta Biomater 2011; 7:1249-64. [PMID: 21074640 DOI: 10.1016/j.actbio.2010.11.007] [Citation(s) in RCA: 105] [Impact Index Per Article: 8.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/20/2010] [Revised: 11/01/2010] [Accepted: 11/03/2010] [Indexed: 02/03/2023]
Abstract
Incorporation of hydroxyapatite (HA) within a degradable polymeric scaffold may provide a favorable synthetic microenvironment that more closely mimics natural bone tissue physiology. Both incorporation of HA nanoparticles and alterations of the paracrine cell-cell signaling distance may affect the intercellular signaling mechanism and facilitate enhanced osteogenic signal expression among the implanted cell population. In this study we investigate the effect of the incorporation of HA nanoparticles into poly(propylene fumarate) (PPF) scaffolds on the surface properties of composite scaffolds and early osteogenic growth factor gene expression in relation to initial cell seeding density. The results of surface characterization indicated that HA addition improved the surface properties of PPF/HA composite scaffolds by increasing the roughness, hydrophilicity, protein adsorption, and initial cell attachment. Rat bone marrow stromal cells (BMSCs), which were CD34-, CD45-, CD29+, and CD90+, were cultured on three-dimensional (3-D) macroporous PPF/HA scaffolds at two different initial cell seeding densities (0.33 and 1.00 million cells per scaffold) for 8 days. The results demonstrated that endogenous osteogenic signal expression profiles, including bone morphogenetic protein-2, fibroblast growth factor-2, and transforming growth factor-β1, as well as the transcriptional factor Runx2, were affected by both HA amount and initial cell seeding density. Up-regulated expression of osteogenic growth factor genes was related to subsequent osteoblastic differentiation of rat BMSCs on 3-D scaffolds, as characterized by alkaline phosphatase activity, osteocalcin mRNA expression, and calcium deposition. Thus, the PPF/HA composite scaffold construction parameters, including amount of HA incorporated and initial cell seeding density, may be utilized to induce the osteoblastic differentiation of transplanted rat BMSCs.
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Kim K, Yeatts A, Dean D, Fisher JP. Stereolithographic bone scaffold design parameters: osteogenic differentiation and signal expression. TISSUE ENGINEERING PART B-REVIEWS 2011; 16:523-39. [PMID: 20504065 DOI: 10.1089/ten.teb.2010.0171] [Citation(s) in RCA: 126] [Impact Index Per Article: 9.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/12/2022]
Abstract
Scaffold design parameters including porosity, pore size, interconnectivity, and mechanical properties have a significant influence on osteogenic signal expression and differentiation. This review evaluates the influence of each of these parameters and then discusses the ability of stereolithography (SLA) to be used to tailor scaffold design to optimize these parameters. Scaffold porosity and pore size affect osteogenic cell signaling and ultimately in vivo bone tissue growth. Alternatively, scaffold interconnectivity has a great influence on in vivo bone growth but little work has been done to determine if interconnectivity causes changes in signaling levels. Osteogenic cell signaling could be also influenced by scaffold mechanical properties such as scaffold rigidity and dynamic relationships between the cells and their extracellular matrix. With knowledge of the effects of these parameters on cellular functions, an optimal tissue engineering scaffold can be designed, but a proper technology must exist to produce this design to specification in a repeatable manner. SLA has been shown to be capable of fabricating scaffolds with controlled architecture and micrometer-level resolution. Surgical implantation of these scaffolds is a promising clinical treatment for successful bone regeneration. By applying knowledge of how scaffold parameters influence osteogenic cell signaling to scaffold manufacturing using SLA, tissue engineers may move closer to creating the optimal tissue engineering scaffold.
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Affiliation(s)
- Kyobum Kim
- Department of Chemical and Biomolecular Engineering, University of Maryland, College Park, Maryland 20742, USA
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19
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Kretlow JD, Spicer PP, Jansen JA, Vacanti CA, Kasper FK, Mikos AG. Uncultured marrow mononuclear cells delivered within fibrin glue hydrogels to porous scaffolds enhance bone regeneration within critical-sized rat cranial defects. Tissue Eng Part A 2010; 16:3555-68. [PMID: 20715884 DOI: 10.1089/ten.tea.2010.0471] [Citation(s) in RCA: 53] [Impact Index Per Article: 3.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/13/2022] Open
Abstract
For bone tissue engineering, the benefits of incorporating mesenchymal stem cells (MSCs) into porous scaffolds are well established. There is, however, little consensus on the effects of or need for MSC handling ex vivo. Culture and expansion of MSCs adds length and cost, and likely increases risk associated with treatment. We evaluated the effect of using uncultured bone marrow mononuclear cells (bmMNCs) encapsulated within fibrin glue hydrogels and seeded into porous scaffolds to regenerate bone over 12 weeks in an 8-mm-diameter, critical-sized rat cranial defect. A full factorial experimental design was used to evaluate bone formation within model poly(L-lactic acid) and corraline hydroxyapatite scaffolds with or without platelet-rich plasma (PRP) and bmMNCs. Mechanical push-out testing, microcomputed tomographical analyses, and histology were performed. PRP showed no benefit for bone formation. Cell-laden poly(L-lactic acid) scaffolds without PRP required significantly greater force to displace from surrounding tissues than control (cell-free) scaffolds, but no differences were observed during push-out testing of coral scaffolds. For bone volume formation as analyzed by microcomputed tomography, significant positive overall effects were observed with bmMNC incorporation. These data suggest that bmMNCs may provide therapeutic advantages in bone tissue engineering applications without the need for culture, expansion, and purification.
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Affiliation(s)
- James D Kretlow
- Department of Bioengineering, Rice University, Houston, Texas, USA
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20
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Betz MW, Caccamese JF, Coletti DP, Sauk JJ, Fisher JP. Challenges Associated with Regeneration of Orbital Floor Bone. TISSUE ENGINEERING PART B-REVIEWS 2010; 16:541-50. [DOI: 10.1089/ten.teb.2009.0393] [Citation(s) in RCA: 13] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 01/14/2023]
Affiliation(s)
- Martha W. Betz
- Fischell Department of Bioengineering, University of Maryland, College Park, Maryland
| | - John F. Caccamese
- Department of Oral and Maxillofacial Surgery, University of Maryland Dental School, Baltimore, Maryland
| | - Domenick P. Coletti
- Department of Oral and Maxillofacial Surgery, University of Maryland Dental School, Baltimore, Maryland
| | - John J. Sauk
- University of Louisville, Dental School, Louisville, Kentucky
| | - John P. Fisher
- Fischell Department of Bioengineering, University of Maryland, College Park, Maryland
- Department of Oral and Maxillofacial Surgery, University of Maryland Dental School, Baltimore, Maryland
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Young S, Patel ZS, Kretlow JD, Murphy MB, Mountziaris PM, Baggett LS, Ueda H, Tabata Y, Jansen JA, Wong M, Mikos AG. Dose effect of dual delivery of vascular endothelial growth factor and bone morphogenetic protein-2 on bone regeneration in a rat critical-size defect model. Tissue Eng Part A 2009. [PMID: 19249918 DOI: 10.1089/ten/tea.2008.0510] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/12/2022] Open
Abstract
The dose effect of dual delivery of vascular endothelial growth factor (VEGF) and bone morphogenetic protein-2 (BMP-2) on bone regeneration was investigated in a rat cranial critical-size defect (CSD). It was hypothesized that decreasing amounts of BMP-2 would result in a dose-dependent decrease in bone formation, and that this reduction in bone formation could be reversed by adding increasing amounts of VEGF. In vitro release kinetics of VEGF or BMP-2 were examined over 28 days. Next, scaffolds were implanted within a rat cranial CSD containing different combinations of both BMP-2 and VEGF. At 12 weeks, samples were analyzed using microcomputed tomography and histology. In vitro, VEGF and BMP-2 exhibited burst release in the first 24 h followed by a significant decrease in release rate over 27 days. Overall, BMP-2 had a more sustained release versus VEGF. An in vivo dose-dependent decrease in percentage of bone fill (PBF) was observed for BMP-2. The addition of VEGF was unable to reverse this decrease in PBF, although improvements in the number of bridged defects did occur in some groups. This suggests that for this particular model simultaneous release of BMP-2 and VEGF does not increase bone formation over BMP-2 alone at 12 weeks.
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Affiliation(s)
- Simon Young
- Department of Bioengineering, Rice University, Houston, Texas 77251-1892, USA
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Young S, Patel ZS, Kretlow JD, Murphy MB, Mountziaris PM, Baggett LS, Ueda H, Tabata Y, Jansen JA, Wong M, Mikos AG. Dose effect of dual delivery of vascular endothelial growth factor and bone morphogenetic protein-2 on bone regeneration in a rat critical-size defect model. Tissue Eng Part A 2009; 15:2347-62. [PMID: 19249918 DOI: 10.1089/ten.tea.2008.0510] [Citation(s) in RCA: 213] [Impact Index Per Article: 14.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/22/2022] Open
Abstract
The dose effect of dual delivery of vascular endothelial growth factor (VEGF) and bone morphogenetic protein-2 (BMP-2) on bone regeneration was investigated in a rat cranial critical-size defect (CSD). It was hypothesized that decreasing amounts of BMP-2 would result in a dose-dependent decrease in bone formation, and that this reduction in bone formation could be reversed by adding increasing amounts of VEGF. In vitro release kinetics of VEGF or BMP-2 were examined over 28 days. Next, scaffolds were implanted within a rat cranial CSD containing different combinations of both BMP-2 and VEGF. At 12 weeks, samples were analyzed using microcomputed tomography and histology. In vitro, VEGF and BMP-2 exhibited burst release in the first 24 h followed by a significant decrease in release rate over 27 days. Overall, BMP-2 had a more sustained release versus VEGF. An in vivo dose-dependent decrease in percentage of bone fill (PBF) was observed for BMP-2. The addition of VEGF was unable to reverse this decrease in PBF, although improvements in the number of bridged defects did occur in some groups. This suggests that for this particular model simultaneous release of BMP-2 and VEGF does not increase bone formation over BMP-2 alone at 12 weeks.
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Affiliation(s)
- Simon Young
- Department of Bioengineering, Rice University, Houston, Texas 77251-1892, USA
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Young S, Kretlow JD, Nguyen C, Bashoura AG, Baggett LS, Jansen JA, Wong M, Mikos AG. Microcomputed tomography characterization of neovascularization in bone tissue engineering applications. TISSUE ENGINEERING PART B-REVIEWS 2009; 14:295-306. [PMID: 18657028 DOI: 10.1089/ten.teb.2008.0153] [Citation(s) in RCA: 55] [Impact Index Per Article: 3.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 01/04/2023]
Abstract
Vasculogenesis and angiogenesis have been studied for decades using numerous in vitro and in vivo systems, fulfilling the need to elucidate the mechanisms involved in these processes and to test potential therapeutic agents that inhibit or promote neovascularization. Bone tissue engineering in particular has benefited from the application of proangiogenic strategies, considering the need for an adequate vascular supply during healing and the challenges associated with the vascularization of scaffolds implanted in vivo. Conventional methods of assessing the in vivo angiogenic response to tissue-engineered constructs tend to rely on a two-dimensional assessment of microvessel density within representative histological sections without elaboration of the true vascular tree. The introduction of microcomputed tomography (micro-CT) has recently allowed investigators to obtain a diverse range of high-resolution, three-dimensional characterization of structures, including renal, coronary, and hepatic vascular networks, as well as bone formation within healing defects. To date, few studies have utilized micro-CT to study the vascular response to an implanted tissue engineering scaffold. In this paper, conventional in vitro and in vivo models for studying angiogenesis will be discussed, followed by recent developments in the use of micro-CT for vessel imaging in bone tissue engineering research. A new study demonstrating the potential of contrast-enhanced micro-CT for the evaluation of in vivo neovascularization in bony defects is described, which offers significant potential in the evaluation of bone tissue engineering constructs.
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Affiliation(s)
- Simon Young
- Department of Bioengineering, Rice University, Houston, Texas, USA
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Abstract
This protocol describes the synthesis of 500-4,000 Da poly(propylene fumarate) (PPF) by a two-step reaction of diethyl fumarate and propylene glycol through a bis(hydroxypropyl) fumarate diester intermediate. Purified PPF can be covalently cross-linked to form degradable polymer networks, which have been widely explored for biomedical applications. The properties of cross-linked PPF networks depend upon the molecular properties of the constituent polymer, such as the molecular weight. The purity of the reactants and the exclusion of water from the reaction system are of utmost importance in the generation of high-molecular-weight PPF products. Additionally, the reaction time and temperature influence the molecular weight of the PPF product. The expected time required to complete this protocol is 3 d.
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Young S, Bashoura AG, Borden T, Baggett LS, Jansen JA, Wong M, Mikos AG. Development and characterization of a rabbit alveolar bone nonhealing defect model. J Biomed Mater Res A 2008; 86:182-94. [PMID: 17969052 DOI: 10.1002/jbm.a.31639] [Citation(s) in RCA: 33] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/07/2022]
Abstract
The aim of this study was to develop an easily accessible and reproducible, nonhealing alveolar bone defect in the rabbit mandible. Twenty-four adult male New Zealand white rabbits underwent unilateral mandibular defect surgery. Two types of defect in the premolar/molar region were compared: (1) a 10-mm "full thickness" cylindrical defect removing both cortical plates and the intervening trabecular bone and tooth roots; (2) a 10-mm "partial thickness" cylindrical defect removing only the lateral bony cortex, trabecular bone, and tooth roots. Both types of defect were examined at 0, 8, and 16 weeks using histology and/or microcomputed tomography to determine the quality and quantity of bone formation. The partial thickness defect displayed significant bone fill at 8 weeks (86.9% +/- 10.8%), and complete regeneration of bony contours and bridging by 16 weeks. In contrast, the full thickness defect was never able to bridge itself and displayed no significant difference in bone regeneration between the 8-week (61.5% +/- 3.7%) and 16-week (55.1% +/- 18.5%) time points. These results indicate that a nonhealing defect can be created with a 10-mm bicortical cylindrical ostectomy placed in the premolar/molar region of the rabbit mandible, demonstrating the potential of this animal model as a test bed for mandibular biomaterials and tissue-engineering constructs.
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Affiliation(s)
- Simon Young
- Department of Bioengineering, Rice University, Houston, Texas 77251-1892, USA
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Khan Y, Yaszemski MJ, Mikos AG, Laurencin CT. Tissue engineering of bone: material and matrix considerations. J Bone Joint Surg Am 2008; 90 Suppl 1:36-42. [PMID: 18292355 DOI: 10.2106/jbjs.g.01260] [Citation(s) in RCA: 301] [Impact Index Per Article: 18.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 02/01/2023]
Abstract
When the normal physiologic reaction to fracture does not occur, such as in fracture nonunions or large-scale traumatic bone injury, surgical intervention is warranted. Autografts and allografts represent current strategies for surgical intervention and subsequent bone repair, but each possesses limitations, such as donor-site morbidity with the use of autograft and the risk of disease transmission with the use of allograft. Synthetic bone-graft substitutes, developed in an effort to overcome the inherent limitations of autograft and allograft, represent an alternative strategy. These synthetic graft substitutes, or matrices, are formed from a variety of materials, including natural and synthetic polymers, ceramics, and composites, that are designed to mimic the three-dimensional characteristics of autograft tissue while maintaining viable cell populations. Matrices also act as delivery vehicles for factors, antibiotics, and chemotherapeutic agents, depending on the nature of the injury to be repaired. This intersection of matrices, cells, and therapeutic molecules has collectively been termed tissue engineering. Depending on the specific application of the matrix, certain materials may be more or less well suited to the final structure; these include polymers, ceramics, and composites of the two. Each category is represented by matrices that can form either solid preformed structures or injectable forms that harden in situ. This article discusses the myriad design considerations that are relevant to successful bone repair with tissue-engineered matrices and provides an overview of several manufacturing techniques that allow for the actualization of critical design parameters.
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Affiliation(s)
- Yusuf Khan
- University of Virginia School of Medicine, 400 Ray C. Hunt Drive, Charlottesville, VA 22908, USA
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