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Sinha R, Sanchez A, Camara-Torres M, Uriszar-Aldaca IC, Calore AR, Harings J, Gambardella A, Ciccarelli L, Vanzanella V, Sisani M, Scatto M, Wendelbo R, Perez S, Villanueva S, Matanza A, Patelli A, Grizzuti N, Mota C, Moroni L. Additive Manufactured Scaffolds for Bone Tissue Engineering: Physical Characterization of Thermoplastic Composites with Functional Fillers. ACS APPLIED POLYMER MATERIALS 2021; 3:3788-3799. [PMID: 34476399 PMCID: PMC8397295 DOI: 10.1021/acsapm.1c00363] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 03/18/2021] [Accepted: 07/20/2021] [Indexed: 05/09/2023]
Abstract
Thermoplastic polymer-filler composites are excellent materials for bone tissue engineering (TE) scaffolds, combining the functionality of fillers with suitable load-bearing ability, biodegradability, and additive manufacturing (AM) compatibility of the polymer. Two key determinants of their utility are their rheological behavior in the molten state, determining AM processability and their mechanical load-bearing properties. We report here the characterization of both these physical properties for four bone TE relevant composite formulations with poly(ethylene oxide terephthalate)/poly(butylene terephthalate (PEOT/PBT) as a base polymer, which is often used to fabricate TE scaffolds. The fillers used were reduced graphene oxide (rGO), hydroxyapatite (HA), gentamicin intercalated in zirconium phosphate (ZrP-GTM) and ciprofloxacin intercalated in MgAl layered double hydroxide (MgAl-CFX). The rheological assessment showed that generally the viscous behavior dominated the elastic behavior (G″ > G') for the studied composites, at empirically determined extrusion temperatures. Coupled rheological-thermal characterization of ZrP-GTM and HA composites showed that the fillers increased the solidification temperatures of the polymer melts during cooling. Both these findings have implications for the required extrusion temperatures and bonding between layers. Mechanical tests showed that the fillers generally not only made the polymer stiffer but more brittle in proportion to the filler fractions. Furthermore, the elastic moduli of scaffolds did not directly correlate with the corresponding bulk material properties, implying composite-specific AM processing effects on the mechanical properties. Finally, we show computational models to predict multimaterial scaffold elastic moduli using measured single material scaffold and bulk moduli. The reported characterizations are essential for assessing the AM processability and ultimately the suitability of the manufactured scaffolds for the envisioned bone regeneration application.
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Affiliation(s)
- Ravi Sinha
- MERLN
Institute for Technology-Inspired Regenerative Medicine, Maastricht University, Maastricht 6229 ER, The Netherlands
| | - Alberto Sanchez
- TECNALIA,
Basque Research and Technology Alliance (BRTA), Mikeletegi 2, San Sebastián 20009, Spain
| | - Maria Camara-Torres
- MERLN
Institute for Technology-Inspired Regenerative Medicine, Maastricht University, Maastricht 6229 ER, The Netherlands
| | | | - Andrea Roberto Calore
- MERLN
Institute for Technology-Inspired Regenerative Medicine, Maastricht University, Maastricht 6229 ER, The Netherlands
- Biobased
Materials, Sciences, Chemelot Center, Geleen 6167 RD, The Netherlands
| | - Jules Harings
- Biobased
Materials, Sciences, Chemelot Center, Geleen 6167 RD, The Netherlands
| | | | | | | | | | | | | | - Sergio Perez
- TECNALIA,
Basque Research and Technology Alliance (BRTA), Mikeletegi 2, San Sebastián 20009, Spain
| | - Sara Villanueva
- TECNALIA,
Basque Research and Technology Alliance (BRTA), Mikeletegi 2, San Sebastián 20009, Spain
| | - Amaia Matanza
- Centro
de Fisica de Materiales (CSIC, UPV/EHU), Materials Physics Center (MPC), San Sebastián 20018, Spain
| | - Alessandro Patelli
- Department
of Physics and Astronomy, Padova University, Padova 35131, Italy
| | - Nino Grizzuti
- University
of Naples Federico II, Naples 80125, Italy
| | - Carlos Mota
- MERLN
Institute for Technology-Inspired Regenerative Medicine, Maastricht University, Maastricht 6229 ER, The Netherlands
| | - Lorenzo Moroni
- MERLN
Institute for Technology-Inspired Regenerative Medicine, Maastricht University, Maastricht 6229 ER, The Netherlands
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2
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El Khatib M, Mauro A, Wyrwa R, Di Mattia M, Turriani M, Di Giacinto O, Kretzschmar B, Seemann T, Valbonetti L, Berardinelli P, Schnabelrauch M, Barboni B, Russo V. Fabrication and Plasma Surface Activation of Aligned Electrospun PLGA Fiber Fleeces with Improved Adhesion and Infiltration of Amniotic Epithelial Stem Cells Maintaining their Teno-inductive Potential. Molecules 2020; 25:E3176. [PMID: 32664582 PMCID: PMC7396982 DOI: 10.3390/molecules25143176] [Citation(s) in RCA: 12] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/08/2020] [Revised: 07/06/2020] [Accepted: 07/09/2020] [Indexed: 02/06/2023] Open
Abstract
Electrospun PLGA microfibers with adequate intrinsic physical features (fiber alignment and diameter) have been shown to boost teno-differentiation and may represent a promising solution for tendon tissue engineering. However, the hydrophobic properties of PLGA may be adjusted through specific treatments to improve cell biodisponibility. In this study, electrospun PLGA with highly aligned microfibers were cold atmospheric plasma (CAP)-treated by varying the treatment exposure time (30, 60, and 90 s) and the working distance (1.3 and 1.7 cm) and characterized by their physicochemical, mechanical and bioactive properties on ovine amniotic epithelial cells (oAECs). CAP improved the hydrophilic properties of the treated materials due to the incorporation of new oxygen polar functionalities on the microfibers' surface especially when increasing treatment exposure time and lowering working distance. The mechanical properties, though, were affected by the treatment exposure time where the optimum performance was obtained after 60 s. Furthermore, CAP treatment did not alter oAECs' biocompatibility and improved cell adhesion and infiltration onto the microfibers especially those treated from a distance of 1.3 cm. Moreover, teno-inductive potential of highly aligned PLGA electrospun microfibers was maintained. Indeed, cells cultured onto the untreated and CAP treated microfibers differentiated towards the tenogenic lineage expressing tenomodulin, a mature tendon marker, in their cytoplasm. In conclusion, CAP treatment on PLGA microfibers conducted at 1.3 cm working distance represent the optimum conditions to activate PLGA surface by improving their hydrophilicity and cell bio-responsiveness. Since for tendon tissue engineering purposes, both high cell adhesion and mechanical parameters are crucial, PLGA treated for 60 s at 1.3 cm was identified as the optimal construct.
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Affiliation(s)
- Mohammad El Khatib
- Unit of Basic and Applied Biosciences, Faculty of Bioscience and Agro-Food and Environmental Technology, University of Teramo, 64100 Teramo, Italy; (M.E.K.); (M.D.M.); (M.T.); (O.D.G.); (L.V.); (P.B.); (B.B.); (V.R.)
| | - Annunziata Mauro
- Unit of Basic and Applied Biosciences, Faculty of Bioscience and Agro-Food and Environmental Technology, University of Teramo, 64100 Teramo, Italy; (M.E.K.); (M.D.M.); (M.T.); (O.D.G.); (L.V.); (P.B.); (B.B.); (V.R.)
| | - Ralf Wyrwa
- Department of Biomaterials, INNOVENT e. V., 07745 Jena, Germany; (R.W.); (M.S.)
| | - Miriam Di Mattia
- Unit of Basic and Applied Biosciences, Faculty of Bioscience and Agro-Food and Environmental Technology, University of Teramo, 64100 Teramo, Italy; (M.E.K.); (M.D.M.); (M.T.); (O.D.G.); (L.V.); (P.B.); (B.B.); (V.R.)
| | - Maura Turriani
- Unit of Basic and Applied Biosciences, Faculty of Bioscience and Agro-Food and Environmental Technology, University of Teramo, 64100 Teramo, Italy; (M.E.K.); (M.D.M.); (M.T.); (O.D.G.); (L.V.); (P.B.); (B.B.); (V.R.)
| | - Oriana Di Giacinto
- Unit of Basic and Applied Biosciences, Faculty of Bioscience and Agro-Food and Environmental Technology, University of Teramo, 64100 Teramo, Italy; (M.E.K.); (M.D.M.); (M.T.); (O.D.G.); (L.V.); (P.B.); (B.B.); (V.R.)
| | - Björn Kretzschmar
- Department of Surface Engineering, INNOVENT e. V., 07745 Jena, Germany; (B.K.); (T.S.)
| | - Thomas Seemann
- Department of Surface Engineering, INNOVENT e. V., 07745 Jena, Germany; (B.K.); (T.S.)
| | - Luca Valbonetti
- Unit of Basic and Applied Biosciences, Faculty of Bioscience and Agro-Food and Environmental Technology, University of Teramo, 64100 Teramo, Italy; (M.E.K.); (M.D.M.); (M.T.); (O.D.G.); (L.V.); (P.B.); (B.B.); (V.R.)
| | - Paolo Berardinelli
- Unit of Basic and Applied Biosciences, Faculty of Bioscience and Agro-Food and Environmental Technology, University of Teramo, 64100 Teramo, Italy; (M.E.K.); (M.D.M.); (M.T.); (O.D.G.); (L.V.); (P.B.); (B.B.); (V.R.)
| | | | - Barbara Barboni
- Unit of Basic and Applied Biosciences, Faculty of Bioscience and Agro-Food and Environmental Technology, University of Teramo, 64100 Teramo, Italy; (M.E.K.); (M.D.M.); (M.T.); (O.D.G.); (L.V.); (P.B.); (B.B.); (V.R.)
| | - Valentina Russo
- Unit of Basic and Applied Biosciences, Faculty of Bioscience and Agro-Food and Environmental Technology, University of Teramo, 64100 Teramo, Italy; (M.E.K.); (M.D.M.); (M.T.); (O.D.G.); (L.V.); (P.B.); (B.B.); (V.R.)
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3
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Carrow JK, Di Luca A, Dolatshahi-Pirouz A, Moroni L, Gaharwar AK. 3D-printed bioactive scaffolds from nanosilicates and PEOT/PBT for bone tissue engineering. Regen Biomater 2019; 6:29-37. [PMID: 30740240 PMCID: PMC6362822 DOI: 10.1093/rb/rby024] [Citation(s) in RCA: 25] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/18/2018] [Revised: 09/08/2018] [Accepted: 10/08/2018] [Indexed: 12/20/2022] Open
Abstract
Additive manufacturing (AM) has shown promise in designing 3D scaffold for regenerative medicine. However, many synthetic biomaterials used for AM are bioinert. Here, we report synthesis of bioactive nanocomposites from a poly(ethylene oxide terephthalate) (PEOT)/poly(butylene terephthalate) (PBT) (PEOT/PBT) copolymer and 2D nanosilicates for fabricating 3D scaffolds for bone tissue engineering. PEOT/PBT have been shown to support calcification and bone bonding ability in vivo, while 2D nanosilicates induce osteogenic differentiation of human mesenchymal stem cells (hMSCs) in absence of osteoinductive agents. The effect of nanosilicates addition to PEOT/PBT on structural, mechanical and biological properties is investigated. Specifically, the addition of nanosilicate to PEOT/PBT improves the stability of nanocomposites in physiological conditions, as nanosilicate suppressed the degradation rate of copolymer. However, no significant increase in the mechanical stiffness of scaffold due to the addition of nanosilicates is observed. The addition of nanosilicates to PEOT/PBT improves the bioactive properties of AM nanocomposites as demonstrated in vitro. hMSCs readily proliferated on the scaffolds containing nanosilicates and resulted in significant upregulation of osteo-related proteins and production of mineralized matrix. The synergistic ability of nanosilicates and PEOT/PBT can be utilized for designing bioactive scaffolds for bone tissue engineering.
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Affiliation(s)
- James K Carrow
- Department of Biomedical Engineering, Texas A&M University, College Station, TX, USA
| | - Andrea Di Luca
- Tissue Regeneration Department, MIRA Institute for Biomedical Technology and Technical Medicine, University of Twente, Enschede, The Netherlands
| | - Alireza Dolatshahi-Pirouz
- DTU Nanotech, Center for Intestinal Absorption and Transport of Biopharmaceuticals, Technical University of Denmark, 2800 Kgs, Lyngby, Denmark
| | - Lorenzo Moroni
- Tissue Regeneration Department, MIRA Institute for Biomedical Technology and Technical Medicine, University of Twente, Enschede, The Netherlands
- Department of Complex Tissue Regeneration, MERLN Institute for Technology-Inspired Regenerative Medicine, Maastricht University, Universiteitsingel 40, Maastricht, The Netherlands
| | - Akhilesh K Gaharwar
- Department of Biomedical Engineering, Texas A&M University, College Station, TX, USA
- Department of Materials Science, Texas A&M University, College Station, TX, USA and
- Center for Remote Health Technologies and Systems, Texas A&M University, College Station, TX, USA
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4
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Cai J, Yang Y, Ai C, Jin W, Sheng D, Chen J, Chen S. Bone Marrow Stem Cells-Seeded Polyethylene Terephthalate Scaffold in Repair and Regeneration of Rabbit Achilles Tendon. Artif Organs 2018; 42:1086-1094. [PMID: 30294929 DOI: 10.1111/aor.13298] [Citation(s) in RCA: 12] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/12/2018] [Revised: 05/11/2018] [Accepted: 05/25/2018] [Indexed: 12/16/2022]
Abstract
The objective of this study was to evaluate the effect of bone marrow stem cells (BMSCs)-seeded polyethylene terephthalate (PET) scaffold for Achilles tendon repair in a rabbit model. The allogeneic BMSCs were seeded onto the PET scaffold and cultured in vitro for 14 days. Sixteen mature New Zealand rabbits underwent surgery to establish a 2-cm Achilles tendon defect model. The BMSCs-seeded PET scaffold was implanted into the defect of one limb (BMSCs-PET group), while the PET scaffold without BMSCs was implanted into the defect of contralateral limb as the control (PET group). All rabbits were sacrificed at 6 and 12 weeks after surgery. At 12 weeks after surgery, macroscopic and histological results showed formation of tendon-like tissues, and the structure was more mature in the BMSCs-PET group. Immunohistochemical analysis and real-time polymerase chain reaction (RT-PCR) demonstrated that the collagen I and collagen III were significantly higher in the BMSCs-PET group compared with those in the PET group. Mechanically, both the failure load and the average stiffness were significantly higher in the BMSCs-PET group than those in the PET group. In conclusion, BMSCs-seeded PET scaffold could effectively facilitate the healing process after being implanted in a rabbit Achilles tendon defect model.
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Affiliation(s)
- Jiangyu Cai
- Department of Sports Medicine, Huashan Hospital, Fudan University, Shanghai, P.R. China
| | - Yimeng Yang
- Department of Sports Medicine, Huashan Hospital, Fudan University, Shanghai, P.R. China
| | - Chengchong Ai
- Department of Sports Medicine, Huashan Hospital, Fudan University, Shanghai, P.R. China
| | - Wenhe Jin
- Department of Sports Medicine, Huashan Hospital, Fudan University, Shanghai, P.R. China
| | - Dandan Sheng
- Department of Sports Medicine, Huashan Hospital, Fudan University, Shanghai, P.R. China
| | - Jun Chen
- Department of Sports Medicine, Huashan Hospital, Fudan University, Shanghai, P.R. China
| | - Shiyi Chen
- Department of Sports Medicine, Huashan Hospital, Fudan University, Shanghai, P.R. China
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5
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Kumar A, Mahendra J, Samuel S, Govindraj J, Loganathan T, Vashum Y, Mahendra L, Krishnamoorthy T. Platelet-rich fibrin/biphasic calcium phosphate impairs osteoclast differentiation and promotes apoptosis by the intrinsic mitochondrial pathway in chronic periodontitis. J Periodontol 2018; 90:61-71. [DOI: 10.1002/jper.17-0306] [Citation(s) in RCA: 13] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/13/2017] [Revised: 09/08/2017] [Accepted: 02/10/2018] [Indexed: 12/21/2022]
Affiliation(s)
- Anil Kumar
- Department of Periodontics; Meenakshi Ammal Dental College and Hospital; Chennai India
| | - Jaideep Mahendra
- Department of Periodontics; Meenakshi Ammal Dental College and Hospital; Chennai India
| | - Shila Samuel
- Department of Biochemistry; VRR Institute of Biomedical Science (Affiliated to University of Madras); Chennai India
| | - Jayamathi Govindraj
- Department of Biochemistry; Meenakshi Ammal Dental College and Hospital; Chennai India
| | - Tholcopiyan Loganathan
- Department of Biochemistry; VRR Institute of Biomedical Science (Affiliated to University of Madras); Chennai India
| | - Yaongamphi Vashum
- Department of Biochemistry; VRR Institute of Biomedical Science (Affiliated to University of Madras); Chennai India
| | - Little Mahendra
- Department of Periodontics; Annamalai University; Annamalai Nagar Chidambaram Tamilnadu India
| | - Thiagarajan Krishnamoorthy
- Department of Biochemistry; VRR Institute of Biomedical Science (Affiliated to University of Madras); Chennai India
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6
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Bouler J, Pilet P, Gauthier O, Verron E. Biphasic calcium phosphate ceramics for bone reconstruction: A review of biological response. Acta Biomater 2017; 53:1-12. [PMID: 28159720 DOI: 10.1016/j.actbio.2017.01.076] [Citation(s) in RCA: 241] [Impact Index Per Article: 34.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/28/2016] [Revised: 01/04/2017] [Accepted: 01/27/2017] [Indexed: 12/23/2022]
Abstract
Autologous bone graft is considered as the gold standard in bone reconstructive surgery. However, the quantity of bone available is limited and the harvesting procedure requires a second surgical site resulting in severe complications. Due to these limits, scientists and clinicians have considered alternatives to autologous bone graft. Calcium phosphates (CaPs) biomaterials including biphasic calcium phosphate (BCP) ceramics have proven efficacy in numerous clinical indications. Their specific physico-chemical properties (HA/TCP ratio, dual porosity and subsequent interconnected architecture) control (regulate/condition) the progressive resorption and the bone substitution process. By describing the most significant biological responses reported in the last 30years, we review the main events that made their clinical success. We also discuss about their exciting future applications as osteoconductive scaffold for delivering various bioactive molecules or bone cells in bone tissue engineering and regenerative medicine. STATEMENT OF SIGNIFICANCE Nowadays, BCPs are definitely considered as the gold standard of bone substitutes in bone reconstructive surgery. Among the numerous clinical studies in literature demonstrating the performance of BCP, Passuti et al. and Randsford et al. studies largely contributed to the emergence of the BCPs. It could be interesting to come back to the main events that made their success and could explain their large adhesion from scientists to clinicians. This paper aims to review the most significant biological responses reported in the last 30years, of these BCP-based materials. We also discuss about their exciting future applications as osteoconductive scaffold for delivering various bioactive molecules or bone cells in bone tissue engineering and regenerative medicine.
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Hardy JG, Torres-Rendon JG, Leal-Egaña A, Walther A, Schlaad H, Cölfen H, Scheibel TR. Biomineralization of Engineered Spider Silk Protein-Based Composite Materials for Bone Tissue Engineering. MATERIALS (BASEL, SWITZERLAND) 2016; 9:E560. [PMID: 28773681 PMCID: PMC5456849 DOI: 10.3390/ma9070560] [Citation(s) in RCA: 25] [Impact Index Per Article: 3.1] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 03/01/2016] [Revised: 06/06/2016] [Accepted: 06/24/2016] [Indexed: 01/26/2023]
Abstract
Materials based on biodegradable polyesters, such as poly(butylene terephthalate) (PBT) or poly(butylene terephthalate-co-poly(alkylene glycol) terephthalate) (PBTAT), have potential application as pro-regenerative scaffolds for bone tissue engineering. Herein, the preparation of films composed of PBT or PBTAT and an engineered spider silk protein, (eADF4(C16)), that displays multiple carboxylic acid moieties capable of binding calcium ions and facilitating their biomineralization with calcium carbonate or calcium phosphate is reported. Human mesenchymal stem cells cultured on films mineralized with calcium phosphate show enhanced levels of alkaline phosphatase activity suggesting that such composites have potential use for bone tissue engineering.
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Affiliation(s)
- John G Hardy
- Lehrstuhl Biomaterialien, Universität Bayreuth, Universitätsstraße 30, Bayreuth 95447, Germany.
| | | | - Aldo Leal-Egaña
- Lehrstuhl Biomaterialien, Universität Bayreuth, Universitätsstraße 30, Bayreuth 95447, Germany.
| | - Andreas Walther
- DWI Leibniz Institute for Interactive Materials, Forckenbeckstr. 50, Aachen 52056, Germany.
| | - Helmut Schlaad
- Institute of Chemistry, University of Potsdam, Karl-Liebknecht-Str. 24-25, Potsdam 14476, Germany.
| | - Helmut Cölfen
- Physical Chemistry, Department of Chemistry, University of Konstanz, Universitätsstr. 10, Konstanz D-78457, Germany.
| | - Thomas R Scheibel
- Lehrstuhl Biomaterialien, Universität Bayreuth, Universitätsstraße 30, Bayreuth 95447, Germany.
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Leferink AM, Chng YC, van Blitterswijk CA, Moroni L. Distribution and Viability of Fetal and Adult Human Bone Marrow Stromal Cells in a Biaxial Rotating Vessel Bioreactor after Seeding on Polymeric 3D Additive Manufactured Scaffolds. Front Bioeng Biotechnol 2015; 3:169. [PMID: 26557644 PMCID: PMC4617101 DOI: 10.3389/fbioe.2015.00169] [Citation(s) in RCA: 15] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Key Words] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/30/2015] [Accepted: 10/08/2015] [Indexed: 12/28/2022] Open
Abstract
One of the conventional approaches in tissue engineering is the use of scaffolds in combination with cells to obtain mechanically stable tissue constructs in vitro prior to implantation. Additive manufacturing by fused deposition modeling is a widely used technique to produce porous scaffolds with defined pore network, geometry, and therewith defined mechanical properties. Bone marrow-derived mesenchymal stromal cells (MSCs) are promising candidates for tissue engineering-based cell therapies due to their multipotent character. One of the hurdles to overcome when combining additive manufactured scaffolds with MSCs is the resulting heterogeneous cell distribution and limited cell proliferation capacity. In this study, we show that the use of a biaxial rotating bioreactor, after static culture of human fetal MSCs (hfMSCs) seeded on synthetic polymeric scaffolds, improved the homogeneity of cell and extracellular matrix distribution and increased the total cell number. Furthermore, we show that the relative mRNA expression levels of indicators for stemness and differentiation are not significantly changed upon this bioreactor culture, whereas static culture shows variations of several indicators for stemness and differentiation. The biaxial rotating bioreactor presented here offers a homogeneous distribution of hfMSCs, enabling studies on MSCs fate in additive manufactured scaffolds without inducing undesired differentiation.
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Affiliation(s)
- Anne M Leferink
- Department of Tissue Regeneration, MIRA Institute, University of Twente , Enschede , Netherlands ; Department of Complex Tissue Regeneration, Faculty of Health, Medicine and Life Sciences, Maastricht University , Maastricht , Netherlands
| | | | - Clemens A van Blitterswijk
- Department of Tissue Regeneration, MIRA Institute, University of Twente , Enschede , Netherlands ; Department of Complex Tissue Regeneration, Faculty of Health, Medicine and Life Sciences, Maastricht University , Maastricht , Netherlands
| | - Lorenzo Moroni
- Department of Tissue Regeneration, MIRA Institute, University of Twente , Enschede , Netherlands ; Department of Complex Tissue Regeneration, Faculty of Health, Medicine and Life Sciences, Maastricht University , Maastricht , Netherlands
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9
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Effects of Artificial Ligaments with Different Porous Structures on the Migration of BMSCs. Stem Cells Int 2015; 2015:702381. [PMID: 26106429 PMCID: PMC4464596 DOI: 10.1155/2015/702381] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/14/2015] [Revised: 03/31/2015] [Accepted: 03/31/2015] [Indexed: 01/28/2023] Open
Abstract
Polyethylene terephthalate- (PET-) based artificial ligaments (PET-ALs) are commonly used in anterior cruciate ligament (ACL) reconstruction surgery. The effects of different porous structures on the migration of bone marrow mesenchymal stem cells (BMSCs) on artificial ligaments and the underlying mechanisms are unclear. In this study, a cell migration model was utilized to observe the migration of BMSCs on PET-ALs with different porous structures. A rabbit extra-articular graft-to-bone healing model was applied to investigate the in vivo effects of four types of PET-ALs, and a mechanical test and histological observation were performed at 4 weeks and 12 weeks. The BMSC migration area of the 5A group was significantly larger than that of the other three groups. The migration of BMSCs in the 5A group was abolished by blocking the RhoA/ROCK signaling pathway with Y27632. The in vivo study demonstrated that implantation of 5A significantly improved osseointegration. Our study explicitly demonstrates that the migration ability of BMSCs can be regulated by varying the porous structures of the artificial ligaments and suggests that this regulation is related to the RhoA/ROCK signaling pathway. Artificial ligaments prepared using a proper knitting method and line density may exhibit improved biocompatibility and clinical performance.
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10
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Rongen JJ, van Tienen TG, van Bochove B, Grijpma DW, Buma P. Biomaterials in search of a meniscus substitute. Biomaterials 2014; 35:3527-40. [DOI: 10.1016/j.biomaterials.2014.01.017] [Citation(s) in RCA: 79] [Impact Index Per Article: 7.9] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/17/2013] [Accepted: 01/08/2014] [Indexed: 11/24/2022]
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11
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Pedersen TO, Blois AL, Xing Z, Xue Y, Sun Y, Finne-Wistrand A, Akslen LA, Lorens JB, Leknes KN, Fristad I, Mustafa K. Endothelial microvascular networks affect gene-expression profiles and osteogenic potential of tissue-engineered constructs. Stem Cell Res Ther 2013; 4:52. [PMID: 23683577 PMCID: PMC3706836 DOI: 10.1186/scrt202] [Citation(s) in RCA: 33] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/05/2012] [Accepted: 05/14/2013] [Indexed: 01/07/2023] Open
Abstract
Introduction A major determinant of the potential size of cell/scaffold constructs in tissue engineering is vascularization. The aims of this study were twofold: first to determine the in vitro angiogenic and osteogenic gene-expression profiles of endothelial cells (ECs) and mesenchymal stem cells (MSCs) cocultured in a dynamic 3D environment; and second, to assess differentiation and the potential for osteogenesis after in vivo implantation. Methods MSCs and ECs were grown in dynamic culture in poly(L-lactide-co-1,5-dioxepan-2-one) (poly(LLA-co-DXO)) copolymer scaffolds for 1 week, to generate three-dimensional endothelial microvascular networks. The constructs were then implanted in vivo, in a murine model for ectopic bone formation. Expression of selected genes for angiogenesis and osteogenesis was studied after a 1-week culture in vitro. Human cell proliferation was assessed as expression of ki67, whereas α-smooth muscle actin was used to determine the perivascular differentiation of MSCs. Osteogenesis was evaluated in vivo through detection of selected markers, by using real-time RT-PCR, alkaline phosphatase (ALP), Alizarin Red, hematoxylin/eosin (HE), and Masson trichrome staining. Results The results show that endothelial microvascular networks could be generated in a poly(LLA-co-DXO) scaffold in vitro and sustained after in vivo implantation. The addition of ECs to MSCs influenced both angiogenic and osteogenic gene-expression profiles. Furthermore, human ki67 was upregulated before and after implantation. MSCs could support functional blood vessels as perivascular cells independent of implanted ECs. In addition, the expression of ALP was upregulated in the presence of endothelial microvascular networks. Conclusions This study demonstrates that copolymer poly(LLA-co-DXO) scaffolds can be prevascularized with ECs and MSCs. Although a local osteoinductive environment is required to achieve ectopic bone formation, seeding of MSCs with or without ECs increases the osteogenic potential of tissue-engineered constructs.
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12
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Nguyen LH, Annabi N, Nikkhah M, Bae H, Binan L, Park S, Kang Y, Yang Y, Khademhosseini A. Vascularized bone tissue engineering: approaches for potential improvement. TISSUE ENGINEERING PART B-REVIEWS 2012; 18:363-82. [PMID: 22765012 DOI: 10.1089/ten.teb.2012.0012] [Citation(s) in RCA: 203] [Impact Index Per Article: 16.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 12/23/2022]
Abstract
Significant advances have been made in bone tissue engineering (TE) in the past decade. However, classical bone TE strategies have been hampered mainly due to the lack of vascularization within the engineered bone constructs, resulting in poor implant survival and integration. In an effort toward clinical success of engineered constructs, new TE concepts have arisen to develop bone substitutes that potentially mimic native bone tissue structure and function. Large tissue replacements have failed in the past due to the slow penetration of the host vasculature, leading to necrosis at the central region of the engineered tissues. For this reason, multiple microscale strategies have been developed to induce and incorporate vascular networks within engineered bone constructs before implantation in order to achieve successful integration with the host tissue. Previous attempts to engineer vascularized bone tissue only focused on the effect of a single component among the three main components of TE (scaffold, cells, or signaling cues) and have only achieved limited success. However, with efforts to improve the engineered bone tissue substitutes, bone TE approaches have become more complex by combining multiple strategies simultaneously. The driving force behind combining various TE strategies is to produce bone replacements that more closely recapitulate human physiology. Here, we review and discuss the limitations of current bone TE approaches and possible strategies to improve vascularization in bone tissue substitutes.
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Affiliation(s)
- Lonnissa H Nguyen
- Harvard-MIT Division of Health Sciences and Technology, Massachusetts Institute of Technology, Cambridge, Massachusetts 02139, USA
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Saito E, Liao EE, Hu WW, Krebsbach PH, Hollister SJ. Effects of designed PLLA and 50:50 PLGA scaffold architectures on bone formation in vivo. J Tissue Eng Regen Med 2011; 7:99-111. [PMID: 22162220 DOI: 10.1002/term.497] [Citation(s) in RCA: 42] [Impact Index Per Article: 3.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/15/2010] [Revised: 03/02/2011] [Accepted: 07/12/2011] [Indexed: 11/05/2022]
Abstract
Biodegradable porous scaffolds have been investigated as an alternative approach to current metal, ceramic, and polymer bone graft substitutes for lost or damaged bone tissues. Although there have been many studies investigating the effects of scaffold architecture on bone formation, many of these scaffolds were fabricated using conventional methods such as salt leaching and phase separation, and were constructed without designed architecture. To study the effects of both designed architecture and material on bone formation, this study designed and fabricated three types of porous scaffold architecture from two biodegradable materials, poly (L-lactic acid) (PLLA) and 50:50 Poly(lactic-co-glycolic acid) (PLGA), using image based design and indirect solid freeform fabrication techniques, seeded them with bone morphogenetic protein-7 transduced human gingival fibroblasts, and implanted them subcutaneously into mice for 4 and 8 weeks. Micro-computed tomography data confirmed that the fabricated porous scaffolds replicated the designed architectures. Histological analysis revealed that the 50:50 PLGA scaffolds degraded but did not maintain their architecture after 4 weeks implantation. However, PLLA scaffolds maintained their architecture at both time points and showed improved bone ingrowth, which followed the internal architecture of the scaffolds. Mechanical properties of both PLLA and 50:50 PLGA scaffolds decreased but PLLA scaffolds maintained greater mechanical properties than 50:50 PLGA after implantation. The increase of mineralized tissue helped support the mechanical properties of bone tissue and scaffold constructs between 4-8 weeks. The results indicate the importance of choice of scaffold materials and computationally designed scaffolds to control tissue formation and mechanical properties for desired bone tissue regeneration.
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Affiliation(s)
- Eiji Saito
- Department of Biomedical Engineering, University of Michigan, Ann Arbor, Michigan 48109-2099, 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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15
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Evaluation of tubular poly(trimethylene carbonate) tissue engineering scaffolds in a circulating pulsatile flow system. Int J Artif Organs 2011; 34:161-71. [PMID: 21374572 DOI: 10.5301/ijao.2011.6396] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Accepted: 12/13/2010] [Indexed: 11/20/2022]
Abstract
Tubular scaffolds (internal diameter approximately 3 mm and wall thickness approximately 0.8 mm) with a porosity of approximately 83% and an average pore size of 116 µm were prepared from flexible poly(trimethylene carbonate) (PTMC) polymer by dip-coating and particulate leaching methods. PTMC is a flexible and biocompatible polymer that crosslinks upon irradiation; porous network structures were obtained by irradiating the specimens in vacuum at 25 kGy before leaching soluble salt particles. To assess the suitability of these scaffolds in dynamic cell culturing for cardiovascular tissue engineering, the scaffolds were coated with a thin (0.1 to 0.2 mm) non-porous PTMC layer and its performance was evaluated in a closed pulsatile flow system (PFS). For this, the PFS was operated at physiological conditions at liquid flows of 1.56 ml/s with pressures varying from 80-120 mmHg at a frequency of 70 pulsations per minute. The mechanical properties of these coated porous PTMC scaffolds were not significantly different than non-coated scaffolds. Typical tensile strengths in the radial direction were 0.15 MPa, initial stiffness values were close to 1.4 MPa. Their creep resistance in cyclic deformation experiments was excellent. In the pulsatile flow setup, the distention rates of these flexible and elastic scaffolds were approximately 0.10% per mmHg, which is comparable to that of a porcine carotid artery (0.11% per mmHg). The compliance and stiffness index values were close to those of natural arteries.?In long-term deformation studies, where the scaffolds were subjected to physiological pulsatile pressures for one week, the morphology and mechanical properties of the PTMC scaffolds did not change. This suggests their suitability for application in a dynamic cell culture bioreactor.
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Obenaus A, Hayes P. Drill hole defects: induction, imaging, and analysis in the rodent. Methods Mol Biol 2011; 690:301-14. [PMID: 21043001 DOI: 10.1007/978-1-60761-962-8_20] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/19/2023]
Abstract
Advances in stem therapy, scaffolds, and therapeutic biomolecules are accelerating bone repair research, and model systems are required to test new methods and concepts. The drill hole defect is one such model and is used to study a variety of bone defects and potential therapies designed to repair these injuries. We detail the methodologies required to successfully generate and evaluate drill hole defects. Although performing a successful drill hole defect requires patience and dexterity, investing the time to perfect the technique will provide ample opportunity for the researcher to expand his/her particular research interests. Mastering this technique will allow testing of stem cell therapies, novel scaffold designs, and biomolecules that can be used for clinical translation.
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Affiliation(s)
- Andre Obenaus
- Non-Invasive Imaging Laboratory, School of Medicine, Loma Linda University, Loma Linda, CA, USA.
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17
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Tzeranis DS, Roy A, So PTC, Yannas IV. An optical method to quantify the density of ligands for cell adhesion receptors in three-dimensional matrices. J R Soc Interface 2010; 7 Suppl 5:S649-61. [PMID: 20671067 PMCID: PMC3024575 DOI: 10.1098/rsif.2010.0321.focus] [Citation(s) in RCA: 10] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/14/2010] [Accepted: 07/09/2010] [Indexed: 12/21/2022] Open
Abstract
The three-dimensional matrix that surrounds cells is an important insoluble regulator of cell phenotypes. Examples of such insoluble surfaces are the extracellular matrix (ECM), ECM analogues and synthetic polymeric biomaterials. Cell-matrix interactions are mediated by cell adhesion receptors that bind to chemical entities (adhesion ligands) on the surface of the matrix. There are currently no established methods to obtain quantitative estimates of the density of adhesion ligands recognized by specific cell adhesion receptors. This article presents a new optical-based methodology for measuring ligands of adhesion receptors on three-dimensional matrices. The study also provides preliminary quantitative results for the density of adhesion ligands of integrins alpha(1)beta(1) and alpha(2)beta(1) on the surface of collagen-based scaffolds, similar to biomaterials that are used clinically to induce regeneration in injured skin and peripheral nerves. Preliminary estimates of the surface density of the ligands of these two major collagen-binding receptors are 5775 +/- 2064 ligands microm(-2) for ligands of alpha(1)beta(1) and 17 084 +/- 5353 ligands microm(-2) for ligands of alpha(2)beta(1). The proposed methodology can be used to quantify the surface chemistry of insoluble surfaces that possess biological activity, such as native tissue ECM and biomaterials, and therefore can be used in cell biology, biomaterials science and regenerative medical studies for quantitative description of a matrix and its effects on cells.
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Affiliation(s)
- Dimitrios S. Tzeranis
- Department of Mechanical Engineering, Massachusetts Institute of Technology, Cambridge, MA 02139, USA
| | - Amit Roy
- Department of Mechanical Engineering, Massachusetts Institute of Technology, Cambridge, MA 02139, USA
- Department of Ophthalmology, University of Massachusetts Medical School, Worcester, MA 01655, USA
| | - Peter T. C. So
- Department of Mechanical Engineering, Massachusetts Institute of Technology, Cambridge, MA 02139, USA
- Department of Biological Engineering, Massachusetts Institute of Technology, Cambridge, MA 02139, USA
| | - Ioannis V. Yannas
- Department of Mechanical Engineering, Massachusetts Institute of Technology, Cambridge, MA 02139, USA
- Department of Biological Engineering, Massachusetts Institute of Technology, Cambridge, MA 02139, USA
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Song Y, Wennink JWH, Kamphuis MMJ, Vermes I, Poot AA, Feijen J, Grijpma DW. Effective seeding of smooth muscle cells into tubular poly(trimethylene carbonate) scaffolds for vascular tissue engineering. J Biomed Mater Res A 2010; 95:440-6. [DOI: 10.1002/jbm.a.32859] [Citation(s) in RCA: 25] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/10/2022]
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19
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Geffre CP, Margolis DS, Ruth JT, DeYoung DW, Tellis BC, Szivek JA. A novel biomimetic polymer scaffold design enhances bone ingrowth. J Biomed Mater Res A 2010; 91:795-805. [PMID: 19051300 DOI: 10.1002/jbm.a.32251] [Citation(s) in RCA: 14] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/08/2022]
Abstract
There has been recent interest in treating large bone defects with polymer scaffolds because current modalities such as autographs and allographs have limitations. Additionally, polymer scaffolds are utilized in tissue engineering applications to implant and anchor tissues in place, promoting integration with surrounding native tissue. In both applications, rapid and increased bone growth is crucial to the success of the implant. Recent studies have shown that mimicking native bone tissue morphology leads to increased osteoblastic phenotype and more rapid mineralization. The purpose of this study was to compare bone ingrowth into polymer scaffolds created with a biomimetic porous architecture to those with a simple porous design. The biomimetic architecture was designed from the inverse structure of native trabecular bone and manufactured using solid free form fabrication. Histology and muCT analysis demonstrated a 500-600% increase in bone growth into and adjacent to the biomimetic scaffold at five months post-op. This is in agreement with previous studies in which biomimetic approaches accelerated bone formation. It also supports the applicability of polymer scaffolds for the treatment of large tissue defects when implanting tissue-engineering constructs. (c) 2008 Wiley Periodicals, Inc. J Biomed Mater Res, 2009.
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Affiliation(s)
- Chris P Geffre
- Department of Orthopaedic Surgery, Orthopaedic Research Laboratory, University of Arizona, Tucson, Arizona, USA.
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Schliephake H, Zghoul N, Jäger V, van Griensven M, Zeichen J, Gelinsky M, Wülfing T. Effect of seeding technique and scaffold material on bone formation in tissue-engineered constructs. J Biomed Mater Res A 2009; 90:429-37. [PMID: 18523951 DOI: 10.1002/jbm.a.32104] [Citation(s) in RCA: 20] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/08/2022]
Abstract
The aim of the present study was to test the hypothesis that both scaffold material and the type of cell culturing contribute to the results of in vivo osteogenesis in tissue-engineered constructs in an interactive manner. CaCO3 scaffolds and mineralized collagen scaffolds were seeded with human trabecular bone cells at a density of 5 x 10(6) cells/cm(3) and were left to attach under standard conditions for 24 h. Subsequently, they were submitted to static and dynamic culturing for 14 days (groups III and IV, respectively). Dynamic culturing was carried out in a continuous flow perfusion bioreactor. Empty scaffolds and scaffolds that were seeded with cells and kept under standard conditions for 24 h served as controls (groups I and II, respectively). Five scaffolds of each biomaterial and from each group were implanted into the gluteal muscles of rnu rats for 6 weeks. Osteogenesis was assessed quantitatively by histomorphometry and expression of osteocalcin (OC) and vascular endothelial growth factor (VEGF) was determined by immunohistochemistry. CaCO3 scaffolds exhibited 15.8% (SD 3.1) of newly formed bone after static culture and 22.4% (SD 8.2) after dynamic culture. Empty control scaffolds did not show bone formation, and scaffolds after 24 h of standard conditions produced 8.2% of newly formed bone (SD 4.0). Differences between the controls and the scaffolds cultured for 14 days were significant, but there was no significant difference between static and dynamic culturing. Mineralized collagen scaffolds did not show bone formation in any group. There was a significant difference in the expression of OC within the scaffolds submitted to static versus dynamic culturing in the CaCO3 scaffolds. VEGF expression did not show significant differences between static and dynamic culturing in the two biomaterials tested. It is concluded that within the limitations of the study the type of biomaterial had the dominant effect on in vivo bone formation in small tissue-engineered scaffolds. The culture period additionally affected the amount of bone formed, whereas the type of culturing may have had a positive effect on the expression of osteogenic markers but not on the quantity of bone formation.
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Affiliation(s)
- H Schliephake
- Department of Oral and Maxillofacial Surgery, George-Augusta-University, Göttingen, Germany.
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Long-term bone tissue reaction to polyethylene oxide/polybutylene terephthalate copolymer (Polyactive®) in metacarpophalangeal joint reconstruction. Biomaterials 2008; 29:2509-15. [DOI: 10.1016/j.biomaterials.2008.02.013] [Citation(s) in RCA: 23] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/08/2007] [Accepted: 02/13/2008] [Indexed: 11/21/2022]
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Dawson JI, Oreffo ROC. Bridging the regeneration gap: stem cells, biomaterials and clinical translation in bone tissue engineering. Arch Biochem Biophys 2008; 473:124-31. [PMID: 18396145 DOI: 10.1016/j.abb.2008.03.024] [Citation(s) in RCA: 100] [Impact Index Per Article: 6.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/07/2008] [Revised: 03/20/2008] [Accepted: 03/21/2008] [Indexed: 12/20/2022]
Abstract
Advances in our understanding of skeletal stem cells and their role in bone development and repair, offer the potential to open new frontiers in bone regeneration. Tissue engineering seeks to harness the regenerative capacity innate to bone for the replacement of tissue lost or damaged through a broad range of conditions associated with an increasingly aged population. The strategy entails ex vivo expansion of multipotential populations followed by delivery to the site of damage on dynamically durable-biodegradable three-dimensional structures which provide the requisite extracellular microenvironment for stem cell driven tissue development. This review will examine bone stem cell biology, and current advances in skeletal tissue engineering through the enhancement and marrying of biologically informed and clinically relevant strategies.
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Affiliation(s)
- Jonathan I Dawson
- Bone and Joint Research Group, Centre for Human Development, Stem Cells and Regeneration, Developmental Origins of Health and Disease, Institute of Developmental Sciences, University of Southampton, Southampton SO16 6YD, UK.
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