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Tresoldi C, Bianchi E, Pellegata AF, Dubini G, Mantero S. Estimation of the physiological mechanical conditioning in vascular tissue engineering by a predictive fluid-structure interaction approach. Comput Methods Biomech Biomed Engin 2017; 20:1077-1088. [DOI: 10.1080/10255842.2017.1332192] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/19/2022]
Affiliation(s)
- Claudia Tresoldi
- Department of Chemistry, Materials, and Chemical Engineering ‘Giulio Natta’, Politecnico di Milano, Milan, Italy
| | - Elena Bianchi
- Department of Chemistry, Materials, and Chemical Engineering ‘Giulio Natta’, Politecnico di Milano, Milan, Italy
| | - Alessandro Filippo Pellegata
- Department of Chemistry, Materials, and Chemical Engineering ‘Giulio Natta’, Politecnico di Milano, Milan, Italy
| | - Gabriele Dubini
- Department of Chemistry, Materials, and Chemical Engineering ‘Giulio Natta’, Politecnico di Milano, Milan, Italy
| | - Sara Mantero
- Department of Chemistry, Materials, and Chemical Engineering ‘Giulio Natta’, Politecnico di Milano, Milan, Italy
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52
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Tubular collagen scaffolds with radial elasticity for hollow organ regeneration. Acta Biomater 2017; 52:1-8. [PMID: 28179160 DOI: 10.1016/j.actbio.2017.02.005] [Citation(s) in RCA: 27] [Impact Index Per Article: 3.9] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/31/2016] [Revised: 01/24/2017] [Accepted: 02/02/2017] [Indexed: 01/05/2023]
Abstract
Tubular collagen scaffolds have been used for the repair of damaged hollow organs in regenerative medicine, but they generally lack the ability to reversibly expand in radial direction, a physiological characteristic seen in many native tubular organs. In this study, tubular collagen scaffolds were prepared that display a shape recovery effect and therefore exhibit radial elasticity. Scaffolds were constructed by compression of fibrillar collagen around a star-shaped mandrel, mimicking folds in a lumen, a typical characteristic of empty tubular hollow organs, such as ureter or urethra. Shape recovery effect was introduced by in situ fixation using a star-shaped mandrel, 3D-printed clamps and cytocompatible carbodiimide crosslinking. Prepared scaffolds expanded upon increase of luminal pressure and closed to the star-shaped conformation after removal of pressure. In this study, we applied this method to construct a scaffold mimicking the dynamics of human urethra. Radial expansion and closure of the scaffold could be iteratively performed for at least 1000 cycles, burst pressure being 132±22mmHg. Scaffolds were seeded with human epithelial cells and cultured in a bioreactor under dynamic conditions mimicking urination (pulse flow of 21s every 2h). Cells adhered and formed a closed luminal layer that resisted flow conditions. In conclusion, a new type of a tubular collagen scaffold has been constructed with radial elastic-like characteristics based on the shape of the scaffold, and enabling the scaffold to reversibly expand upon increase in luminal pressure. These scaffolds may be useful for regenerative medicine of tubular organs. STATEMENT OF SIGNIFICANCE In this paper, a new type I collagen-based tubular scaffold is presented that possesses intrinsic radial elasticity. This characteristic is key to the functioning of a number of tubular organs including blood vessels and organs of the gastrointestinal and urogenital tract. The scaffold was given a star-shaped lumen by physical compression and chemical crosslinking, mimicking the folding pattern observed in many tubular organs. In rest, the lumen is closed but it opens upon increase of luminal pressure, e.g. when fluids pass. Human epithelial cells seeded on the luminal side adhered well and were compatible with voiding dynamics in a bioreactor. Collagen scaffolds with radial elasticity may be useful in the regeneration of dynamic tubular organs.
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53
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Loneker AE, Luketich SK, Bernstein D, Kalra A, Nugent AW, D'Amore A, Faulk DM. Mechanical and microstructural analysis of a radially expandable vascular conduit for neonatal and pediatric cardiovascular surgery. J Biomed Mater Res B Appl Biomater 2017; 106:659-671. [PMID: 28296198 DOI: 10.1002/jbm.b.33874] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/18/2016] [Revised: 01/20/2017] [Accepted: 02/20/2017] [Indexed: 01/29/2023]
Abstract
In pediatric cardiovascular surgery, there is a significant need for vascular prostheses that have the potential to grow with the patient following implantation. Current clinical options consist of nonexpanding conduits, requiring repeat surgeries as the patient outgrows the device. To address this issue, PECA Labs has developed a novel ePTFE vascular conduit with the capability of being radially expanded via balloon catheterization. In the described study, a systematic characterization and comparison of two proprietary ePTFE expandable conduits was conducted. Conduit sizes of 8 and 16 mm inner diameters for both conduits were evaluated before and after expansion with a 26 mm balloon. Comprehensive mechanical testing was completed, including quantification of circumferential, and longitudinal tensile strength, suture retention strength, burst strength, water entry pressure, dynamic compliance, and kink radius. Scanning electron microscopy was used to investigate the microstructural properties. Automated extraction of the fiber architectural features for each scanning electron micrograph was achieved with an algorithm for each conduit before and after expansion. Results showed that both conduits were able to expand significantly, to as much as 2.5× their original inner diameter. All mechanical properties were within clinically acceptable values following expansion. Analysis of the microstructure properties of the conduits revealed that the circumferential main angle of orientation, orientation index, and spatial periodicity did not significantly change following expansion, whereas the node area fraction decreased post expansion. Successful proof-of-concept of this novel product represents a critical step toward clinical translation and provides hope for newborns and growing children with congenital heart disease. © 2017 Wiley Periodicals, Inc. J Biomed Mater Res Part B: Appl Biomater, 106B: 659-671, 2018.
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Affiliation(s)
- Abigail E Loneker
- Department of Bioengineering, University of Pittsburgh, Pittsburgh, Penninsylvania
| | - Samuel K Luketich
- Department of Bioengineering, University of Pittsburgh, Pittsburgh, Penninsylvania.,McGowan Institute for Regenerative Medicine, University of Pittsburgh, Pittsburgh, Penninsylvania
| | | | - Arush Kalra
- PECA Labs, Pittsburgh, Penninsylvania, 15224
| | - Alan W Nugent
- University of Texas Southwestern Medical Center, Dallas, Texas
| | - Antonio D'Amore
- Department of Bioengineering, University of Pittsburgh, Pittsburgh, Penninsylvania.,McGowan Institute for Regenerative Medicine, University of Pittsburgh, Pittsburgh, Penninsylvania.,Department of Surgery, University of Pittsburgh, Pittsburgh, Penninsylvania.,School of Medicine, University of Pittsburgh, Pittsburgh, Penninsylvania.,RiMED Foundation, Palermo, Italy
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Lavery KS, Rhodes C, Mcgraw A, Eppihimer MJ. Anti-thrombotic technologies for medical devices. Adv Drug Deliv Rev 2017; 112:2-11. [PMID: 27496703 DOI: 10.1016/j.addr.2016.07.008] [Citation(s) in RCA: 53] [Impact Index Per Article: 7.6] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/19/2016] [Revised: 06/03/2016] [Accepted: 07/26/2016] [Indexed: 01/08/2023]
Abstract
Thrombosis associated with medical devices may lead to dramatic increases in morbidity, mortality and increased health care costs. Innovative strategies are being developed to reduce this complication and provide a safe biocompatible interface between device and blood. This article aims to describe the biological phenomena underlying device-associated thrombosis, and surveys the literature describing current and developing technologies designed to overcome this challenge. To reduce thrombosis, biomaterials with varying topographical properties and incorporating anti-thrombogenic substances on their surface have demonstrated potential. Overall, there is extensive literature describing technical solutions to reduce thrombosis associated with medical devices, but clinical results are required to demonstrate significant long-term benefits.
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Affiliation(s)
- Karen S Lavery
- Preclinical Sciences, Boston Scientific Corporation, 100 Boston Scientific Way, Marlborough, MA 01752-1234, United States
| | - Candace Rhodes
- Preclinical Sciences, Boston Scientific Corporation, 100 Boston Scientific Way, Marlborough, MA 01752-1234, United States
| | - Adam Mcgraw
- Preclinical Sciences, Boston Scientific Corporation, 100 Boston Scientific Way, Marlborough, MA 01752-1234, United States
| | - Michael J Eppihimer
- Preclinical Sciences, Boston Scientific Corporation, 100 Boston Scientific Way, Marlborough, MA 01752-1234, United States
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56
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Row S, Santandreu A, Swartz DD, Andreadis ST. Cell-free vascular grafts: Recent developments and clinical potential. TECHNOLOGY 2017; 5:13-20. [PMID: 28674697 PMCID: PMC5492388 DOI: 10.1142/s2339547817400015] [Citation(s) in RCA: 14] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/11/2023]
Abstract
Recent advances in vascular tissue engineering have led to the development of cell-free grafts that are available off-the-shelf for on demand surgery. Challenges associated with cell-based technologies including cell sourcing, cell expansion and long-term bioreactor culture motivated the development of completely cell-free vascular grafts. These are based on decellularized arteries, decellularized cultured cell-based tissue engineered grafts or biomaterials functionalized with biological signals that promote in situ tissue regeneration. Clinical trials undertaken to demonstrate the applicability of these grafts are also discussed. This comprehensive review summarizes recent developments in vascular graft technologies, with potential applications in coronary artery bypass procedures, lower extremity bypass, vascular injury and trauma, congenital heart diseases and dialysis access shunts, to name a few.
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Affiliation(s)
- Sindhu Row
- Department of Chemical and Biological Engineering, University at Buffalo, The State University of New York, Amherst, NY 14260-4200, USA
- Angiograft LLC, Amherst NY
| | - Ana Santandreu
- Department of Chemical and Biological Engineering, University at Buffalo, The State University of New York, Amherst, NY 14260-4200, USA
| | | | - Stelios T Andreadis
- Department of Chemical and Biological Engineering, University at Buffalo, The State University of New York, Amherst, NY 14260-4200, USA
- Department of Biomedical Engineering, University at Buffalo, The State University of New York, Amherst, NY 14260-4200, USA
- New York State Center of Excellence in Bioinformatics and Life Sciences, Buffalo, NY
- Angiograft LLC, Amherst NY
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57
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Dolan EB, Gunning GM, Davis TA, Cooney G, Eufrasio T, Murphy BP. The development and mechanical characterisation of a novel reinforced venous conduit that mimics the mechanical properties of an arterial wall. J Mech Behav Biomed Mater 2017; 71:23-31. [PMID: 28259025 DOI: 10.1016/j.jmbbm.2017.02.012] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/19/2016] [Revised: 02/03/2017] [Accepted: 02/08/2017] [Indexed: 12/24/2022]
Abstract
Venous grafts have been used to bypass stenotic arteries for many decades. However, this "gold standard" treatment is far from optimal, with long-term vein graft patency rates reported to be as low as 50% at >15 years. These results could be a result of the structural and functional differences of veins compared to arteries. In this study we developed a new protocol for manufacturing reinforced fresh veins with a decellularized porcine arterial scaffold. This novel method was designed to be replicated easily in a surgical setting, and manufactured reinforced constructs were robust and easier to handle than the veins alone. Furthermore, we demonstrate that these Reinforced Venous-Arterial Conduits have comparable mechanical properties to native arteries, in terms of ultimate tensile strength (UTS) (2.36 vs. 2.24MPa) and collagen dominant phase (11.04 vs. 12.26MPa). Therefore, the Reinforced Venous-Arterial Conduit combines the benefits of using the current gold standard homogenous venous grafts composed of a confluent endothelial surface, with an "off-the-shelf" decellularized artery to improve the mechanical properties to closely mimic those of native arteries, while maintaining the self-repairing characteristics of native tissue. In conclusion in this study we have produced a construct and a new technique that combines the mechanical properties of both a natural vein and a decellularized artery to produce a reinforced venous graft that closely mimics the mechanical response of an arterial segment.
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Affiliation(s)
- Eimear B Dolan
- Trinity Centre for Bioengineering, Trinity Biomedical Sciences Institute, 152-160 Pearse Street, Trinity College Dublin, Dublin 2, Ireland; Department of Mechanical and Manufacturing Engineering, School of Engineering, Trinity College Dublin, Dublin 2, Ireland; Department of Anatomy, Royal College of Surgeons in Ireland, Dublin, Ireland
| | - Gillian M Gunning
- Trinity Centre for Bioengineering, Trinity Biomedical Sciences Institute, 152-160 Pearse Street, Trinity College Dublin, Dublin 2, Ireland; Department of Mechanical and Manufacturing Engineering, School of Engineering, Trinity College Dublin, Dublin 2, Ireland
| | - Travis A Davis
- Trinity Centre for Bioengineering, Trinity Biomedical Sciences Institute, 152-160 Pearse Street, Trinity College Dublin, Dublin 2, Ireland; Department of Mechanical and Manufacturing Engineering, School of Engineering, Trinity College Dublin, Dublin 2, Ireland
| | - Gerard Cooney
- Trinity Centre for Bioengineering, Trinity Biomedical Sciences Institute, 152-160 Pearse Street, Trinity College Dublin, Dublin 2, Ireland; Department of Mechanical and Manufacturing Engineering, School of Engineering, Trinity College Dublin, Dublin 2, Ireland
| | - Tatiane Eufrasio
- Trinity Centre for Bioengineering, Trinity Biomedical Sciences Institute, 152-160 Pearse Street, Trinity College Dublin, Dublin 2, Ireland; Advanced Materials and Bioengineering Research Centre (AMBER), Trinity College Dublin, Dublin 2, Ireland; Department of Anatomy, Royal College of Surgeons in Ireland, Dublin, Ireland
| | - Bruce P Murphy
- Trinity Centre for Bioengineering, Trinity Biomedical Sciences Institute, 152-160 Pearse Street, Trinity College Dublin, Dublin 2, Ireland; Department of Mechanical and Manufacturing Engineering, School of Engineering, Trinity College Dublin, Dublin 2, Ireland; Advanced Materials and Bioengineering Research Centre (AMBER), Trinity College Dublin, Dublin 2, Ireland.
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58
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A Dual-Mode Bioreactor System for Tissue Engineered Vascular Models. Ann Biomed Eng 2017; 45:1496-1510. [DOI: 10.1007/s10439-017-1813-9] [Citation(s) in RCA: 15] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/29/2016] [Accepted: 02/11/2017] [Indexed: 12/13/2022]
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59
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Cui H, Nowicki M, Fisher JP, Zhang LG. 3D Bioprinting for Organ Regeneration. Adv Healthc Mater 2017; 6:10.1002/adhm.201601118. [PMID: 27995751 PMCID: PMC5313259 DOI: 10.1002/adhm.201601118] [Citation(s) in RCA: 271] [Impact Index Per Article: 38.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/30/2016] [Revised: 10/26/2016] [Indexed: 12/19/2022]
Abstract
Regenerative medicine holds the promise of engineering functional tissues or organs to heal or replace abnormal and necrotic tissues/organs, offering hope for filling the gap between organ shortage and transplantation needs. Three-dimensional (3D) bioprinting is evolving into an unparalleled biomanufacturing technology due to its high-integration potential for patient-specific designs, precise and rapid manufacturing capabilities with high resolution, and unprecedented versatility. It enables precise control over multiple compositions, spatial distributions, and architectural accuracy/complexity, therefore achieving effective recapitulation of microstructure, architecture, mechanical properties, and biological functions of target tissues and organs. Here we provide an overview of recent advances in 3D bioprinting technology, as well as design concepts of bioinks suitable for the bioprinting process. We focus on the applications of this technology for engineering living organs, focusing more specifically on vasculature, neural networks, the heart and liver. We conclude with current challenges and the technical perspective for further development of 3D organ bioprinting.
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Affiliation(s)
- Haitao Cui
- Department of Mechanical and Aerospace Engineering, The George Washington University, 3590 Science and Engineering Hall, 800 22nd Street NW, Washington, DC 20052, USA
| | - Margaret Nowicki
- Department of Biomedical Engineering, The George Washington University, 3590 Science and Engineering Hall, 800 22nd Street NW, Washington, DC 20052, USA
| | - John P. Fisher
- Department of Bioengineering University of Maryland 3238 Jeong H. Kim Engineering Building College Park, MD 20742, USA
| | - Lijie Grace Zhang
- Department of Medicine, The George Washington University, 3590 Science and Engineering Hall, 800 22nd Street NW, Washington, DC 20052, USA
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60
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Maschhoff P, Heene S, Lavrentieva A, Hentrop T, Leibold C, Wahalla MN, Stanislawski N, Blume H, Scheper T, Blume C. An intelligent bioreactor system for the cultivation of a bioartificial vascular graft. Eng Life Sci 2016; 17:567-578. [PMID: 32624802 DOI: 10.1002/elsc.201600138] [Citation(s) in RCA: 12] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/20/2016] [Revised: 11/18/2016] [Accepted: 11/28/2016] [Indexed: 11/09/2022] Open
Abstract
Cardiovascular disease is the most common cause of death, accounting for 31% of deaths worldwide. As purely synthetic grafts implicate concomitant anticoagulation and autologous veins are rare, tissue-engineered vascular grafts are urgently needed. For successful in vitro cultivation of a bioartificial vascular graft, the suitable bioreactor should provide conditions comparable to vasculogenesis in the body. Such a system has been developed and characterized under continuous and pulsatile flow, and a variety of sensors has been integrated into the bioreactor to control parameters such as temperature, pressure up to 500 mbar, glucose up to 4.5 g/L, lactate, oxygen up to 150 mbar, and flow rate. Wireless data transfer (using the ZigBee specification based on the IEEE 802.15.4 standard) and multiple corresponding sensor signal processing platforms have been implemented as well. Ultrasound is used for touchless monitoring of the growing vascular structure as a quality control before implantation (maximally achieved ultrasound resolution 65 μm at 15 MHz). To withstand the harsh conditions of steam sterilization (120°C for 20 min), all electronics were encapsulated. With such a comprehensive physiologically conditioning, sensing, and imaging bioreactor system, all the requirements for a successful cultivation of vascular grafts are available now.
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Affiliation(s)
- Paul Maschhoff
- Institute of Technical Chemistry Leibniz University Hannover Germany
| | - Sebastian Heene
- Institute of Technical Chemistry Leibniz University Hannover Germany
| | | | - Thorleif Hentrop
- Institute of Technical Chemistry Leibniz University Hannover Germany
| | - Christian Leibold
- Institute for Microelectronic Systems Leibniz University Hannover Germany
| | - Marc-Nils Wahalla
- Institute for Microelectronic Systems Leibniz University Hannover Germany
| | - Nils Stanislawski
- Institute of Technical Chemistry Leibniz University Hannover Germany.,Institute for Microelectronic Systems Leibniz University Hannover Germany
| | - Holger Blume
- Institute for Microelectronic Systems Leibniz University Hannover Germany
| | - Thomas Scheper
- Institute of Technical Chemistry Leibniz University Hannover Germany
| | - Cornelia Blume
- Institute of Technical Chemistry Leibniz University Hannover Germany
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61
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Dahan N, Sarig U, Bronshtein T, Baruch L, Karram T, Hoffman A, Machluf M. Dynamic Autologous Reendothelialization of Small-Caliber Arterial Extracellular Matrix: A Preclinical Large Animal Study. Tissue Eng Part A 2016; 23:69-79. [PMID: 27784199 PMCID: PMC5240014 DOI: 10.1089/ten.tea.2016.0126] [Citation(s) in RCA: 40] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [Abstract] [Key Words] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/26/2022] Open
Abstract
Effective cellularization is a key approach to prevent small-caliber (<4 mm) tissue-engineered vascular graft (TEVG) failure and maintain patency and contractility following implantation. To achieve this goal, however, improved biomimicking designs and/or relatively long production times (typically several months) are required. We previously reported on porcine carotid artery decellularization yielding biomechanically stable and cell supportive small-caliber (3–4 mm diameter, 5 cm long) arterial extracellular matrix (scaECM) vascular grafts. In this study, we aimed to study the scaECM graft patency in vivo and possibly improve that patency by graft pre-endothelialization with the recipient porcine autologous cells using our previously reported custom-designed dynamic perfusion bioreactor system. Decellularized scaECM vascular grafts were histologically characterized, their immunoreactivity studied in vitro, and their biocompatibility profile evaluated as a xenograft subcutaneous implantation in a mouse model. To study the scaECM cell support and remodeling ability, pig autologous endothelial and smooth muscle cells (SMCs) were seeded and dynamically cultivated within the scaECM lumen and externa/media, respectively. Finally, endothelialized-only scaECMs—hypothesized as a prerequisite for maintaining graft patency and controlling intimal hyperplasia—were transplanted as an interposition carotid artery graft in a porcine model. Graft patency was evaluated through angiography online and endpoint pathological assessment for up to 6 weeks. Our results demonstrate the scaECM-TEVG biocompatibility preserving a structurally and mechanically stable vascular wall not just following decellularization and recellularization but also after implantation. Using our dynamic perfusion bioreactor, we successfully demonstrated the ability of this TEVG to support in vitro recellularization and remodeling by primary autologous endothelial and SMCs, which were seeded on the lumen and the externa/media layers, respectively. Following transplantation, dynamically endothelialized scaECM-TEVGs remained patent for 6 weeks in a pig carotid interposition bypass model. When compared with nonrevitalized control grafts, reendothelialized grafts provided excellent antithrombogenic activity, inhibited intimal hyperplasia formation, and encouraged media wall infiltration and reorganization with recruited host SMCs. We thus demonstrate that readily available decellularized scaECM can be promptly revitalized with autologous cells in a 3-week period before implantation, indicating applicability as a future platform for vascular reconstructive procedures.
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Affiliation(s)
- Nitsan Dahan
- 1 Faculty of Biotechnology and Food Engineering, Technion-Israel Institute of Technology , Haifa, Israel
| | - Udi Sarig
- 1 Faculty of Biotechnology and Food Engineering, Technion-Israel Institute of Technology , Haifa, Israel .,2 School of Materials Science and Engineering, Nanyang Technological University (NTU) , Singapore, Singapore
| | - Tomer Bronshtein
- 1 Faculty of Biotechnology and Food Engineering, Technion-Israel Institute of Technology , Haifa, Israel
| | - Limor Baruch
- 1 Faculty of Biotechnology and Food Engineering, Technion-Israel Institute of Technology , Haifa, Israel
| | - Tony Karram
- 3 Department of Vascular Surgery and Transplantation, Rambam Health Care Campus, Technion-Israel Institute of Technology , Haifa, Israel
| | - Aaron Hoffman
- 3 Department of Vascular Surgery and Transplantation, Rambam Health Care Campus, Technion-Israel Institute of Technology , Haifa, Israel
| | - Marcelle Machluf
- 1 Faculty of Biotechnology and Food Engineering, Technion-Israel Institute of Technology , Haifa, Israel .,2 School of Materials Science and Engineering, Nanyang Technological University (NTU) , Singapore, Singapore
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62
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Longitudinal Stretching for Maturation of Vascular Tissues Using Magnetic Forces. Bioengineering (Basel) 2016; 3:bioengineering3040029. [PMID: 28952591 PMCID: PMC5597272 DOI: 10.3390/bioengineering3040029] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/23/2016] [Revised: 09/26/2016] [Accepted: 10/31/2016] [Indexed: 12/03/2022] Open
Abstract
Cellular spheroids were studied to determine their use as “bioinks” in the biofabrication of tissue engineered constructs. Specifically, magnetic forces were used to mediate the cyclic longitudinal stretching of tissues composed of Janus magnetic cellular spheroids (JMCSs), as part of a post-processing method for enhancing the deposition and mechanical properties of an extracellular matrix (ECM). The purpose was to accelerate the conventional tissue maturation process via novel post-processing techniques that accelerate the functional, structural, and mechanical mimicking of native tissues. The results of a forty-day study of JMCSs indicated an expression of collagen I, collagen IV, elastin, and fibronectin, which are important vascular ECM proteins. Most notably, the subsequent exposure of fused tissue sheets composed of JMCSs to magnetic forces did not hinder the production of these key proteins. Quantitative results demonstrate that cyclic longitudinal stretching of the tissue sheets mediated by these magnetic forces increased the Young’s modulus and induced collagen fiber alignment over a seven day period, when compared to statically conditioned controls. Specifically, the elastin and collagen content of these dynamically-conditioned sheets were 35- and three-fold greater, respectively, at seven days compared to the statically-conditioned controls at three days. These findings indicate the potential of using magnetic forces in tissue maturation, specifically through the cyclic longitudinal stretching of tissues.
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63
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Hiob MA, She S, Muiznieks LD, Weiss AS. Biomaterials and Modifications in the Development of Small-Diameter Vascular Grafts. ACS Biomater Sci Eng 2016; 3:712-723. [DOI: 10.1021/acsbiomaterials.6b00220] [Citation(s) in RCA: 51] [Impact Index Per Article: 6.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Affiliation(s)
- Matti A. Hiob
- School of Life and Environmental Sciences, University of Sydney, Sydney, NSW 2006, Australia
- Charles Perkins Centre, University of Sydney, Sydney, NSW 2006, Australia
| | - Shelley She
- School of Life and Environmental Sciences, University of Sydney, Sydney, NSW 2006, Australia
- Charles Perkins Centre, University of Sydney, Sydney, NSW 2006, Australia
| | - Lisa D. Muiznieks
- Molecular Structure and Function Program, Research Institute, Hospital for Sick Children, 555 University Avenue, Toronto, ON M5G1X8, Canada
| | - Anthony S. Weiss
- School of Life and Environmental Sciences, University of Sydney, Sydney, NSW 2006, Australia
- Charles Perkins Centre, University of Sydney, Sydney, NSW 2006, Australia
- Bosch Institute, University of Sydney, Sydney, NSW 2006, Australia
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64
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Li ZK, Wu ZS, Lu T, Yuan HY, Tang H, Tang ZJ, Tan L, Wang B, Yan SM. Materials and surface modification for tissue engineered vascular scaffolds. JOURNAL OF BIOMATERIALS SCIENCE-POLYMER EDITION 2016; 27:1534-52. [PMID: 27484610 DOI: 10.1080/09205063.2016.1217607] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 12/13/2022]
Abstract
Although vascular implantation has been used as an effective treatment for cardiovascular disease for many years, off-the-shelf and regenerable vascular scaffolds are still not available. Tissue engineers have tested various materials and methods of surface modification in the attempt to develop a scaffold that is more suitable for implantation. Extracellular matrix-based natural materials and biodegradable polymers, which are the focus of this review, are considered to be suitable materials for production of tissue-engineered vascular grafts. Various methods of surface modification that have been developed will also be introduced, their impacts will be summarized and assessed, and challenges for further research will briefly be discussed.
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Affiliation(s)
- Zhong-Kui Li
- a Department of Cardiovascular Surgery , Second Xiangya Hospital of Central South University , Changsha , PR China
| | - Zhong-Shi Wu
- a Department of Cardiovascular Surgery , Second Xiangya Hospital of Central South University , Changsha , PR China
| | - Ting Lu
- a Department of Cardiovascular Surgery , Second Xiangya Hospital of Central South University , Changsha , PR China
| | - Hao-Yong Yuan
- a Department of Cardiovascular Surgery , Second Xiangya Hospital of Central South University , Changsha , PR China
| | - Hao Tang
- a Department of Cardiovascular Surgery , Second Xiangya Hospital of Central South University , Changsha , PR China
| | - Zhen-Jie Tang
- a Department of Cardiovascular Surgery , Second Xiangya Hospital of Central South University , Changsha , PR China
| | - Ling Tan
- a Department of Cardiovascular Surgery , Second Xiangya Hospital of Central South University , Changsha , PR China
| | - Bin Wang
- a Department of Cardiovascular Surgery , Second Xiangya Hospital of Central South University , Changsha , PR China
| | - Si-Ming Yan
- a Department of Cardiovascular Surgery , Second Xiangya Hospital of Central South University , Changsha , PR China
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65
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Wengerter BC, Emre G, Park JY, Geibel J. Three-dimensional Printing in the Intestine. Clin Gastroenterol Hepatol 2016; 14:1081-5. [PMID: 27189913 DOI: 10.1016/j.cgh.2016.05.008] [Citation(s) in RCA: 23] [Impact Index Per Article: 2.9] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 08/20/2015] [Revised: 05/02/2016] [Accepted: 05/04/2016] [Indexed: 02/07/2023]
Abstract
Intestinal transplantation remains a life-saving option for patients with severe intestinal failure. With the advent of advanced tissue engineering techniques, great strides have been made toward manufacturing replacement tissues and organs, including the intestine, which aim to avoid transplant-related complications. The current paradigm is to seed a biocompatible support material (scaffold) with a desired cell population to generate viable replacement tissue. Although this technique has now been extended by the three-dimensional (3D) printing of geometrically complex scaffolds, the overall approach is hindered by relatively slow turnover and negative effects of residual scaffold material, which affects final clinical outcome. Methods recently developed for scaffold-free 3D bioprinting may overcome such obstacles and should allow for rapid manufacture and deployment of "bioprinted organs." Much work remains before 3D bioprinted tissues can enter clinical use. In this brief review we examine the present state and future perspectives of this nascent technology before full clinical implementation.
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Affiliation(s)
- Brian C Wengerter
- Department of Surgery, Yale University School of Medicine, New Haven, Connecticut
| | - Gulus Emre
- Department of Surgery, Yale University School of Medicine, New Haven, Connecticut
| | - Jea Young Park
- Department of Surgery, Yale University School of Medicine, New Haven, Connecticut
| | - John Geibel
- Department of Surgery, Yale University School of Medicine, New Haven, Connecticut.
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Stefani I, Cooper-White J. Development of an in-process UV-crosslinked, electrospun PCL/aPLA-co-TMC composite polymer for tubular tissue engineering applications. Acta Biomater 2016; 36:231-40. [PMID: 26969522 DOI: 10.1016/j.actbio.2016.03.013] [Citation(s) in RCA: 27] [Impact Index Per Article: 3.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/02/2015] [Revised: 02/29/2016] [Accepted: 03/07/2016] [Indexed: 01/14/2023]
Abstract
UNLABELLED Cardiovascular diseases remain the largest cause of death worldwide, and half of these deaths are the result of failure of the vascular system. Tissue engineering promises to provide new, and potentially more effective therapeutic strategies to replace damaged or degenerated vessels with functional vessels. However, these engineered vessels have substantial performance criteria, including vessel-like tubular shape, structure and mechanical property slate. Further, whether implanted without or with prior in vitro culture, such tubular scaffolds must provide a suitable environment for cell adhesion and growth and be of sufficient porosity to permit cell colonization. This study investigates the fabrication of slowly degradable, composite tubular polymer scaffolds made from polycaprolactone (PCL) and acrylated l-lactide-co-trimethylene carbonate (aPLA-co-TMC). The addition of acrylate groups permits the 'in-process' formation of crosslinks between aPLA-co-TMC chains during electrospinning of the composite system, exemplifying a novel process to produce multicomponent, elastomeric electrospun polymer scaffolds. Although PCL and aPLA-co-TMC were miscible in a co-solvent, a criteria for electrospinning, due to thermodynamic incompatibility of the two polymers as melts, solvent evaporation during electrospinning drove phase separation of these two systems, producing 'core-shell' fibres, with the core being composed of PCL, and the shell of crosslinked elastomeric aPLA-co-TMC. The resulting elastic fibrous scaffolds displayed burst pressures and suture retention strengths comparable with human arteries. Cytocompatibility testing with human mesenchymal stem cells confirmed adhesion to, and proliferation on the three-dimensional fibrous network, as well as alignment with highly-organized fibres. This new processing methodology and resulting mechanically-robust composite scaffolds hold significant promise for tubular tissue engineering applications. STATEMENT OF SIGNIFICANCE Autologous small diameter blood vessel grafts are unsuitable solutions for vessel repair. Engineered solutions such as tubular biomaterial scaffolds however have substantial performance criteria to meet, including vessel-like tubular shape, structure and mechanical property slate. We detail herein an innovative methodology to co-electrospin and 'in-process' crosslink composite mixtures of Poly(caprolactone) and a newly synthesised acrylated-Poly(lactide-co-trimethylene-carbonate) to create elastomeric, core-shell nanofibrous porous scaffolds in a one-step process. This novel composite system can be used to make aligned scaffolds that encourage stem cell adhesion, growth and morphological control, and produce robust tubular scaffolds of tunable internal diameter and wall thickness that possess mechanical properties approaching those of native vessels, ideal for future applications in the field of vessel tissue engineering.
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Zheng L, Chen L, Chen Y, Gui J, Li Q, Huang Y, Liu M, Jia X, Song W, Ji J, Gong X, Shi R, Fan Y. The effects of fluid shear stress on proliferation and osteogenesis of human periodontal ligament cells. J Biomech 2016; 49:572-9. [PMID: 26892895 DOI: 10.1016/j.jbiomech.2016.01.034] [Citation(s) in RCA: 22] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/23/2015] [Revised: 01/08/2016] [Accepted: 01/28/2016] [Indexed: 01/26/2023]
Abstract
Shear stress is one of the main stress type produced by speech, mastication or tooth movement. The mechano-response of human periodontal ligament (PDL) cells by shear stress and the mechanism are largely unknown. In our study, we investigated the effects of fluid shear stress on proliferation, migration and osteogenic potential of human PDL cells. 6dyn/cm(2) of fluid shear stress was produced in a parallel plate flow chamber. Our results demonstrated that fluid shear stress rearranged the orientation of human PDL cells. In addition, fluid shear stress inhibited human PDL cell proliferation and migration, but increased the osteogenic potential and expression of several growth factors and cytokines. Our study suggested that shear stress is involved in homeostasis regulation in human PDL cells. Inhibiting proliferation and migration potentially induce PDL cells to respond to mechanical stimuli in order to undergo osteogenic differentiation.
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Affiliation(s)
- Lisha Zheng
- Key Laboratory for Biomechanics and Mechanobiology of Ministry of Education, School of Biological Science and Medical Engineering, Beihang University, Beijing 100191, China
| | - Luoping Chen
- Key Laboratory for Biomechanics and Mechanobiology of Ministry of Education, School of Biological Science and Medical Engineering, Beihang University, Beijing 100191, China
| | - Yuchao Chen
- Key Laboratory for Biomechanics and Mechanobiology of Ministry of Education, School of Biological Science and Medical Engineering, Beihang University, Beijing 100191, China
| | - Jinpeng Gui
- Key Laboratory for Biomechanics and Mechanobiology of Ministry of Education, School of Biological Science and Medical Engineering, Beihang University, Beijing 100191, China
| | - Qing Li
- Center of Digital Dentistry, Peking University School and Hospital of Stomatology, National Engineering Laboratory for Digital and Material Technology of Stomatology, 100081, China
| | - Yan Huang
- Key Laboratory for Biomechanics and Mechanobiology of Ministry of Education, School of Biological Science and Medical Engineering, Beihang University, Beijing 100191, China
| | - Meili Liu
- Key Laboratory for Biomechanics and Mechanobiology of Ministry of Education, School of Biological Science and Medical Engineering, Beihang University, Beijing 100191, China
| | - Xiaolin Jia
- Key Laboratory for Biomechanics and Mechanobiology of Ministry of Education, School of Biological Science and Medical Engineering, Beihang University, Beijing 100191, China
| | - Wei Song
- Key Laboratory for Biomechanics and Mechanobiology of Ministry of Education, School of Biological Science and Medical Engineering, Beihang University, Beijing 100191, China
| | - Jing Ji
- Key Laboratory for Biomechanics and Mechanobiology of Ministry of Education, School of Biological Science and Medical Engineering, Beihang University, Beijing 100191, China
| | - Xianghui Gong
- Key Laboratory for Biomechanics and Mechanobiology of Ministry of Education, School of Biological Science and Medical Engineering, Beihang University, Beijing 100191, China
| | - Ruoshi Shi
- University Health Network, Ontario Cancer Institute/Princess Margaret Cancer Centre, Toronto, Ontario, Canada
| | - Yubo Fan
- Key Laboratory for Biomechanics and Mechanobiology of Ministry of Education, School of Biological Science and Medical Engineering, Beihang University, Beijing 100191, China; National Research Center for Rehabilitation Technical Aids, Beijing 100176, China.
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68
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Aper T, Wilhelmi M, Gebhardt C, Hoeffler K, Benecke N, Hilfiker A, Haverich A. Novel method for the generation of tissue-engineered vascular grafts based on a highly compacted fibrin matrix. Acta Biomater 2016; 29:21-32. [PMID: 26472610 DOI: 10.1016/j.actbio.2015.10.012] [Citation(s) in RCA: 49] [Impact Index Per Article: 6.1] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/05/2015] [Revised: 10/04/2015] [Accepted: 10/09/2015] [Indexed: 12/11/2022]
Abstract
The generation of tissue-engineered blood vessel substitutes remains an ongoing challenge for cardiovascular tissue engineering. Full biocompatibility and immediate availability have emerged as central issues for clinical use. To address these issues, we developed a technique that allows the generation of highly stable tubular fibrin segments. The process is based on the compaction of fibrin in a custom-made high-speed rotation mold. In an automated process, fibrin is precipitated from plasma by means of the Vivostat® system. Following application to the rotating mold, the fibrin was compacted by centrifugal force and excess fluid was pressed out. This compaction results in increasing cross-links between the fibrin fibrils and a corresponding significant increase of biomechanical stability up to a burst strength of 230mm of mercury. The molding process allows for a simultaneous seeding procedure. In a first in vivo evaluation in a sheep model, segments of the carotid artery were replaced by tissue-engineered vascular grafts, generated immediately prior to implantation (n=6). Following subjection to the body's remodeling mechanisms, the segments showed a high structural similarity to a native artery after explantation at 6months. Thus, this technique may represent a powerful tool for the generation of biomechanically stable vascular grafts immediately prior to implantation. STATEMENT OF SIGNIFICANCE Fibrin has previously been shown to be suitable as a matrix for the seeding of different celltypes and for that reason was widely used as scaffold in different fields of tissue engineering. Nevertheless, fibrin's lack of stability has strongly limited its application. Our study describes a novel moulding technique for the generation of a highly compacted fibrin matrix. Using this approach, it was possible to optimize the engineering process of tubular fibrin segments to provide bioartificial vascular grafts within one hour with sufficient stability for immediate implantation in the arterial system. Thus, this technique may represent a powerful tool to get closer to the ultimate aim of an optimal bioartificial vascular graft.
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Affiliation(s)
- Thomas Aper
- Department of Vascular and Endovascular Surgery, Division for Cardiothoracic-, Transplantation and Vascular Surgery, Hannover Medical School, Hannover, Germany.
| | - Mathias Wilhelmi
- Department of Vascular and Endovascular Surgery, Division for Cardiothoracic-, Transplantation and Vascular Surgery, Hannover Medical School, Hannover, Germany
| | - Christin Gebhardt
- Department of Vascular and Endovascular Surgery, Division for Cardiothoracic-, Transplantation and Vascular Surgery, Hannover Medical School, Hannover, Germany
| | - Klaus Hoeffler
- Department of Vascular and Endovascular Surgery, Division for Cardiothoracic-, Transplantation and Vascular Surgery, Hannover Medical School, Hannover, Germany
| | - Nils Benecke
- Department of Vascular and Endovascular Surgery, Division for Cardiothoracic-, Transplantation and Vascular Surgery, Hannover Medical School, Hannover, Germany
| | - Andres Hilfiker
- Department of Vascular and Endovascular Surgery, Division for Cardiothoracic-, Transplantation and Vascular Surgery, Hannover Medical School, Hannover, Germany
| | - Axel Haverich
- Department of Vascular and Endovascular Surgery, Division for Cardiothoracic-, Transplantation and Vascular Surgery, Hannover Medical School, Hannover, Germany
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69
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Customizable engineered blood vessels using 3D printed inserts. Methods 2015; 99:20-7. [PMID: 26732049 DOI: 10.1016/j.ymeth.2015.12.015] [Citation(s) in RCA: 31] [Impact Index Per Article: 3.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/29/2015] [Revised: 12/15/2015] [Accepted: 12/24/2015] [Indexed: 11/21/2022] Open
Abstract
Current techniques for tissue engineering blood vessels are not customizable for vascular size variation and vessel wall thickness. These critical parameters vary widely between the different arteries in the human body, and the ability to engineer vessels of varying sizes could increase capabilities for disease modeling and treatment options. We present an innovative method for producing customizable, tissue engineered, self-organizing vascular constructs by replicating a major structural component of blood vessels - the smooth muscle layer, or tunica media. We utilize a unique system combining 3D printed plate inserts to control construct size and shape, and cell sheets supported by a temporary fibrin hydrogel to encourage cellular self-organization into a tubular form resembling a natural artery. To form the vascular construct, 3D printed inserts are adhered to tissue culture plates, fibrin hydrogel is deposited around the inserts, and human aortic smooth muscle cells are then seeded atop the fibrin hydrogel. The gel, aided by the innate contractile properties of the smooth muscle cells, aggregates towards the center post insert, creating a tissue ring of smooth muscle cells. These rings are then stacked into the final tubular construct. Our methodology is robust, easily repeatable and allows for customization of cellular composition, vessel wall thickness, and length of the vessel construct merely by varying the size of the 3D printed inserts. This platform has potential for facilitating more accurate modeling of vascular pathology, serving as a drug discovery tool, or for vessel repair in disease treatment.
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70
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Battiston KG, Labow RS, Simmons CA, Santerre JP. Immunomodulatory polymeric scaffold enhances extracellular matrix production in cell co-cultures under dynamic mechanical stimulation. Acta Biomater 2015; 24:74-86. [PMID: 26093069 DOI: 10.1016/j.actbio.2015.05.038] [Citation(s) in RCA: 33] [Impact Index Per Article: 3.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/30/2015] [Revised: 05/19/2015] [Accepted: 05/28/2015] [Indexed: 12/16/2022]
Abstract
Despite the importance of immune cells in regulating the wound healing process following injury, there are few examples of synthetic biomaterials that have the capacity to push the body's immune cells toward pro-regeneration phenotypes, and fewer still that are designed with the intention of achieving this immunomodulatory character. While monocytes and their derived macrophages have been recognized as important contributors to tissue remodeling in vivo, this is primarily believed to be due to their ability to regulate other cell types. The ability of monocytes and macrophages to generate tissue products themselves, however, is currently not well appreciated within the field of tissue regeneration. Furthermore, while monocytes/macrophages are found in remodeling tissue that is subjected to mechanical loading, the effect this biomechanical strain on monocytes/macrophages and their ability to regulate tissue-specific cellular activity has not been understood due to the complexity of the many factors involved in the in vivo setting, hence necessitating the use of controlled in vitro culture platforms to investigate this phenomenon. In this study, human monocytes were co-cultured with human coronary artery smooth muscle cells (VSMCs) on a tubular (3mm ID) degradable polyurethane scaffold, with a unique combination of non-ionic polar, hydrophobic and ionic chemistry (D-PHI). The goal was to determine if such a synthetic matrix could be used in a co-culture system along with dynamic biomechanical stimulus (10% circumferential strain, 1Hz) conditions in order to direct monocytes to enhance tissue generation, and to better comprehend the different ways in which monocytes/macrophages may contribute to new tissue production. Mechanical strain and monocyte co-culture had a complementary and non-mitigating effect on VSMC growth. Co-culture samples demonstrated increased deposition of sulphated glycosaminoglycans (GAGs) and elastin, as well as increases in the release of FGF-2, a growth factor that can stimulate VSMC growth, while dynamic culture supported increases in collagen I and III as well as increased mechanical properties (elastic modulus, tensile strength) vs. static controls. Macrophage polarization toward an M1 state was not promoted by the biomaterial or culture conditions tested. Monocytes/macrophages cultured on D-PHI were also shown to produce vascular extracellular matrix components, including collagen I, collagen III, elastin, and GAGs. This study highlights the use of synthetic biomaterials having immunomodulatory character in order to promote cell and tissue growth when used in tissue engineering strategies, and identifies ECM deposition by monocytes/macrophages as an unexpected source of this new tissue. STATEMENT OF SIGNIFICANCE The ability of biomaterials to regulate macrophage activation towards a wound healing phenotype has recently been shown to support positive tissue regeneration. However, the ability of immunomodulatory biomaterials to harness monocyte/macrophage activity to support tissue engineering strategies in vitro holds enormous potential that has yet to be investigated. This study used a monocyte co-culture on a degradable polyurethane (D-PHI) to regulate the response of VSMCs in combination with biomechanical strain in a vascular tissue engineering context. Results demonstrate that immunomodulatory biomaterials, such as D-PHI, that support a desirable macrophage activation state can be combined with biomechanical strain to augment vascular tissue production in vitro, in part due to the novel and unexpected contribution of monocytes/macrophages themselves producing vascular ECM proteins.
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Affiliation(s)
- K G Battiston
- Institute of Biomaterials and Biomedical Engineering, University of Toronto, Toronto, Ontario M5S 3G9, Canada
| | - R S Labow
- Department of Biochemistry, Microbiology and Immunology, University of Ottawa, Ottawa, Ontario K1H 8M5, Canada
| | - C A Simmons
- Institute of Biomaterials and Biomedical Engineering, University of Toronto, Toronto, Ontario M5S 3G9, Canada; Faculty of Dentistry, University of Toronto, Toronto, Ontario M5G 1G6, Canada; Department of Mechanical and Industrial Engineering, University of Toronto, Toronto, Ontario M5S 3G8, Canada
| | - J P Santerre
- Institute of Biomaterials and Biomedical Engineering, University of Toronto, Toronto, Ontario M5S 3G9, Canada; Faculty of Dentistry, University of Toronto, Toronto, Ontario M5G 1G6, Canada.
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71
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Vallières K, Laterreur V, Tondreau MY, Ruel J, Germain L, Fradette J, Auger FA. Human adipose-derived stromal cells for the production of completely autologous self-assembled tissue-engineered vascular substitutes. Acta Biomater 2015; 24:209-19. [PMID: 26086693 DOI: 10.1016/j.actbio.2015.06.011] [Citation(s) in RCA: 24] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/19/2014] [Revised: 04/16/2015] [Accepted: 06/09/2015] [Indexed: 12/13/2022]
Abstract
There is a clinical need for small-diameter vascular substitutes, notably for coronary and peripheral artery bypass procedures since these surgeries are limited by the availability of grafting material. This study reports the characterization of a novel autologous tissue-engineered vascular substitute (TEVS) produced in 10weeks exclusively from human adipose-derived stromal cells (ASC) self-assembly, and its comparison to an established model made from dermal fibroblasts (DF). Briefly, ASC and DF were cultured with ascorbate to form cell sheets subsequently rolled around a mandrel. These TEVS were further cultured as a maturation period before undergoing mechanical testing, histological analyses and endothelialization. No significant differences were measured in burst pressure, suture strength, failure load, elastic modulus and failure strain according to the cell type used to produce the TEVS. Indeed, ASC- and DF-TEVS both displayed burst pressures well above maximal physiological blood pressure. However, ASC-TEVS were 1.40-fold more compliant than DF-TEVS. The structural matrix, comprising collagens type I and III, fibronectin and elastin, was very similar in all TEVS although histological analysis showed a wavier and less dense collagen matrix in ASC-TEVS. This difference in collagen organization could explain their higher compliance. Finally, human umbilical vein endothelial cells (HUVEC) successfully formed a confluent endothelium on ASC and DF cell sheets, as well as inside ASC-TEVS. Our results demonstrated that ASC are an alternative cell source for the production of TEVS displaying good mechanical properties and appropriate endothelialization.
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Affiliation(s)
- Karine Vallières
- Centre de recherche en organogénèse expérimentale de l'Université Laval/LOEX, Division of Regenerative Medicine, CHU de Québec Research Centre - Université Laval, Québec, QC, Canada; Department of Surgery, Faculty of Medicine, Université Laval, Québec, QC, Canada
| | - Véronique Laterreur
- Centre de recherche en organogénèse expérimentale de l'Université Laval/LOEX, Division of Regenerative Medicine, CHU de Québec Research Centre - Université Laval, Québec, QC, Canada; Department of Mechanical Engineering, Faculty of Science and Engineering, Université Laval, Québec, QC, Canada
| | - Maxime Y Tondreau
- Centre de recherche en organogénèse expérimentale de l'Université Laval/LOEX, Division of Regenerative Medicine, CHU de Québec Research Centre - Université Laval, Québec, QC, Canada; Department of Surgery, Faculty of Medicine, Université Laval, Québec, QC, Canada
| | - Jean Ruel
- Centre de recherche en organogénèse expérimentale de l'Université Laval/LOEX, Division of Regenerative Medicine, CHU de Québec Research Centre - Université Laval, Québec, QC, Canada; Department of Mechanical Engineering, Faculty of Science and Engineering, Université Laval, Québec, QC, Canada
| | - Lucie Germain
- Centre de recherche en organogénèse expérimentale de l'Université Laval/LOEX, Division of Regenerative Medicine, CHU de Québec Research Centre - Université Laval, Québec, QC, Canada; Department of Surgery, Faculty of Medicine, Université Laval, Québec, QC, Canada
| | - Julie Fradette
- Centre de recherche en organogénèse expérimentale de l'Université Laval/LOEX, Division of Regenerative Medicine, CHU de Québec Research Centre - Université Laval, Québec, QC, Canada; Department of Surgery, Faculty of Medicine, Université Laval, Québec, QC, Canada
| | - François A Auger
- Centre de recherche en organogénèse expérimentale de l'Université Laval/LOEX, Division of Regenerative Medicine, CHU de Québec Research Centre - Université Laval, Québec, QC, Canada; Department of Surgery, Faculty of Medicine, Université Laval, Québec, QC, Canada.
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72
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Steucke KE, Tracy PV, Hald ES, Hall JL, Alford PW. Vascular smooth muscle cell functional contractility depends on extracellular mechanical properties. J Biomech 2015; 48:3044-51. [PMID: 26283412 DOI: 10.1016/j.jbiomech.2015.07.029] [Citation(s) in RCA: 44] [Impact Index Per Article: 4.9] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/18/2015] [Revised: 07/21/2015] [Accepted: 07/23/2015] [Indexed: 11/17/2022]
Abstract
Vascular smooth muscle cells' primary function is to maintain vascular homeostasis through active contraction and relaxation. In diseases such as hypertension and atherosclerosis, this function is inhibited concurrent to changes in the mechanical environment surrounding vascular smooth muscle cells. It is well established that cell function and extracellular mechanics are interconnected; variations in substrate modulus affect cell migration, proliferation, and differentiation. To date, it is unknown how the evolving extracellular mechanical environment of vascular smooth muscle cells affects their contractile function. Here, we have built upon previous vascular muscular thin film technology to develop a variable-modulus vascular muscular thin film that measures vascular tissue functional contractility on substrates with a range of pathological and physiological moduli. Using this modified vascular muscular thin film, we found that vascular smooth muscle cells generated greater stress on substrates with higher moduli compared to substrates with lower moduli. We then measured protein markers typically thought to indicate a contractile phenotype in vascular smooth muscle cells and found that phenotype is unaffected by substrate modulus. These data suggest that mechanical properties of vascular smooth muscle cells' extracellular environment directly influence their functional behavior and do so without inducing phenotype switching.
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Affiliation(s)
- Kerianne E Steucke
- Department of Biomedical Engineering, University of Minnesota - Twin Cities, Minneapolis, MN 55455, United States
| | - Paige V Tracy
- Department of Biomedical Engineering, University of Minnesota - Twin Cities, Minneapolis, MN 55455, United States
| | - Eric S Hald
- Department of Biomedical Engineering, University of Minnesota - Twin Cities, Minneapolis, MN 55455, United States
| | - Jennifer L Hall
- Division of Cardiology, Department of Medicine, University of Minnesota - Twin Cities, Minneapolis, MN 55455, United States
| | - Patrick W Alford
- Department of Biomedical Engineering, University of Minnesota - Twin Cities, Minneapolis, MN 55455, United States.
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73
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Tresoldi C, Pellegata AF, Mantero S. Cells and stimuli in small-caliber blood vessel tissue engineering. Regen Med 2015; 10:505-27. [DOI: 10.2217/rme.15.19] [Citation(s) in RCA: 25] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/29/2022] Open
Abstract
The absence of successful solutions in treatments of small-caliber vessel diseases led to the Vascular Tissue Engineering approach to develop functional nonimmunogenic tissue engineered blood vessels. In this context, the choice of cells to be seeded and the microenvironment conditioning are pivotal. Biochemical and biomechanical stimuli seem to activate physiological regulatory pathways that induce the production of molecules and proteins stimulating stem cell differentiation toward vascular lineage and reproducing natural cross-talks among vascular cells to improve the maturation of tissue engineered blood vessels. Thus, this review focuses on (1) available cell sources, and (2) biochemical and biomechanical stimuli, with the final aim to obtain the long-term stability of the endothelium and mechanical properties suitable for withstanding physiological load.
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Affiliation(s)
- Claudia Tresoldi
- Department of Chemistry, Materials & Chemical Engineering “Giulio Natta”, Politecnico di Milano, Piazza Leonardo da Vinci 32, 20133, Milan, Italy
| | - Alessandro Filippo Pellegata
- Department of Chemistry, Materials & Chemical Engineering “Giulio Natta”, Politecnico di Milano, Piazza Leonardo da Vinci 32, 20133, Milan, Italy
| | - Sara Mantero
- Department of Chemistry, Materials & Chemical Engineering “Giulio Natta”, Politecnico di Milano, Piazza Leonardo da Vinci 32, 20133, Milan, Italy
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74
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Katsimpoulas M, Morticelli L, Michalopoulos E, Gontika I, Stavropoulos-Giokas C, Kostakis A, Haverich A, Korossis S. Investigation of the Biomechanical Integrity of Decellularized Rat Abdominal Aorta. Transplant Proc 2015; 47:1228-33. [DOI: 10.1016/j.transproceed.2014.11.061] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/09/2014] [Accepted: 11/13/2014] [Indexed: 10/23/2022]
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75
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Böer U, Hurtado-Aguilar LG, Klingenberg M, Lau S, Jockenhoevel S, Haverich A, Wilhelmi M. Effect of Intensified Decellularization of Equine Carotid Arteries on Scaffold Biomechanics and Cytotoxicity. Ann Biomed Eng 2015; 43:2630-41. [PMID: 25921001 DOI: 10.1007/s10439-015-1328-1] [Citation(s) in RCA: 18] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/08/2015] [Accepted: 04/20/2015] [Indexed: 12/26/2022]
Abstract
Decellularized equine carotid arteries (dEAC) are suggested to represent an alternative for alloplastic vascular grafts in haemodialysis patients to achieve vascular access. Recently it was shown that intensified detergent treatment completely removed cellular components from dEAC and thereby significantly reduced matrix immunogenicity. However, detergents may also affect matrix composition and stability and render scaffolds cytotoxic. Therefore, intensively decellularized carotids (int-dEAC) were now evaluated for their biomechanical characteristics (suture retention strength, burst pressure and circumferential compliance at arterial and venous systolic and diastolic pressure), matrix components (collagen and glycosaminoglycan content) and indirect and direct cytotoxicity (WST-8 assay and endothelial cell seeding) and compared with native (n-EAC) and conventionally decellularized carotids (con-dEAC). Both decellularization protocols comparably reduced matrix compliance (venous pressure compliance: 32.2 and 27.4% of n-EAC; p < 0.01 and arterial pressure compliance: 26.8 and 23.7% of n-EAC, p < 0.01) but had no effect on suture retention strength and burst pressure. Matrix characterization revealed unchanged collagen contents but a 39.0% (con-dEAC) and 26.4% (int-dEAC, p < 0.01) reduction of glycosaminoglycans, respectively. Cytotoxicity was not observed in either dEAC matrix which was also displayed by an intact endothelial lining after seeding. Thus, even intensified decellularization generates matrix scaffolds highly suitable for vascular tissue engineering purposes, e.g., the generation of haemodialysis shunts.
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Affiliation(s)
- Ulrike Böer
- GMP-Model Laboratory for Tissue Engineering, Feodor-Lynen-Str. 31, 30625, Hannover, Germany.
- Division for Cardiac-, Thoracic-, Transplantation- and Vascular Surgery, Hannover Medical School, Carl-Neuberg-Str. 1, 30625, Hannover, Germany.
| | - Luis G Hurtado-Aguilar
- Department of Tissue Engineering and Textile Implants, AME - Institute of Applied Medical Engineering, Helmholtz Institute, Pauwelsstr. 20, 52074, Aachen, Germany
| | - Melanie Klingenberg
- GMP-Model Laboratory for Tissue Engineering, Feodor-Lynen-Str. 31, 30625, Hannover, Germany
- Division for Cardiac-, Thoracic-, Transplantation- and Vascular Surgery, Hannover Medical School, Carl-Neuberg-Str. 1, 30625, Hannover, Germany
| | - Skadi Lau
- GMP-Model Laboratory for Tissue Engineering, Feodor-Lynen-Str. 31, 30625, Hannover, Germany
- Division for Cardiac-, Thoracic-, Transplantation- and Vascular Surgery, Hannover Medical School, Carl-Neuberg-Str. 1, 30625, Hannover, Germany
| | - Stefan Jockenhoevel
- Department of Tissue Engineering and Textile Implants, AME - Institute of Applied Medical Engineering, Helmholtz Institute, Pauwelsstr. 20, 52074, Aachen, Germany
| | - Axel Haverich
- GMP-Model Laboratory for Tissue Engineering, Feodor-Lynen-Str. 31, 30625, Hannover, Germany
- Division for Cardiac-, Thoracic-, Transplantation- and Vascular Surgery, Hannover Medical School, Carl-Neuberg-Str. 1, 30625, Hannover, Germany
| | - Mathias Wilhelmi
- GMP-Model Laboratory for Tissue Engineering, Feodor-Lynen-Str. 31, 30625, Hannover, Germany
- Division for Cardiac-, Thoracic-, Transplantation- and Vascular Surgery, Hannover Medical School, Carl-Neuberg-Str. 1, 30625, Hannover, Germany
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76
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Gurjarpadhye AA, DeWitt MR, Xu Y, Wang G, Rylander MN, Rylander CG. Dynamic Assessment of the Endothelialization of Tissue-Engineered Blood Vessels Using an Optical Coherence Tomography Catheter-Based Fluorescence Imaging System. Tissue Eng Part C Methods 2015; 21:758-66. [PMID: 25539889 DOI: 10.1089/ten.tec.2014.0345] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/12/2022] Open
Abstract
BACKGROUND Lumen endothelialization of bioengineered vascular scaffolds is essential to maintain small-diameter graft patency and prevent thrombosis postimplantation. Unfortunately, nondestructive imaging methods to visualize this dynamic process are lacking, thus slowing development and clinical translation of these potential tissue-engineering approaches. To meet this need, a fluorescence imaging system utilizing a commercial optical coherence tomography (OCT) catheter was designed to visualize graft endothelialization. METHODS C7 DragonFly™ intravascular OCT catheter was used as a channel for delivery and collection of excitation and emission spectra. Poly-dl-lactide (PDLLA) electrospun scaffolds were seeded with endothelial cells (ECs). Seeded cells were exposed to Calcein AM before imaging, causing the living cells to emit green fluorescence in response to blue laser. By positioning the catheter tip precisely over a specimen using high-fidelity electromechanical components, small regions of the specimen were excited selectively. The resulting fluorescence intensities were mapped on a two-dimensional digital grid to generate spatial distribution of fluorophores at single-cell-level resolution. Fluorescence imaging of endothelialization on glass and PDLLA scaffolds was performed using the OCT catheter-based imaging system as well as with a commercial fluorescence microscope. Cell coverage area was calculated for both image sets for quantitative comparison of imaging techniques. Tubular PDLLA scaffolds were maintained in a bioreactor on seeding with ECs, and endothelialization was monitored over 5 days using the OCT catheter-based imaging system. RESULTS No significant difference was observed in images obtained using our imaging system to those acquired with the fluorescence microscope. Cell area coverage calculated using the images yielded similar values. Nondestructive imaging of endothelialization on tubular scaffolds showed cell proliferation with cell coverage area increasing from 15 ± 4% to 89 ± 6% over 5 days. CONCLUSION In this study, we showed the capability of an OCT catheter-based imaging system to obtain single-cell resolution and to quantify endothelialization in tubular electrospun scaffolds. We also compared the resulting images with traditional microscopy, showing high fidelity in image capability. This imaging system, used in conjunction with OCT, could potentially be a powerful tool for in vitro optimization of scaffold cellularization, ensuring long-term graft patency postimplantation.
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Affiliation(s)
- Abhijit Achyut Gurjarpadhye
- 1 School of Biomedical Engineering and Sciences, Virginia Polytechnic Institute and State University , Blacksburg, Virginia
| | - Matthew R DeWitt
- 1 School of Biomedical Engineering and Sciences, Virginia Polytechnic Institute and State University , Blacksburg, Virginia
| | - Yong Xu
- 2 Department of Electrical and Computer Engineering, Virginia Polytechnic Institute and State University , Blacksburg, Virginia
| | - Ge Wang
- 3 Biomedical Imaging Cluster, Rensselaer Polytechnic Institute , Troy, New York
| | | | - Christopher G Rylander
- 4 Department of Mechanical Engineering, The University of Texas at Austin , Austin, Texas
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Dan P, Velot É, Decot V, Menu P. The role of mechanical stimuli in the vascular differentiation of mesenchymal stem cells. J Cell Sci 2015; 128:2415-22. [DOI: 10.1242/jcs.167783] [Citation(s) in RCA: 58] [Impact Index Per Article: 6.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/14/2022] Open
Abstract
Mesenchymal stem cells (MSCs) are among the most promising and suitable stem cell types for vascular tissue engineering. Substantial effort has been made to differentiate MSCs towards vascular cell phenotypes, including endothelial cells and smooth muscle cells (SMCs). The microenvironment of vascular cells not only contains biochemical factors that influence differentiation, but also exerts hemodynamic forces, such as shear stress and cyclic strain. Recent evidence has shown that these forces can influence the differentiation of MSCs into endothelial cells or SMCs. In this Commentary, we present the main findings in the area with the aim of summarizing the mechanisms by which shear stress and cyclic strain induce MSC differentiation. We will also discuss the interactions between these mechanical cues and other components of the microenvironment, and highlight how these insights could be used to maintain differentiation.
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Affiliation(s)
- Pan Dan
- UMR 7365 CNRS Université de Lorraine, Ingenierie Moleculaire et Physiopathologie Articulaire, Department of Cell and Tissue Engineering, Vectorization, Imaging, Biopôle de l'Université de Lorraine, Avenue de la forêt de Haye, C.S. 50184, Vandœuvre-lès-Nancy Cedex F-54505, France
- Department of Thoracic and Cardiovascular surgery, Zhongnan hospital of Wuhan University, Wuhan, 430071, China
| | - Émilie Velot
- UMR 7365 CNRS Université de Lorraine, Ingenierie Moleculaire et Physiopathologie Articulaire, Department of Cell and Tissue Engineering, Vectorization, Imaging, Biopôle de l'Université de Lorraine, Avenue de la forêt de Haye, C.S. 50184, Vandœuvre-lès-Nancy Cedex F-54505, France
| | - Véronique Decot
- UMR 7365 CNRS Université de Lorraine, Ingenierie Moleculaire et Physiopathologie Articulaire, Department of Cell and Tissue Engineering, Vectorization, Imaging, Biopôle de l'Université de Lorraine, Avenue de la forêt de Haye, C.S. 50184, Vandœuvre-lès-Nancy Cedex F-54505, France
- CHU de Nancy, Unité de Thérapie Cellulaire et Tissus, allée du Morvan, Vandœuvre-lès-Nancy F-54500, France
| | - Patrick Menu
- UMR 7365 CNRS Université de Lorraine, Ingenierie Moleculaire et Physiopathologie Articulaire, Department of Cell and Tissue Engineering, Vectorization, Imaging, Biopôle de l'Université de Lorraine, Avenue de la forêt de Haye, C.S. 50184, Vandœuvre-lès-Nancy Cedex F-54505, France
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Fercana G, Bowser D, Portilla M, Langan EM, Carsten CG, Cull DL, Sierad LN, Simionescu DT. Platform technologies for decellularization, tunic-specific cell seeding, and in vitro conditioning of extended length, small diameter vascular grafts. Tissue Eng Part C Methods 2014; 20:1016-27. [PMID: 24749889 DOI: 10.1089/ten.tec.2014.0047] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/29/2022] Open
Abstract
The aim of this study was to generate extended length, small diameter vascular scaffolds that could serve as potential grafts for treatment of acute ischemia. Biological tissues are considered excellent scaffolds, which exhibit adequate biological, mechanical, and handling properties; however, they tend to degenerate, dilate, and calcify after implantation. We hypothesized that chemically stabilized acellular arteries would be ideal scaffolds for development of vascular grafts for peripheral surgery applications. Based on promising historical data from our laboratory and others, we chose to decellularize bovine mammary and femoral arteries and test them as scaffolds for vascular grafting. Decellularization of such long structures required development of a novel "bioprocessing" system and a sequence of detergents and enzymes that generated completely acellular, galactose-(α1,3)-galactose (α-Gal) xenoantigen-free scaffolds with preserved collagen, elastin, and basement membrane components. Acellular arteries exhibited excellent mechanical properties, including burst pressure, suture holding strength, and elastic recoil. To reduce elastin degeneration, we treated the scaffolds with penta-galloyl glucose and then revitalized them in vitro using a tunic-specific cell approach. A novel atraumatic endothelialization protocol using an external stent was also developed for the long grafts and cell-seeded constructs were conditioned in a flow bioreactor. Both decellularization and revitalization are feasible but cell retention in vitro continues to pose challenges. These studies support further efforts toward clinical use of small diameter acellular arteries as vascular grafts.
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Affiliation(s)
- George Fercana
- 1 Biocompatibility and Tissue Regeneration Laboratories, Department of Bioengineering, Clemson University , Clemson, South Carolina
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Pennel T, Fercana G, Bezuidenhout D, Simionescu A, Chuang TH, Zilla P, Simionescu D. The performance of cross-linked acellular arterial scaffolds as vascular grafts; pre-clinical testing in direct and isolation loop circulatory models. Biomaterials 2014; 35:6311-22. [PMID: 24816365 DOI: 10.1016/j.biomaterials.2014.04.062] [Citation(s) in RCA: 52] [Impact Index Per Article: 5.2] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/14/2014] [Accepted: 04/16/2014] [Indexed: 11/18/2022]
Abstract
There is a significant need for small diameter vascular grafts to be used in peripheral vascular surgery; however autologous grafts are not always available, synthetic grafts perform poorly and allografts and xenografts degenerate, dilate and calcify after implantation. We hypothesized that chemical stabilization of acellular xenogenic arteries would generate off-the-shelf grafts resistant to thrombosis, dilatation and calcification. To test this hypothesis, we decellularized porcine renal arteries, stabilized elastin with penta-galloyl glucose and collagen with carbodiimide/activated heparin and implanted them as transposition grafts in the abdominal aorta of rats as direct implants and separately as indirect, isolation-loop implants. All implants resulted in high patency and animal survival rates, ubiquitous encapsulation within a vascularized collagenous capsule, and exhibited lack of lumen thrombogenicity and no graft wall calcification. Peri-anastomotic neo-intimal tissue overgrowth was a normal occurrence in direct implants; however this reaction was circumvented in indirect implants. Notably, implantation of non-treated control scaffolds exhibited marked graft dilatation and elastin degeneration; however PGG significantly reduced elastin degradation and prevented aneurismal dilatation of vascular grafts. Overall these results point to the outstanding potential of crosslinked arterial scaffolds as small diameter vascular grafts.
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Affiliation(s)
- Timothy Pennel
- Christian Barnard Department of Cardiothoracic Surgery, Cardiovascular Research Unit, University of Cape Town, Faculty of Health Sciences, Cape Heart Center, Chris Barnard Building, Anzio Road, ZA 7925 Observatory, Cape Town, South Africa
| | - George Fercana
- Biocompatibility and Tissue Regeneration Laboratories, Department of Bioengineering, Clemson University, Clemson, SC, USA
| | - Deon Bezuidenhout
- Christian Barnard Department of Cardiothoracic Surgery, Cardiovascular Research Unit, University of Cape Town, Faculty of Health Sciences, Cape Heart Center, Chris Barnard Building, Anzio Road, ZA 7925 Observatory, Cape Town, South Africa
| | - Agneta Simionescu
- Biocompatibility and Tissue Regeneration Laboratories, Department of Bioengineering, Clemson University, Clemson, SC, USA
| | - Ting-Hsien Chuang
- Biocompatibility and Tissue Regeneration Laboratories, Department of Bioengineering, Clemson University, Clemson, SC, USA
| | - Peter Zilla
- Christian Barnard Department of Cardiothoracic Surgery, Cardiovascular Research Unit, University of Cape Town, Faculty of Health Sciences, Cape Heart Center, Chris Barnard Building, Anzio Road, ZA 7925 Observatory, Cape Town, South Africa
| | - Dan Simionescu
- Biocompatibility and Tissue Regeneration Laboratories, Department of Bioengineering, Clemson University, Clemson, SC, USA.
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