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Wu F, Zhang W, Du Y, Cheng F, Li H. Tunable shape memory properties of highly stretchable poly(ester urea) random copolymers based on α-amino acids. SOFT MATTER 2022; 18:7959-7967. [PMID: 36214048 DOI: 10.1039/d2sm00936f] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/16/2023]
Abstract
The exploration of biodegradable polymers with shape memory effects (SMEs) holds great promise in biomedical fields. Revealing the relationship between the SMEs and polymer structures not only contributes to interpreting the SME mechanisms, but also prompts the customization of materials properties for specific requirements. Herein, we developed a series of poly(ester urea) (PEU) random copolymers composed of two different diamine monomers based on L-alanine and L-valine, respectively. It was shown that the shape memory performance of the PEU copolymers strongly depended on the composition of two different diamine monomers in the PEU copolymers and other physical properties. This tunability likely arose from the change of polymer chain mobility and crystallinity, which were impacted by the choice of α-amino acids. Intriguingly, thin films of the PEU copolymers exhibited a high strain at break of 347-743% around the physiological temperature (35 °C). Moreover, the random copolymerization of two different sorts of diamine monomers has been demonstrated as a facile approach to precisely tailor the physical properties of the PEUs according to custom needs.
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Affiliation(s)
- Fangyun Wu
- CNNC Nuclear Power Operations Management Co., Ltd, Haiyan, 314300, China
| | - Wei Zhang
- CNNC Nuclear Power Operations Management Co., Ltd, Haiyan, 314300, China
| | - Yanqiu Du
- College of Material and Textile Engineering, Nanotechnology Research Institute, Jiaxing University, Jiaxing, 314001, China.
| | - Fengmei Cheng
- College of Material and Textile Engineering, Nanotechnology Research Institute, Jiaxing University, Jiaxing, 314001, China.
| | - Haidong Li
- College of Material and Textile Engineering, Nanotechnology Research Institute, Jiaxing University, Jiaxing, 314001, China.
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2
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Preparation of Poly(ε-caprolactone)/Poly(ester amide) Electrospun Membranes for Vascular Repair. Chem Res Chin Univ 2022. [DOI: 10.1007/s40242-022-1480-8] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/13/2022]
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3
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Mohindra P, Desai TA. Micro- and nanoscale biophysical cues for cardiovascular disease therapy. NANOMEDICINE : NANOTECHNOLOGY, BIOLOGY, AND MEDICINE 2021; 34:102365. [PMID: 33571682 PMCID: PMC8217090 DOI: 10.1016/j.nano.2021.102365] [Citation(s) in RCA: 9] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 12/01/2020] [Accepted: 01/15/2021] [Indexed: 11/19/2022]
Abstract
After cardiovascular injury, numerous pathological processes adversely impact the homeostatic function of cardiomyocyte, macrophage, fibroblast, endothelial cell, and vascular smooth muscle cell populations. Subsequent malfunctioning of these cells may further contribute to cardiovascular disease onset and progression. By modulating cellular responses after injury, it is possible to create local environments that promote wound healing and tissue repair mechanisms. The extracellular matrix continuously provides these mechanosensitive cell types with physical cues spanning the micro- and nanoscale to influence behaviors such as adhesion, morphology, and phenotype. It is therefore becoming increasingly compelling to harness these cell-substrate interactions to elicit more native cell behaviors that impede cardiovascular disease progression and enhance regenerative potential. This review discusses recent in vitro and preclinical work that have demonstrated the therapeutic implications of micro- and nanoscale biophysical cues on cell types adversely affected in cardiovascular diseases - cardiomyocytes, macrophages, fibroblasts, endothelial cells, and vascular smooth muscle cells.
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Affiliation(s)
- Priya Mohindra
- UC Berkeley-UCSF Graduate Program in Bioengineering, San Francisco, CA, United States
| | - Tejal A Desai
- UC Berkeley-UCSF Graduate Program in Bioengineering, San Francisco, CA, United States; Department of Bioengineering and Therapeutic Sciences, University of California, San Francisco, San Francisco, CA, USA; Department of Bioengineering, University of California, Berkeley, Berkeley, CA.
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4
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Bai S, Zhang X, Zang L, Yang S, Chen X, Yuan X. Electrospinning of Biomaterials for Vascular Regeneration. Chem Res Chin Univ 2021. [DOI: 10.1007/s40242-021-1125-3] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/13/2022]
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5
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Kirillova A, Yeazel TR, Asheghali D, Petersen SR, Dort S, Gall K, Becker ML. Fabrication of Biomedical Scaffolds Using Biodegradable Polymers. Chem Rev 2021; 121:11238-11304. [PMID: 33856196 DOI: 10.1021/acs.chemrev.0c01200] [Citation(s) in RCA: 94] [Impact Index Per Article: 31.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/08/2023]
Abstract
Degradable polymers are used widely in tissue engineering and regenerative medicine. Maturing capabilities in additive manufacturing coupled with advances in orthogonal chemical functionalization methodologies have enabled a rapid evolution of defect-specific form factors and strategies for designing and creating bioactive scaffolds. However, these defect-specific scaffolds, especially when utilizing degradable polymers as the base material, present processing challenges that are distinct and unique from other classes of materials. The goal of this review is to provide a guide for the fabrication of biodegradable polymer-based scaffolds that includes the complete pathway starting from selecting materials, choosing the correct fabrication method, and considering the requirements for tissue specific applications of the scaffold.
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Affiliation(s)
- Alina Kirillova
- Thomas Lord Department of Mechanical Engineering and Materials Science, Duke University, Durham, North Carolina 27708, United States
| | - Taylor R Yeazel
- Thomas Lord Department of Mechanical Engineering and Materials Science, Duke University, Durham, North Carolina 27708, United States
| | - Darya Asheghali
- Department of Chemistry, Duke University, Durham, North Carolina 27708, United States
| | - Shannon R Petersen
- Department of Chemistry, Duke University, Durham, North Carolina 27708, United States
| | - Sophia Dort
- Department of Chemistry, Duke University, Durham, North Carolina 27708, United States
| | - Ken Gall
- Thomas Lord Department of Mechanical Engineering and Materials Science, Duke University, Durham, North Carolina 27708, United States
| | - Matthew L Becker
- Thomas Lord Department of Mechanical Engineering and Materials Science, Duke University, Durham, North Carolina 27708, United States.,Department of Chemistry, Duke University, Durham, North Carolina 27708, United States.,Departments of Biomedical Engineering and Orthopaedic Surgery, Duke University, Durham, North Carolina 27708, United States
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Kovylin RS, Aleynik DY, Fedushkin IL. Modern Porous Polymer Implants: Synthesis, Properties, and Application. POLYMER SCIENCE SERIES C 2021. [DOI: 10.1134/s1811238221010033] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/23/2022]
Abstract
Abstract
The needs of modern surgery triggered the intensive development of transplantology, medical materials science, and tissue engineering. These directions require the use of innovative materials, among which porous polymers occupy one of the leading positions. The use of natural and synthetic polymers makes it possible to adjust the structure and combination of properties of a material to its particular application. This review generalizes and systematizes the results of recent studies describing requirements imposed on the structure and properties of synthetic (or artificial) porous polymer materials and implants on their basis and the advantages and limitations of synthesis methods. The most extensively employed, promising initial materials are considered, and the possible areas of application of polymer implants based on these materials are highlighted.
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Matsuzaki Y, Iwaki R, Reinhardt JW, Chang YC, Miyamoto S, Kelly J, Zbinden J, Blum K, Mirhaidari G, Ulziibayar A, Shoji T, Breuer CK, Shinoka T. The effect of pore diameter on neo-tissue formation in electrospun biodegradable tissue-engineered arterial grafts in a large animal model. Acta Biomater 2020; 115:176-184. [PMID: 32822820 DOI: 10.1016/j.actbio.2020.08.011] [Citation(s) in RCA: 15] [Impact Index Per Article: 3.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/23/2020] [Revised: 07/31/2020] [Accepted: 08/04/2020] [Indexed: 02/06/2023]
Abstract
To date, there has been little investigation of biodegradable tissue engineered arterial grafts (TEAG) using clinically relevant large animal models. The purpose of this study is to explore how pore size of electrospun scaffolds can be used to balance neoarterial tissue formation with graft structural integrity under arterial environmental conditions throughout the remodeling process. TEAGs were created with an outer poly-ε-caprolactone (PCL) electrospun layer and an inner sponge layer composed of heparin conjugated 50:50 poly (l-lactide-co-ε-caprolactone) copolymer (PLCL). Outer electrospun layers were created with four different pore diameters (4, 7, 10, and 15 µm). Fourteen adult female sheep underwent bilateral carotid artery interposition grafting (n = 3-4 /group). Our heparin-eluting TEAG was implanted on one side (n = 14) and ePTFE graft (n = 3) or non-heparin-eluting TEAG (n = 5) on the other side. Twelve of the fourteen animals survived to the designated endpoint at 8 weeks, and one animal with 4 µm pore diameter graft was followed to 1 year. All heparin-eluting TEAGs were patent, but those with pore diameters larger than 4 µm began to dilate at week 4. Only scaffolds with a pore diameter of 4 µm resisted dilation and could do so for up to 1 year. At 8 weeks, the 10 µm pore graft had the highest density of cells in the electrospun layer and macrophages were the primary cell type present. This study highlights challenges in designing bioabsorbable TEAGs for the arterial environment in a large animal model. While larger pore diameter TEAGs promoted cell infiltration, neotissue could not regenerate rapidly enough to provide sufficient mechanical strength required to resist dilation. Future studies will be focused on evaluating a smaller pore design to better understand long-term remodeling and determine feasibility for clinical use. STATEMENT OF SIGNIFICANCE: In situ vascular tissue engineering relies on a biodegradable scaffold that encourages tissue regeneration and maintains mechanical integrity until the neotissue can bear the load. Species-specific differences in tissue regeneration and larger mechanical forces often result in graft failure when scaling up from small to large animal models. This study utilizes a slow-degrading electrospun PCL sheath to reinforce a tissue engineered arterials graft. Pore size, a property critical to tissue regeneration, was controlled by changing PCL fiber diameter and the resulting effects of these properties on neotissue formation and graft durability was evaluated. This study is among few to report the effect of pore size on vascular neotissue formation in a large animal arterial model and also demonstrate robust neotissue formation.
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Nikam SP, Nettleton K, Everitt JI, Barton HA, Becker ML. Antibiotic eluting poly(ester urea) films for control of a model cardiac implantable electronic device infection. Acta Biomater 2020; 111:65-79. [PMID: 32447067 DOI: 10.1016/j.actbio.2020.04.025] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/11/2020] [Revised: 04/05/2020] [Accepted: 04/13/2020] [Indexed: 02/07/2023]
Abstract
Cardiac implantable electronic device (CIED) infections acquired during or after surgical procedures are a major complication that are challenging to treat therapeutically, resulting in chronic and sometimes fatal infections. Localized delivery of antibiotics at the surgical site could be used to supplement traditional systemic administration as a preventative measure. Herein, we investigate a cefazolin-eluting l-valine poly(ester urea) (PEU) films as a model system for localized antibiotic delivery for CIEDs. Poly(1-VAL-8) PEU was used to fabricate a series of antibiotic-loaded films with varied loading concentrations (2%, 5%, 10% wt/wt) and thicknesses (40 µm, 80 µm, 140 µm). In vitro release measurements show thickness and loading concentration influence the amount and rate of cefazolin release. Group 10%-140 µm (load-thickness) showed 22.5% release of active pharmaceutical ingredient (API) in the first 24 h and 81.2% of cumulative percent release through day 14 and was found most effective in bacterial clearance in vitro. This group was also effective in clearing a bacterial infection in a model in vivo rat study while eliciting a limited inflammatory response. Our results suggest the feasibility of cefazolin-loaded PEU films as an effective sustained release matrix for localized delivery of antibiotics. SIGNIFICANCE STATEMENT: Implant-associated infections acquired during surgical procedures are a major complication that have proven a challenge to treat clinically, resulting in chronic and sometimes fatal infections. In this manuscript, we investigate an antibiotic-eluting L-valine poly(ester urea) (PEU) films as a model system for localized delivery of cefazolin. Significantly, we demonstrate a wide variation in temporal delivery and dosing within this family of PEUs and show that the delivery can be extended by varying the film thickness. The in vivo results show efficacy in an infected wound model and suggest antibiotic loaded PEU films function as an effective sustained release matrix for localized delivery of antibiotics across a number of clinical indications.
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Endothelialization of arterial vascular grafts by circulating monocytes. Nat Commun 2020; 11:1622. [PMID: 32238801 PMCID: PMC7113268 DOI: 10.1038/s41467-020-15361-2] [Citation(s) in RCA: 59] [Impact Index Per Article: 14.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/01/2019] [Accepted: 03/05/2020] [Indexed: 12/15/2022] Open
Abstract
Recently our group demonstrated that acellular tissue engineered vessels (A-TEVs) comprised of small intestinal submucosa (SIS) immobilized with heparin and vascular endothelial growth factor (VEGF) could be implanted into the arterial system of a pre-clinical ovine animal model, where they endothelialized within one month and remained patent. Here we report that immobilized VEGF captures blood circulating monocytes (MC) with high specificity under a range of shear stresses. Adherent MC differentiate into a mixed endothelial (EC) and macrophage (Mφ) phenotype and further develop into mature EC that align in the direction of flow and produce nitric oxide under high shear stress. In-vivo, newly recruited cells on the vascular lumen express MC markers and at later times they co-express MC and EC-specific proteins and maintain graft patency. This novel finding indicates that the highly prevalent circulating MC contribute directly to the endothelialization of acellular vascular grafts under the right chemical and biomechanical cues. Acellular tissue engineered vessels functionalised with VEGF are coated with a layer of endothelial cells after in vivo implantation, but the source of the cells are unknown. Here the authors provide evidence that monocytes expressing VEGF receptors can transdifferentiate into endothelial cells via a macrophage intermediate.
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10
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Li X, Xu J, Bartolák-Suki E, Jiang J, Tien J. Evaluation of 1-mm-diameter endothelialized dense collagen tubes in vascular microsurgery. J Biomed Mater Res B Appl Biomater 2020; 108:2441-2449. [PMID: 32017412 DOI: 10.1002/jbm.b.34576] [Citation(s) in RCA: 10] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/24/2019] [Revised: 01/08/2020] [Accepted: 01/19/2020] [Indexed: 11/08/2022]
Abstract
Although much progress has been made in engineering vascular grafts for large- and small-diameter arterial repair or bypass, the extension of these results to the microsurgical size scale has been challenging. Here, we evaluated the use of dense collagen tubes (outer diameter 1 mm, inner diameter 0.5 mm) for vascular microsurgery as interpositional grafts to the femoral artery of Lewis rats. These tubes were formed by dehydrating tubular collagen gels around a mandrel, crosslinking them with genipin, seeding with syngeneic endothelial cells, and culturing before implantation by suture anastomosis. The retention of a confluent endothelial lining inside the tubes after mock surgical handling depended strongly on the crosslinker concentration and culture time. Optimized preparation conditions enabled retention of endothelium after mock surgical handling in ~80% of tubes and maintenance of patency 7 days after implantation in ~40% of grafts. Histological analysis showed the development of granulation tissue and the presence of CD31-positive structures on the inner and outer surfaces of implants. This study provides a proof-of-principle demonstration that endothelialized dense collagen tubes can remain patent for up to 7 days after vascular microsurgery, and points to the importance of mild scaffold crosslinking for maintaining firm endothelial adhesion.
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Affiliation(s)
- Xuanyue Li
- Department of Biomedical Engineering, Boston University, Boston, Massachusetts
| | - Jing Xu
- Department of Biomedical Engineering, Boston University, Boston, Massachusetts
| | | | - John Jiang
- Department of Biomedical Engineering, Boston University, Boston, Massachusetts
| | - Joe Tien
- Department of Biomedical Engineering, Boston University, Boston, Massachusetts.,Division of Materials Science and Engineering, Boston University, Boston, Massachusetts
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11
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Yang Y, Lei D, Zou H, Huang S, Yang Q, Li S, Qing FL, Ye X, You Z, Zhao Q. Hybrid electrospun rapamycin-loaded small-diameter decellularized vascular grafts effectively inhibit intimal hyperplasia. Acta Biomater 2019; 97:321-332. [PMID: 31523025 DOI: 10.1016/j.actbio.2019.06.037] [Citation(s) in RCA: 46] [Impact Index Per Article: 9.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/03/2019] [Revised: 06/16/2019] [Accepted: 06/21/2019] [Indexed: 12/16/2022]
Abstract
For the surgical treatment of coronary artery disease, renal artery stenosis and other peripheral vascular diseases, there is significant demand for small diameter (inner diameter <6 mm) vascular grafts. However, autologous grafts are not always available when the substitute vascular grafts are severely diseased. In our previous work, hybrid small-diameter vascular grafts were successfully fabricated by combining electrospun polycaprolactone (PCL) and decellularized rat aorta (DRA). However, histological assessments of these grafts revealed the development of intimal hyperplasia, indicating potential negative impacts on the long-term patency of these grafts. To address this challenge, PCL nanofibers blended with rapamycin (RM) were electrospun outside the decellularized vascular graft to fabricate a RM-loaded hybrid tissue-engineered vascular graft (RM-HTEV), endowing the graft with a drug delivery function to prevent intimal hyperplasia. RM-HTEV possessed superior mechanical properties compared to DRA and exhibited a sustained drug release profile. To evaluate the applicability of RM-HTEV in vivo, abdominal aorta transplantation was performed on rats. Doppler sonography showed that the grafts were functional for up to 8 weeks in vivo. Moreover, histological analysis of explanted grafts 12 weeks postimplantation demonstrated that RM-HTEV significantly decreased neo-intimal hyperplasia compared with HTEV, without impairing reendothelialization and M2 macrophage polarization. Overall, RM-HTEV represents a promising strategy for developing small-diameter vascular grafts with great clinical translational potential. STATEMENT OF SIGNIFICANCE: In this study, a new type of rapamycin-loaded hybrid tissue-engineered vascular graft (RM-HTEV) was fabricated using electrospinning technology. The unique hybrid bi-layer structure endowed the RM-HTEV with multi-functionality: the exterior rapamycin-loaded electrospun PCL nanofibrous layer enhanced the mechanical properties of the graft and possessed drug releasing property; the interior decellularized aorta layer with porous structure could facilitate cell proliferation and migration. In in vivo implantation experiment, RM-HTEV exhibited satisfying long-term patency rate and significantly inhibited intimal hyperplasia without impairing re-endothelialization and M2 macrophage polarization. This strategy is expected to be a promising strategy for developing bioactive small-diameter vascular grafts with great clinical translational potential.
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12
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Dreger NZ, Zander ZK, Hsu YH, Luong D, Chen P, Le N, Parsell T, Søndergaard C, Dunbar ML, Koewler NJ, Suckow MA, Becker ML. Zwitterionic amino acid-based Poly(ester urea)s suppress adhesion formation in a rat intra-abdominal cecal abrasion model. Biomaterials 2019; 221:119399. [PMID: 31421314 DOI: 10.1016/j.biomaterials.2019.119399] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/11/2019] [Revised: 07/29/2019] [Accepted: 07/29/2019] [Indexed: 12/16/2022]
Abstract
Hernia repair outcomes have improved with more robust material options for surgeons and optimized surgical techniques. However, ventral hernia repairs remain challenging with an inherent risk of post-surgical adhesions in the peritoneal space which can occur regardless of interventional material or its surgical placement. Herein, amino acid-based poly(ester urea)s (PEUs) with varied amount of an allyl ether side chains were modified post polymerization modification with the zwitterionic sulfnate group (3-((3-((3-mercaptopropanoyl)oxy)propyl) dimethylammonio)propane-1-sulfonate) to promote anti-adhesive properties. These alloc-PEUs were processed using roll-to-roll fabrication methods to afford films that were amenable to surface functionalization via a zwitterion-thiol. Functional group availability on the surface was confirmed via fluorescence microscopy, x-ray photoelectron spectroscopy (XPS), and quartz crystal microbalance (QCM) measurements. Zwitterionic treated PEUs exhibited reduced fibrinogen adsorption in vitro when compared to unfunctionalized control polymer. A rat intrabdominal cecal abrasion adhesion model was used to assess the extent and tenacity of adhesion formation in the presence of the PEUs. The 10% alloc-PEU zwitterion functionalized material was found to reduce the extent and tenacity of adhesions when compared to adhesion controls and the unfunctionalized PEU controls.
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Affiliation(s)
- Nathan Z Dreger
- Department of Polymer Science, The University of Akron, Akron, OH, 44325, USA
| | - Zachary K Zander
- Department of Polymer Science, The University of Akron, Akron, OH, 44325, USA
| | - Yen-Hao Hsu
- Department of Polymer Science, The University of Akron, Akron, OH, 44325, USA
| | - Derek Luong
- Department of Polymer Science, The University of Akron, Akron, OH, 44325, USA
| | - Peiru Chen
- Department of Polymer Science, The University of Akron, Akron, OH, 44325, USA
| | - Nancy Le
- Department of Polymer Science, The University of Akron, Akron, OH, 44325, USA
| | | | | | - Misha L Dunbar
- College of Veterinary Medicine, The University of Minnesota, Minneapolis, MN, 55455, USA
| | - Nathan J Koewler
- College of Veterinary Medicine, The University of Minnesota, Minneapolis, MN, 55455, USA
| | - Mark A Suckow
- Department of Biomedical Engineering, The University of Kentucky, Lexington, KY, 40506, USA
| | - Matthew L Becker
- Department of Polymer Science, The University of Akron, Akron, OH, 44325, USA; Biomedical Engineering, The University of Akron, Akron, OH, 44325, USA; Department of Chemistry, Duke University, Durham, NC, 27708, USA; Department of Mechanical Engineering and Material Science, Duke University, Durham, NC, 27708, USA; Orthopaedic Surgery, Duke University, Durham, NC, 27708, USA.
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13
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Cai Z, Wan Y, Becker ML, Long YZ, Dean D. Poly(propylene fumarate)-based materials: Synthesis, functionalization, properties, device fabrication and biomedical applications. Biomaterials 2019; 208:45-71. [PMID: 30991217 DOI: 10.1016/j.biomaterials.2019.03.038] [Citation(s) in RCA: 54] [Impact Index Per Article: 10.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/21/2018] [Revised: 03/04/2019] [Accepted: 03/23/2019] [Indexed: 12/22/2022]
Abstract
Poly(propylene fumarate) (PPF) is a biodegradable polymer that has been investigated extensively over the last three decades. It has led many scientists to synthesize and fabricate a variety of PPF-based materials for biomedical applications due to its controllable mechanical properties, tunable degradation and biocompatibility. This review provides a comprehensive overview of the progress made in improving PPF synthesis, resin formulation, crosslinking, device fabrication and post polymerization modification. Further, we highlight the influence of these parameters on biodegradation, biocompatibility, and their use in a number of regenerative medicine applications, especially bone tissue engineering. In particular, the use of 3D printing techniques for the fabrication of PPF-based scaffolds is extensively reviewed. The recent invention of a ring-opening polymerization method affords precise control of PPF molecular mass, molecular mass distribution (ƉM) and viscosity. Low ƉM facilitates time-certain resorption of 3D printed structures. Novel post-polymerization and post-printing functionalization methods have accelerated the expansion of biomedical applications that utilize PPF-based materials. Finally, we shed light on evolving uses of PPF-based materials for orthopedics/bone tissue engineering and other biomedical applications, including its use as a hydrogel for bioprinting.
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Affiliation(s)
- Zhongyu Cai
- Department of Chemical and Biomolecular Engineering, National University of Singapore, 4 Engineering Drive 4, 117585, Singapore; Department of Chemistry, University of Pittsburgh, Chevron Science Center, 219 Parkman Avenue, Pittsburgh, PA 15260, United States.
| | - Yong Wan
- Collaborative Innovation Center for Nanomaterials, College of Physics, Qingdao University, No. 308 Ningxia Road, Qingdao, 266071, Shandong Province, China
| | - Matthew L Becker
- Department of Polymer Science, The University of Akron, Akron, OH 44325, United States
| | - Yun-Ze Long
- Collaborative Innovation Center for Nanomaterials, College of Physics, Qingdao University, No. 308 Ningxia Road, Qingdao, 266071, Shandong Province, China; Industrial Research Institute of Nonwovens & Technical Textiles, Qingdao University, No. 308 Ningxia Road, Qingdao, 266071, Shandong Province, China.
| | - David Dean
- Department of Plastic & Reconstructive Surgery, The Ohio State University, Columbus, OH 43210, United States.
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Preparation of a biomimetic ECM surface on cardiovascular biomaterials via a novel layer-by-layer decellularization for better biocompatibility. MATERIALS SCIENCE & ENGINEERING. C, MATERIALS FOR BIOLOGICAL APPLICATIONS 2019; 96:509-521. [DOI: 10.1016/j.msec.2018.11.078] [Citation(s) in RCA: 24] [Impact Index Per Article: 4.8] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Received: 01/04/2018] [Revised: 11/07/2018] [Accepted: 11/29/2018] [Indexed: 12/21/2022]
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15
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Dharmadhikari S, Best CA, King N, Henderson M, Johnson J, Breuer CK, Chiang T. Mouse Model of Tracheal Replacement With Electrospun Nanofiber Scaffolds. Ann Otol Rhinol Laryngol 2019; 128:391-400. [PMID: 30700095 DOI: 10.1177/0003489419826134] [Citation(s) in RCA: 11] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/22/2023]
Abstract
OBJECTIVES The clinical experience with tissue-engineered tracheal grafts (TETGs) has been fraught with graft stenosis and delayed epithelialization. A mouse model of orthotopic replacement that recapitulates the clinical findings would facilitate the study of the cellular and molecular mechanisms underlying graft stenosis. METHODS Electrospun nanofiber tracheal scaffolds were created using nonresorbable (polyethylene terephthalate + polyurethane) and co-electrospun resorbable (polylactide-co-caprolactone/polyglycolic acid) polymers (n = 10/group). Biomechanical testing was performed to compare load displacement of nanofiber scaffolds to native mouse tracheas. Mice underwent orthotopic tracheal replacement with syngeneic grafts (n = 5) and nonresorbable (n = 10) and resorbable (n = 10) scaffolds. Tissue at the anastomosis was evaluated using hematoxylin and eosin (H&E), K5+ basal cells were evaluated with the help of immunofluorescence testing, and cellular infiltration of the scaffold was quantified. Micro computed tomography was performed to assess graft patency and correlate radiographic and histologic findings with respiratory symptoms. RESULTS Synthetic scaffolds were supraphysiologic in compression tests compared to native mouse trachea ( P < .0001). Nonresorbable scaffolds were stiffer than resorbable scaffolds ( P = .0004). Eighty percent of syngeneic recipients survived to the study endpoint of 60 days postoperatively. Mean survival with nonresorbable scaffolds was 11.40 ± 7.31 days and 6.70 ± 3.95 days with resorbable scaffolds ( P = .095). Stenosis manifested with tissue overgrowth in nonresorbable scaffolds and malacia in resorbable scaffolds. Quantification of scaffold cellular infiltration correlated with length of survival in resorbable scaffolds (R2 = 0.95, P = .0051). Micro computed tomography demonstrated the development of graft stenosis at the distal anastomosis on day 5 and progressed until euthanasia was performed on day 11. CONCLUSION Graft stenosis seen in orthotopic tracheal replacement with synthetic tracheal scaffolds can be modeled in mice. The wide array of lineage tracing and transgenic mouse models available will permit future investigation of the cellular and molecular mechanisms underlying TETG stenosis.
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Affiliation(s)
- Sayali Dharmadhikari
- 1 Center for Regenerative Medicine, Research Institute at Nationwide Children's Hospital, Columbus, Ohio, USA.,2 Department of Otolaryngology, Nationwide Children's Hospital, Columbus, Ohio, USA
| | - Cameron A Best
- 1 Center for Regenerative Medicine, Research Institute at Nationwide Children's Hospital, Columbus, Ohio, USA.,3 Biomedical Sciences Graduate Program, The Ohio State University College of Medicine, Columbus, Ohio, USA
| | - Nakesha King
- 4 Department of General Surgery, The Ohio State University, Columbus, Ohio, USA
| | | | - Jed Johnson
- 5 Nanofiber Solutions, Inc, Hilliard, Ohio, USA
| | - Christopher K Breuer
- 1 Center for Regenerative Medicine, Research Institute at Nationwide Children's Hospital, Columbus, Ohio, USA.,6 Department of Pediatric Surgery, Nationwide Children's Hospital, Columbus, Ohio, USA
| | - Tendy Chiang
- 1 Center for Regenerative Medicine, Research Institute at Nationwide Children's Hospital, Columbus, Ohio, USA.,2 Department of Otolaryngology, Nationwide Children's Hospital, Columbus, Ohio, USA
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16
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Smith RJ, Yi T, Nasiri B, Breuer CK, Andreadis ST. Implantation of VEGF-functionalized cell-free vascular grafts: regenerative and immunological response. FASEB J 2019; 33:5089-5100. [PMID: 30629890 DOI: 10.1096/fj.201801856r] [Citation(s) in RCA: 23] [Impact Index Per Article: 4.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/19/2023]
Abstract
Recently, our group demonstrated that immobilized VEGF can capture flowing endothelial cells (ECs) from the blood in vitro and promote endothelialization and patency of acellular tissue-engineered vessels (A-TEVs) into the arterial system of an ovine animal model. Here, we demonstrate implantability of submillimeter diameter heparin and VEGF-decorated A-TEVs in a mouse model and discuss the cellular and immunologic response. At 1 mo postimplantation, the graft lumen was fully endothelialized, as shown by expression of EC markers such as CD144, eNOS, CD31, and VEGFR2. Interestingly, the same cells coexpressed leukocyte/macrophage (Mϕ) markers CD14, CD16, VEGFR1, CD38, and EGR2. Notably, there was a stark difference in the cellular makeup between grafts containing VEGF and those containing heparin alone. In VEGF-containing grafts, infiltrating monocytes (MCs) converted into anti-inflammatory M2-Mϕs, and the grafts developed well-demarcated luminal and medial layers resembling those of native arteries. In contrast, in grafts containing only heparin, MCs converted primarily into M1-Mϕs, and the endothelial and smooth muscle layers were not well defined. Our results indicate that VEGF may play an important role in regulating A-TEV patency and regeneration, possibly by regulating the inflammatory response to the implants.-Smith, R. J., Jr., Yi, T., Nasiri, B., Breuer, C. K., Andreadis, S. T. Implantation of VEGF-functionalized cell-free vascular grafts: regenerative and immunological response.
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Affiliation(s)
- Randall J Smith
- Department of Biomedical Engineering, University at Buffalo, State University of New York, Amherst, New York, USA
| | - Tai Yi
- Nationwide Children's Hospital, Columbus, Ohio, USA
| | - Bita Nasiri
- Department of Chemical and Biological Engineering, University at Buffalo, State University of New York, Amherst, New York, USA; and
| | | | - Stelios T Andreadis
- Department of Biomedical Engineering, University at Buffalo, State University of New York, Amherst, New York, USA.,Department of Chemical and Biological Engineering, University at Buffalo, State University of New York, Amherst, New York, USA; and.,Center of Excellence in Bioinformatics and Life Sciences, University at Buffalo, State University of New York, Amherst, New York, USA
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Cai K, Ying H, Cheng J. Dynamic Ureas with Fast and pH-Independent Hydrolytic Kinetics. Chemistry 2018; 24:7345-7348. [PMID: 29624762 DOI: 10.1002/chem.201801138] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/06/2018] [Revised: 03/29/2018] [Indexed: 12/13/2022]
Abstract
Low cost, high performance hydrolysable polymers are of great importance in biomedical applications and materials industries. While many applications require materials to have a degradation profile insensitive to external pH to achieve consistent release profiles under varying conditions, hydrolysable chemistry techniques developed so far have pH-dependent hydrolytic kinetics. This work reports the design and synthesis of a new type of hydrolysable polymer that has identical hydrolysis kinetics from pH 3 to 11. The unprecedented pH independent hydrolytic kinetics of the aryl ureas were shown to be related to the dynamic bond dissociation controlled hydrolysis mechanism; the resulting hindered poly(aryl urea) can be degraded with a hydrolysis half-life of 10 min in solution. More importantly, these fast degradable hindered aromatic polyureas can be easily prepared by addition polymerization from commercially available monomers and are resistant to hydrolysis in solid form for months under ambient storage conditions. The combined features of good stability in solid state and fast hydrolysis at various pH values is unprecedented in polyurea material, and will have implications for materials design and applications, such as sacrificial coatings and biomaterials.
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Affiliation(s)
- Kaimin Cai
- Department of Materials Science and Engineering, 1304 W. Green St., Urbana, IL 61801, USA
| | - Hanze Ying
- Department of Materials Science and Engineering, 1304 W. Green St., Urbana, IL 61801, USA
| | - Jianjun Cheng
- Department of Materials Science and Engineering, 1304 W. Green St., Urbana, IL 61801, USA.,Department of Bioengineering, University of Illinois at Urbana-Champaign, Urbana, IL, 61801, USA.,Department of Chemistry, University of Illinois at Urbana-Champaign, Urbana, IL, 61801, USA.,Beckman Institute for Advanced Science and Technology, University of Illinois at Urbana-Champaign, Urbana, IL, 61801, USA.,Micro and Nanotechnology Laboratory, University of Illinois at Urbana-Champaign, Urbana, IL, 61801, USA.,Carl R. Woese Institute for Genomic Biology, University of Illinois at Urbana-Champaign, Urbana, IL, 61801, USA.,Materials Research Laboratory, University of Illinois at Urbana-Champaign, Urbana, IL, 61801, USA
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18
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Aydogdu MO, Chou J, Altun E, Ekren N, Cakmak S, Eroglu M, Osman AA, Kutlu O, Oner ET, Avsar G, Oktar FN, Yilmaz I, Gunduz O. Production of the biomimetic small diameter blood vessels for cardiovascular tissue engineering. INT J POLYM MATER PO 2018. [DOI: 10.1080/00914037.2018.1443930] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/08/2023]
Affiliation(s)
- Mehmet Onur Aydogdu
- Advanced Nanomaterials Research Laboratory, Department of Metallurgical and Materials Engineering, Marmara University, Istanbul, Turkey
- Department of Metallurgical and Materials Engineering, Master of Science, Institute of Pure and Applied Sciences, Marmara University, Istanbul, Turkey
| | - Joshua Chou
- Advanced Tissue Regeneration and Drug Delivery Group, School of Medical and Molecular Sciences, University of Technology Sydney, Sydney, NSW, Australia
| | - Esra Altun
- Advanced Nanomaterials Research Laboratory, Department of Metallurgical and Materials Engineering, Marmara University, Istanbul, Turkey
- Department of Metallurgical and Materials Engineering, Master of Science, Institute of Pure and Applied Sciences, Marmara University, Istanbul, Turkey
| | - Nazmi Ekren
- Advanced Nanomaterials Research Laboratory, Department of Metallurgical and Materials Engineering, Marmara University, Istanbul, Turkey
- Department of Electrical and Electronics Engineering, Faculty of Technology, Marmara University, Istanbul, Turkey
| | - Selami Cakmak
- Orthopedics and Traumatology Clinic, Acibadem Kadikoy Hospital, Istanbul, Turkey
| | - Mehmet Eroglu
- Department of Chemical Engineering, Faculty of Engineering, Marmara University, Istanbul, Turkey
| | - Asila A. Osman
- Department of Chemical Engineering, Faculty of Engineering, Marmara University, Istanbul, Turkey
| | - Ozlem Kutlu
- Nanotechnology Research and Application Center, & (EFSUN) Center of Excellence for Functional Surfaces and Interfaces for Nano Diagnostics, Sabanci University, Istanbul, Turkey
| | - Ebru Toksoy Oner
- Department of Bioengineering, Faculty of Engineering, Marmara University, Istanbul, Turkey
| | - Gulben Avsar
- Department of Bioengineering, Faculty of Engineering, Marmara University, Istanbul, Turkey
| | - Faik Nuzhet Oktar
- Advanced Nanomaterials Research Laboratory, Department of Metallurgical and Materials Engineering, Marmara University, Istanbul, Turkey
- Department of Bioengineering, Faculty of Engineering, Marmara University, Istanbul, Turkey
| | - Ismail Yilmaz
- Pathology Department, Istanbul Sultan Abdulhamid Han Training Hospital, Istanbul, Turkey
| | - Oguzhan Gunduz
- Advanced Nanomaterials Research Laboratory, Department of Metallurgical and Materials Engineering, Marmara University, Istanbul, Turkey
- Department of Metallurgical and Materials Engineering, Master of Science, Institute of Pure and Applied Sciences, Marmara University, Istanbul, Turkey
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Dreger NZ, Wandel MB, Robinson LL, Luong D, Søndergaard CS, Hiles M, Premanandan C, Becker ML. Preclinical in Vitro and in Vivo Assessment of Linear and Branched l-Valine-Based Poly(ester urea)s for Soft Tissue Applications. ACS Biomater Sci Eng 2018; 4:1346-1356. [PMID: 33418665 DOI: 10.1021/acsbiomaterials.7b00920] [Citation(s) in RCA: 10] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/29/2022]
Affiliation(s)
| | | | | | | | | | - Michael Hiles
- Cook Biotech Incorporated, West Lafayette, Indiana 47906, United States
| | - Christopher Premanandan
- Department of Veterinary Biosciences, College of Veterinary Medicine, The Ohio State University, Columbus, Ohio 43210, United States
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Li W, Chen J, Xu P, Zhu M, Wu Y, Wang Z, Zhao T, Cheng Q, Wang K, Fan G, Zhu Y, Kong D. Long-term evaluation of vascular grafts with circumferentially aligned microfibers in a rat abdominal aorta replacement model. J Biomed Mater Res B Appl Biomater 2018; 106:2596-2604. [PMID: 29412507 DOI: 10.1002/jbm.b.34076] [Citation(s) in RCA: 22] [Impact Index Per Article: 3.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/18/2017] [Revised: 12/19/2017] [Accepted: 12/31/2017] [Indexed: 12/22/2022]
Abstract
Long-term results of implants in small animal models can be used to optimize the design of grafts to further promote tissue regeneration. In previous study, we fabricated a poly(ɛ-caprolactone) (PCL) bi-layered vascular graft consisting of an internal layer with circumferentially aligned microfibers and an external layer with random nanofibers. The circumferentially oriented vascular smooth muscle cells (VSMCs) were successfully regenerated after the grafts were implanted in rat abdominal aorta for 3 months. Here we investigated the long-term (18 months) performance of the bi-layered grafts in the same model. All the grafts were patent. No thrombosis, aneurysm, or stenosis occurred. The endothelium maintained complete. However, most of circumferentially oriented VSMCs migrated to luminal surface of the grafts to form a neointima with uniform thickness. Accordingly, extracellular matrix including collagen, elastin, and glycosaminoglycan displayed high density in neointima layer while with low density in the grafts wall because of the incomplete degradation of PCL. A small amounts of calcification occurred in the grafts. The contraction and relaxation function of regenerated neoartery almost disappeared. These data indicated that based on the structure design, many other factors of grafts should be considered to achieve the regenerated neoartery similar to the native vessels after long-term implantation. © 2018 Wiley Periodicals, Inc. J Biomed Mater Res Part B: Appl Biomater, 106B: 2596-2604, 2018.
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Affiliation(s)
- Wen Li
- State Key Laboratory of Medicinal Chemical Biology, Key Laboratory of Bioactive Materials of Ministry of Education, College of Life Science, Nankai University, Tianjin, 300071, People's Republic of China
| | - Jingrui Chen
- Tianjin State Key Laboratory of Modern Chinese Medicine, Tianjin University of Traditional Chinese Medicine, Tianjin, 300193, People's Republic of China
| | - Pan Xu
- State Key Laboratory of Medicinal Chemical Biology, Key Laboratory of Bioactive Materials of Ministry of Education, College of Life Science, Nankai University, Tianjin, 300071, People's Republic of China
| | - Meifeng Zhu
- State Key Laboratory of Medicinal Chemical Biology, Key Laboratory of Bioactive Materials of Ministry of Education, College of Life Science, Nankai University, Tianjin, 300071, People's Republic of China
| | - Yifan Wu
- State Key Laboratory of Medicinal Chemical Biology, Key Laboratory of Bioactive Materials of Ministry of Education, College of Life Science, Nankai University, Tianjin, 300071, People's Republic of China
| | - Zhihong Wang
- Tianjin Key Laboratory of Biomaterial Research, Institute of Biomedical Engineering, Chinese Academy of Medical Sciences and Peking Union Medical College, Tianjin, 300192, People's Republic of China
| | - Tiechan Zhao
- Tianjin State Key Laboratory of Modern Chinese Medicine, Tianjin University of Traditional Chinese Medicine, Tianjin, 300193, People's Republic of China
| | - Quhan Cheng
- State Key Laboratory of Medicinal Chemical Biology, Key Laboratory of Bioactive Materials of Ministry of Education, College of Life Science, Nankai University, Tianjin, 300071, People's Republic of China
| | - Kai Wang
- State Key Laboratory of Medicinal Chemical Biology, Key Laboratory of Bioactive Materials of Ministry of Education, College of Life Science, Nankai University, Tianjin, 300071, People's Republic of China
| | - Guanwei Fan
- Tianjin State Key Laboratory of Modern Chinese Medicine, Tianjin University of Traditional Chinese Medicine, Tianjin, 300193, People's Republic of China
| | - Yan Zhu
- Tianjin State Key Laboratory of Modern Chinese Medicine, Tianjin University of Traditional Chinese Medicine, Tianjin, 300193, People's Republic of China
| | - Deling Kong
- State Key Laboratory of Medicinal Chemical Biology, Key Laboratory of Bioactive Materials of Ministry of Education, College of Life Science, Nankai University, Tianjin, 300071, People's Republic of China
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21
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Fukunishi T, Best CA, Ong CS, Groehl T, Reinhardt J, Yi T, Miyachi H, Zhang H, Shinoka T, Breuer CK, Johnson J, Hibino N. Role of Bone Marrow Mononuclear Cell Seeding for Nanofiber Vascular Grafts. Tissue Eng Part A 2017; 24:135-144. [PMID: 28486019 DOI: 10.1089/ten.tea.2017.0044] [Citation(s) in RCA: 32] [Impact Index Per Article: 4.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/05/2023] Open
Abstract
OBJECTIVE Electrospinning is a promising technology that provides biodegradable nanofiber scaffolds for cardiovascular tissue engineering. However, success with these materials has been limited, and the optimal combination of scaffold parameters for a tissue-engineered vascular graft (TEVG) remains elusive. The purpose of the present study is to evaluate the effect of bone marrow mononuclear cell (BM-MNC) seeding in electrospun scaffolds to support the rational design of optimized TEVGs. METHODS Nanofiber scaffolds were fabricated from co-electrospinning a solution of polyglycolic acid and a solution of poly(ι-lactide-co-ɛ-caprolactone) and characterized with scanning electron microscopy. Platelet activation and cell seeding efficiency were assessed by ATP secretion and DNA assays, respectively. Cell-free and BM-MNC seeded scaffolds were implanted in C57BL/6 mice (n = 15/group) as infrarenal inferior vena cava (IVC) interposition conduits. Animals were followed with serial ultrasonography for 6 months, after which grafts were harvested for evaluation of patency and neotissue formation by histology and immunohistochemistry (n = 10/group) and PCR (n = 5/group) analyses. RESULTS BM-MNC seeding of electrospun scaffolds prevented stenosis compared with unseeded scaffolds (seeded: 9/10 patent vs. unseeded: 1/10 patent, p = 0.0003). Seeded vascular grafts demonstrated concentric laminated smooth muscle cells, a confluent endothelial monolayer, and a collagen-rich extracellular matrix. Platelet-derived ATP, a marker of platelet activation, was significantly reduced after incubating thrombin-activated platelets in the presence of seeded scaffolds compared with unseeded scaffolds (p < 0.0001). In addition, reduced macrophage infiltration and a higher M2 macrophage percentage were observed in seeded grafts. CONCLUSIONS The beneficial effects of BM-MNC seeding apply to electrospun TEVG scaffolds by attenuating stenosis through the regulation of platelet activation and inflammatory macrophage function, leading to well-organized neotissue formation. BM-MNC seeding is a valuable technique that can be used in the rational design of optimal TEVG scaffolds.
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Affiliation(s)
- Takuma Fukunishi
- 1 Department of Cardiac Surgery, Johns Hopkins University , Baltimore, Maryland
| | - Cameron A Best
- 2 Tissue Engineering and Surgical Research, Nationwide Children's Hospital , Columbus, Ohio
| | - Chin Siang Ong
- 1 Department of Cardiac Surgery, Johns Hopkins University , Baltimore, Maryland
| | | | - James Reinhardt
- 2 Tissue Engineering and Surgical Research, Nationwide Children's Hospital , Columbus, Ohio
| | - Tai Yi
- 2 Tissue Engineering and Surgical Research, Nationwide Children's Hospital , Columbus, Ohio
| | - Hideki Miyachi
- 2 Tissue Engineering and Surgical Research, Nationwide Children's Hospital , Columbus, Ohio
| | - Huaitao Zhang
- 1 Department of Cardiac Surgery, Johns Hopkins University , Baltimore, Maryland
| | - Toshiharu Shinoka
- 2 Tissue Engineering and Surgical Research, Nationwide Children's Hospital , Columbus, Ohio
| | - Christopher K Breuer
- 2 Tissue Engineering and Surgical Research, Nationwide Children's Hospital , Columbus, Ohio
| | - Jed Johnson
- 3 Nanofiber Solutions, Inc. , Columbus, Ohio
| | - Narutoshi Hibino
- 1 Department of Cardiac Surgery, Johns Hopkins University , Baltimore, Maryland
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