1
|
Rahimnejad M, Makkar H, Dal-Fabbro R, Malda J, Sriram G, Bottino MC. Biofabrication Strategies for Oral Soft Tissue Regeneration. Adv Healthc Mater 2024:e2304537. [PMID: 38529835 DOI: 10.1002/adhm.202304537] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/19/2023] [Revised: 03/01/2024] [Indexed: 03/27/2024]
Abstract
Gingival recession, a prevalent condition affecting the gum tissues, is characterized by the exposure of tooth root surfaces due to the displacement of the gingival margin. This review explores conventional treatments, highlighting their limitations and the quest for innovative alternatives. Importantly, it emphasizes the critical considerations in gingival tissue engineering leveraging on cells, biomaterials, and signaling factors. Successful tissue-engineered gingival constructs hinge on strategic choices such as cell sources, scaffold design, mechanical properties, and growth factor delivery. Unveiling advancements in recent biofabrication technologies like 3D bioprinting, electrospinning, and microfluidic organ-on-chip systems, this review elucidates their precise control over cell arrangement, biomaterials, and signaling cues. These technologies empower the recapitulation of microphysiological features, enabling the development of gingival constructs that closely emulate the anatomical, physiological, and functional characteristics of native gingival tissues. The review explores diverse engineering strategies aiming at the biofabrication of realistic tissue-engineered gingival grafts. Further, the parallels between the skin and gingival tissues are highlighted, exploring the potential transfer of biofabrication approaches from skin tissue regeneration to gingival tissue engineering. To conclude, the exploration of innovative biofabrication technologies for gingival tissues and inspiration drawn from skin tissue engineering look forward to a transformative era in regenerative dentistry with improved clinical outcomes.
Collapse
Affiliation(s)
- Maedeh Rahimnejad
- Department of Cariology, Restorative Sciences, and Endodontics, School of Dentistry, University of Michigan, Ann Arbor, MI, 48109, USA
| | - Hardik Makkar
- Faculty of Dentistry, National University of Singapore, Singapore, 119085, Singapore
| | - Renan Dal-Fabbro
- Department of Cariology, Restorative Sciences, and Endodontics, School of Dentistry, University of Michigan, Ann Arbor, MI, 48109, USA
| | - Jos Malda
- Regenerative Medicine Center Utrecht, Utrecht, 3584, The Netherlands
- Department of Clinical Sciences, Faculty of Veterinary Medicine, Utrecht University, Utrecht, 3584, The Netherlands
- Department of Orthopedics, University Medical Center Utrecht, Utrecht, 3584, The Netherlands
| | - Gopu Sriram
- Faculty of Dentistry, National University of Singapore, Singapore, 119085, Singapore
- NUS Centre for Additive Manufacturing (AM.NUS), National University of Singapore, Singapore, 117597, Singapore
- Department of Biomedical Engineering, National University of Singapore, Singapore, 117583, Singapore
| | - Marco C Bottino
- Department of Cariology, Restorative Sciences, and Endodontics, School of Dentistry, University of Michigan, Ann Arbor, MI, 48109, USA
- Department of Biomedical Engineering, College of Engineering, University of Michigan, Ann Arbor, MI, 48109, USA
| |
Collapse
|
2
|
Recent advances in electrospun protein fibers/nanofibers for the food and biomedical applications. Adv Colloid Interface Sci 2023; 311:102827. [PMID: 36584601 DOI: 10.1016/j.cis.2022.102827] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/16/2022] [Revised: 12/12/2022] [Accepted: 12/14/2022] [Indexed: 12/29/2022]
Abstract
Electrospinning (ES) is one of the most investigated processes for the convenient, adaptive, and scalable manufacturing of nano/micro/macro-fibers. With this technique, virgin and composite fibers may be made in different designs using a wide range of polymers (both natural and synthetic). Electrospun protein fibers (EPF) shave desirable capabilities such as biocompatibility, low toxicity, degradability, and solvolysis. However, issues with the proteins' processibility have limited their widespread utilization. This paper gives an overview of the features of protein-based biomaterials, which are already being employed and has the potential to be exploited for ES. State-of-the-art examples showcasing the usefulness of EPFs in the food and biomedical industries, including tissue engineering, wound dressings, and drug delivery, provided in the applications. The EPFs' future perspective and the challenge they pose are presented at the end. It is believed that protein and biopolymeric nanofibers will soon be manufactured on an industrial scale owing to the limitations of employing synthetic materials, as well as enormous potential of nanofibers in other fields, such as active food packaging, regenerative medicine, drug delivery, cosmetic, and filtration.
Collapse
|
3
|
Webb BCW, Glogauer M, Santerre JP. The Structure and Function of Next-Generation Gingival Graft Substitutes-A Perspective on Multilayer Electrospun Constructs with Consideration of Vascularization. Int J Mol Sci 2022; 23:ijms23095256. [PMID: 35563649 PMCID: PMC9099797 DOI: 10.3390/ijms23095256] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/09/2022] [Revised: 05/05/2022] [Accepted: 05/06/2022] [Indexed: 12/10/2022] Open
Abstract
There is a shortage of suitable tissue-engineered solutions for gingival recession, a soft tissue defect of the oral cavity. Autologous tissue grafts lead to an increase in morbidity due to complications at the donor site. Although material substitutes are available on the market, their development is early, and work to produce more functional material substitutes is underway. The latter materials along with newly conceived tissue-engineered substitutes must maintain volumetric form over time and have advantageous mechanical and biological characteristics facilitating the regeneration of functional gingival tissue. This review conveys a comprehensive and timely perspective to provide insight towards future work in the field, by linking the structure (specifically multilayered systems) and function of electrospun material-based approaches for gingival tissue engineering and regeneration. Electrospun material composites are reviewed alongside existing commercial material substitutes’, looking at current advantages and disadvantages. The importance of implementing physiologically relevant degradation profiles and mechanical properties into the design of material substitutes is presented and discussed. Further, given that the broader tissue engineering field has moved towards the use of pre-seeded scaffolds, a review of promising cell options, for generating tissue-engineered autologous gingival grafts from electrospun scaffolds is presented and their potential utility and limitations are discussed.
Collapse
Affiliation(s)
- Brian C. W. Webb
- Faculty of Dentistry, University of Toronto, 124 Edward St, Toronto, ON M5G 1G6, Canada; (B.C.W.W.); (M.G.)
- Institute of Biomedical Engineering, University of Toronto, 164 Collage St Room 407, Toronto, ON M5S 3G9, Canada
| | - Michael Glogauer
- Faculty of Dentistry, University of Toronto, 124 Edward St, Toronto, ON M5G 1G6, Canada; (B.C.W.W.); (M.G.)
| | - J. Paul Santerre
- Faculty of Dentistry, University of Toronto, 124 Edward St, Toronto, ON M5G 1G6, Canada; (B.C.W.W.); (M.G.)
- Institute of Biomedical Engineering, University of Toronto, 164 Collage St Room 407, Toronto, ON M5S 3G9, Canada
- Correspondence:
| |
Collapse
|
4
|
Zhang B, Huang J, Narayan RJ. Gradient scaffolds for osteochondral tissue engineering and regeneration. J Mater Chem B 2021; 8:8149-8170. [PMID: 32776030 DOI: 10.1039/d0tb00688b] [Citation(s) in RCA: 66] [Impact Index Per Article: 22.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/17/2022]
Abstract
The tissue engineering approach for repairing osteochondral (OC) defects involves the fabrication of a biological tissue scaffold that mimics the physiological properties of natural OC tissue (e.g., the gradient transition between the cartilage surface and the subchondral bone). The OC tissue scaffolds described in many research studies exhibit a discrete gradient (e.g., a biphasic or tri/multiphasic structure) or a continuous gradient to mimic OC tissue attributes such as biochemical composition, structure, and mechanical properties. One advantage of a continuous gradient scaffold over biphasic or tri/multiphasic tissue scaffolds is that it more closely mimics natural OC tissue since there is no distinct interface between each layer. Although research studies to this point have yielded good results related to OC regeneration with tissue scaffolds, differences between engineered scaffolds and natural OC tissue remain; due to these differences, current clinical therapies to repair OC defects with engineered scaffolds have not been successful. This paper provides an overview of both discrete and continuous gradient OC tissue scaffolds in terms of cell type, scaffold material, microscale structure, mechanical properties, fabrication methods, and scaffold stimuli. Fabrication of gradient scaffolds with three-dimensional (3D) printing is given special emphasis due to its ability to accurately control scaffold pore geometry. Moreover, the application of computational modeling in OC tissue engineering is considered; for example, efforts to optimize the scaffold structure, mechanical properties, and physical stimuli generated within the scaffold-bioreactor system to predict tissue regeneration are considered. Finally, challenges associated with the repair of OC defects and recommendations for future directions in OC tissue regeneration are proposed.
Collapse
Affiliation(s)
- Bin Zhang
- Department of Mechanical Engineering, University College London, London, UK.
| | - Jie Huang
- Department of Mechanical Engineering, University College London, London, UK.
| | - Roger J Narayan
- Joint Department of Biomedical Engineering, University of North Carolina and North Carolina State University, Raleigh, North Carolina, USA.
| |
Collapse
|
5
|
Nilasaroya A, Kop AM, Morrison DA. Heparin-functionalized hydrogels as growth factor-signaling substrates. J Biomed Mater Res A 2020; 109:374-384. [PMID: 32515102 DOI: 10.1002/jbm.a.37030] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/15/2020] [Revised: 04/29/2020] [Accepted: 05/07/2020] [Indexed: 01/08/2023]
Abstract
Tuneable, bioactive hydrogels present an attractive option as cell-instructive substrates for tissue regeneration. Properties mimicking the extracellular matrix at the site of injury are sought after, in particular the ability to regulate growth factors that are key to the regeneration process. This study demonstrates the successful formation of hydrogels with heparin functionalities and fibroblast growth factor-2 (FGF-2). Poly(2-hydroxyethyl methacrylate)-heparin hydrogels were capable of retaining FGF-2 by specific binding to heparin and subsequently showed sustained presentation of the growth factor to mesenchymal stromal cells (MSC). Heparin acted as stable anchoring molecules for FGF-2 on the substrate and the synergistic effect of the ensuing heparin-FGF-2 complex was evident in supporting long term cell growth. The presence of heparin during 3D scaffold formation was also found to introduce surface roughness and microporosity to the resulting hydrogels. While FGF-2 has been known to encourage MSC growth and maintain their multilineage potential, other heparin-binding ligands such as bone morphogenetic proteins are potent differentiation stimuli for MSC. Therefore preserving MSC multipotency or a push toward a differentiation pathway may be pursued by the choice of ligand applied to and bound by the heparin functionalities on the current substrate.
Collapse
Affiliation(s)
- Anastasia Nilasaroya
- Department of Medical Engineering and Physics, Royal Perth Hospital, Perth, Western Australia, Australia
| | - Alan Matthew Kop
- Department of Medical Engineering and Physics, Royal Perth Hospital, Perth, Western Australia, Australia
| | - David Anthony Morrison
- Department of Medical Engineering and Physics, Royal Perth Hospital, Perth, Western Australia, Australia
| |
Collapse
|
6
|
Lin W, Chen M, Qu T, Li J, Man Y. Three‐dimensional electrospun nanofibrous scaffolds for bone tissue engineering. J Biomed Mater Res B Appl Biomater 2020; 108:1311-1321. [PMID: 31436374 DOI: 10.1002/jbm.b.34479] [Citation(s) in RCA: 58] [Impact Index Per Article: 14.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/18/2019] [Revised: 07/13/2019] [Accepted: 08/06/2019] [Indexed: 02/05/2023]
Affiliation(s)
- Weimin Lin
- State Key Laboratory of Oral Diseases & National Clinical Research Center for Oral Diseases, West China Hospital of StomatologySichuan University Chengdu China
- Department of Oral Implantology, West China Hospital of StomatologySichuan University Chengdu China
| | - Miao Chen
- State Key Laboratory of Oral Diseases & National Clinical Research Center for Oral Diseases, West China Hospital of StomatologySichuan University Chengdu China
| | - Tao Qu
- State Key Laboratory of Oral Diseases & National Clinical Research Center for Oral Diseases, West China Hospital of StomatologySichuan University Chengdu China
| | - Jidong Li
- Research Center for Nano‐Biomaterials, Analytical and Testing CenterSichuan University Chengdu China
| | - Yi Man
- State Key Laboratory of Oral Diseases & National Clinical Research Center for Oral Diseases, West China Hospital of StomatologySichuan University Chengdu China
- Department of Oral Implantology, West China Hospital of StomatologySichuan University Chengdu China
| |
Collapse
|
7
|
Tahmasebi E. Adsorption efficiency enhancing of electrospun polycaprolactone nanofibers towards acidic polar drugs through the incorporation of a composite of graphene oxide nanosheets and Al 30 polyoxocations: a comparative study. Analyst 2018; 143:4684-4698. [PMID: 30179241 DOI: 10.1039/c8an01066h] [Citation(s) in RCA: 13] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/18/2022]
Abstract
The main objective of this study focuses on exploration of the feasibility of Al30 polyoxocations for preparation of a novel sorbent material for a solid-phase extraction (SPE) method by selective adsorption and extraction of a class of compounds considering the type of interactions involved in the adsorption process. Accordingly, first Al30 polyoxocations were synthesized and their composite was prepared with graphene oxide (GO) nanosheets as a suitable substrate to be introduced as a SPE sorbent material. Then, the prepared composite was incorporated into polycaprolactone (PCL) nanofibers via electrospinning to present an alternative sorbent for SPE-based on a GO/Al30 nanocomposite (GO/Al30 NC) creating no need for filtering or centrifuging steps. Intercalation of Al30 polyoxocations into the GO layers and the incorporation of GO/Al30 NC into PCL nanofibers was successfully confirmed through FE-SEM, TEM, EDX, XRD, BET, TGA, IR spectroscopy, and zeta potential determination. For investigating the types of probable interactions involved in the adsorption process of different compounds on the proposed sorbents, four statin drugs, cholesterol-lowering agents with various polarity and ionization properties, were selected as model analytes. Factors affecting the extraction efficiency of dispersive SPE and immersed SPE methods using GO/Al30 NC and GO/Al30 NC-PCL nanofibers, respectively, were investigated and optimized. Under optimal conditions, acceptable analytical figures of merit were obtained for both SPE methods. A comparison of extraction efficiencies of the target drugs by the two proposed sorbents, as well as GO nanosheets and PCL nanofibers, was accomplished to study the types of interactions as well as the adsorption mechanism. The results revealed that GO/Al30 NC, having many polar and anion exchange sites caused by Al30 polyoxocations, is a good selective sorbent for acidic polar compounds which their extraction by nonpolar sorbents is not desirable. Additionally, GO/Al30 NC-PCL nanofibers exhibited extraction capability for a wide range of compounds from acidic polar to nonpolar and nonionizable ones.
Collapse
Affiliation(s)
- Elham Tahmasebi
- Department of Chemistry, Institute for Advanced Studies in Basic Sciences (IASBS), P.O. Box 45195-1159, Zanjan, Iran.
| |
Collapse
|
8
|
Williams A, Nowak JF, Dass R, Samuel J, Mills KL. Toward Morphologically Relevant Extracellular Matrix in Vitro Models: 3D Fiber Reinforced Hydrogels. Front Physiol 2018; 9:966. [PMID: 30087619 PMCID: PMC6066552 DOI: 10.3389/fphys.2018.00966] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/06/2018] [Accepted: 07/02/2018] [Indexed: 11/16/2022] Open
Abstract
The extracellular matrix (ECM) is known to play an important role in the health of cells and tissues. Not only are chemical signals transmitted via bonds and tightly controlled diffusion, but the structure of the ECM also provides important physical signaling for the cells attached to it. The structure is composed of a mesh of fibrous proteins, such as collagen, embedded in a hydrated gel matrix of glycosaminoglycans. To study cell behavior with respect to the combined morphology and mechanics of such matrices is not currently possible with the types of 3D cell culture matrices available. Most of the cell culture matrices are single-phase bio- or polymeric hydrogels. Therefore, here we developed a continuous hybrid manufacturing process to make fiber-reinforced composite hydrogels. A far field electrospinning process was used to deposit the fibrous component with the aid of guiding electrodes; and a gravity-assisted, droplet-based system controlled the rate of addition of the cell-laden hydrogel component. The addition of the fibrous component slightly increased the elastic modulus of the pure hydrogel. The cells that were embedded into the fiber-reinforced hydrogels were viable for 8 days. The cells were randomly placed in the matrix such that some had no contact to the fibers and others were initially in proximity to fibers. The cells with no contact to fibers grew into spheroidal clusters within the hydrogel, and those in proximity to the fibers spread out and grew along the fibers showing that the fiber-reinforced hydrogels are able to control cell behavior with morphological cues.
Collapse
Affiliation(s)
- Ashok Williams
- Department of Mechanical, Aerospace, Nuclear Engineering, Rensselaer Polytechnic Institute, Troy, NY, United States.,Center for Biotechnology and Interdisciplinary Studies, Rensselaer Polytechnic Institute, Troy, NY, United States
| | - James F Nowak
- Department of Mechanical, Aerospace, Nuclear Engineering, Rensselaer Polytechnic Institute, Troy, NY, United States
| | - Rachel Dass
- Department of Mechanical, Aerospace, Nuclear Engineering, Rensselaer Polytechnic Institute, Troy, NY, United States.,Center for Biotechnology and Interdisciplinary Studies, Rensselaer Polytechnic Institute, Troy, NY, United States
| | - Johnson Samuel
- Department of Mechanical, Aerospace, Nuclear Engineering, Rensselaer Polytechnic Institute, Troy, NY, United States
| | - K L Mills
- Department of Mechanical, Aerospace, Nuclear Engineering, Rensselaer Polytechnic Institute, Troy, NY, United States.,Center for Biotechnology and Interdisciplinary Studies, Rensselaer Polytechnic Institute, Troy, NY, United States
| |
Collapse
|
9
|
Stocco TD, Bassous NJ, Zhao S, Granato AEC, Webster TJ, Lobo AO. Nanofibrous scaffolds for biomedical applications. NANOSCALE 2018; 10:12228-12255. [PMID: 29947408 DOI: 10.1039/c8nr02002g] [Citation(s) in RCA: 40] [Impact Index Per Article: 6.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/08/2023]
Abstract
Tissue engineering is an emergent and very interesting research field, providing potential solutions for a myriad of challenges in healthcare. Fibrous scaffolds specifically have shown promise as an effective tissue engineering method, as their high length-to-width ratio mimics that of extracellular matrix components, which in turn guides tissue formation, promotes cellular adhesion and improves mechanical properties. In this review paper, we discuss in detail both the importance of fibrous scaffolds for the promotion of tissue growth and the different methods to produce fibrous biomaterials to possess favorable and unique characteristics. Here, we focus on the pressing need to develop biomimetic structures that promote an ideal environment to encourage tissue formation. In addition, we discuss different biomedical applications in which fibrous scaffolds can be useful, identifying their importance, relevant aspects, and remaining significant challenges. In conclusion, we provide comments on the future direction of fibrous scaffolds and the best way to produce them, proposed in light of recent technological advances and the newest and most promising fabrication techniques.
Collapse
Affiliation(s)
- Thiago D Stocco
- Faculdade de Ciências Médicas, Universidade Estadual de Campinas, Campinas, São Paulo, Brazil
| | | | | | | | | | | |
Collapse
|
10
|
Tuin SA, Pourdeyhimi B, Loboa EG. Fabrication of novel high surface area mushroom gilled fibers and their effects on human adipose derived stem cells under pulsatile fluid flow for tissue engineering applications. Acta Biomater 2016; 36:220-30. [PMID: 26992369 DOI: 10.1016/j.actbio.2016.03.025] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/02/2015] [Revised: 02/08/2016] [Accepted: 03/14/2016] [Indexed: 01/20/2023]
Abstract
UNLABELLED The fabrication and characterization of novel high surface area hollow gilled fiber tissue engineering scaffolds via industrially relevant, scalable, repeatable, high speed, and economical nonwoven carding technology is described. Scaffolds were validated as tissue engineering scaffolds using human adipose derived stem cells (hASC) exposed to pulsatile fluid flow (PFF). The effects of fiber morphology on the proliferation and viability of hASC, as well as effects of varied magnitudes of shear stress applied via PFF on the expression of the early osteogenic gene marker runt related transcription factor 2 (RUNX2) were evaluated. Gilled fiber scaffolds led to a significant increase in proliferation of hASC after seven days in static culture, and exhibited fewer dead cells compared to pure PLA round fiber controls. Further, hASC-seeded scaffolds exposed to 3 and 6dyn/cm(2) resulted in significantly increased mRNA expression of RUNX2 after one hour of PFF in the absence of soluble osteogenic induction factors. This is the first study to describe a method for the fabrication of high surface area gilled fibers and scaffolds. The scalable manufacturing process and potential fabrication across multiple nonwoven and woven platforms makes them promising candidates for a variety of applications that require high surface area fibrous materials. STATEMENT OF SIGNIFICANCE We report here for the first time the successful fabrication of novel high surface area gilled fiber scaffolds for tissue engineering applications. Gilled fibers led to a significant increase in proliferation of human adipose derived stem cells after one week in culture, and a greater number of viable cells compared to round fiber controls. Further, in the absence of osteogenic induction factors, gilled fibers led to significantly increased mRNA expression of an early marker for osteogenesis after exposure to pulsatile fluid flow. This is the first study to describe gilled fiber fabrication and their potential for tissue engineering applications. The repeatable, industrially scalable, and versatile fabrication process makes them promising candidates for a variety of scaffold-based tissue engineering applications.
Collapse
|
11
|
Leferink AM, van Blitterswijk CA, Moroni L. Methods of Monitoring Cell Fate and Tissue Growth in Three-Dimensional Scaffold-Based Strategies for In Vitro Tissue Engineering. TISSUE ENGINEERING PART B-REVIEWS 2016; 22:265-83. [PMID: 26825610 DOI: 10.1089/ten.teb.2015.0340] [Citation(s) in RCA: 15] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 12/12/2022]
Abstract
In the field of tissue engineering, there is a need for methods that allow assessing the performance of tissue-engineered constructs noninvasively in vitro and in vivo. To date, histological analysis is the golden standard to retrieve information on tissue growth, cellular distribution, and cell fate on tissue-engineered constructs after in vitro cell culture or on explanted specimens after in vivo applications. Yet, many advances have been made to optimize imaging techniques for monitoring tissue-engineered constructs with a sub-mm or μm resolution. Many imaging modalities have first been developed for clinical applications, in which a high penetration depth has been often more important than lateral resolution. In this study, we have reviewed the current state of the art in several imaging approaches that have shown to be promising in monitoring cell fate and tissue growth upon in vitro culture. Depending on the aimed tissue type and scaffold properties, some imaging methods are more applicable than others. Optical methods are mostly suited for transparent materials such as hydrogels, whereas magnetic resonance-based methods are mostly applied to obtain contrast between hard and soft tissues regardless of their transparency. Overall, this review shows that the field of imaging in scaffold-based tissue engineering is developing at a fast pace and has the potential to overcome the limitations of destructive endpoint analysis.
Collapse
Affiliation(s)
- Anne M Leferink
- 1 Department of Tissue Regeneration, MIRA Institute, University of Twente , Enschede, The Netherlands .,2 Department of Complex Tissue Regeneration, Maastricht University , Maastricht, The Netherlands .,3 BIOS/Lab-on-a-chip Group, MIRA Institute, University of Twente , Enschede, The Netherlands
| | - Clemens A van Blitterswijk
- 1 Department of Tissue Regeneration, MIRA Institute, University of Twente , Enschede, The Netherlands .,2 Department of Complex Tissue Regeneration, Maastricht University , Maastricht, The Netherlands
| | - Lorenzo Moroni
- 1 Department of Tissue Regeneration, MIRA Institute, University of Twente , Enschede, The Netherlands .,2 Department of Complex Tissue Regeneration, Maastricht University , Maastricht, The Netherlands
| |
Collapse
|
12
|
Tuin SA, Pourdeyhimi B, Loboa EG. Creating tissues from textiles: scalable nonwoven manufacturing techniques for fabrication of tissue engineering scaffolds. ACTA ACUST UNITED AC 2016; 11:015017. [PMID: 26908485 DOI: 10.1088/1748-6041/11/1/015017] [Citation(s) in RCA: 26] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/12/2022]
Abstract
Electrospun nonwovens have been used extensively for tissue engineering applications due to their inherent similarities with respect to fibre size and morphology to that of native extracellular matrix (ECM). However, fabrication of large scaffold constructs is time consuming, may require harsh organic solvents, and often results in mechanical properties inferior to the tissue being treated. In order to translate nonwoven based tissue engineering scaffold strategies to clinical use, a high throughput, repeatable, scalable, and economic manufacturing process is needed. We suggest that nonwoven industry standard high throughput manufacturing techniques (meltblowing, spunbond, and carding) can meet this need. In this study, meltblown, spunbond and carded poly(lactic acid) (PLA) nonwovens were evaluated as tissue engineering scaffolds using human adipose derived stem cells (hASC) and compared to electrospun nonwovens. Scaffolds were seeded with hASC and viability, proliferation, and differentiation were evaluated over the course of 3 weeks. We found that nonwovens manufactured via these industry standard, commercially relevant manufacturing techniques were capable of supporting hASC attachment, proliferation, and both adipogenic and osteogenic differentiation of hASC, making them promising candidates for commercialization and translation of nonwoven scaffold based tissue engineering strategies.
Collapse
Affiliation(s)
- S A Tuin
- Joint Department of Biomedical Engineering, University of North Carolina at Chapel Hill and North Carolina State University, 4208 EB3, Campus Box 7115, Raleigh, NC 27695, USA
| | | | | |
Collapse
|
13
|
Fabrication of functional PLGA-based electrospun scaffolds and their applications in biomedical engineering. MATERIALS SCIENCE & ENGINEERING. C, MATERIALS FOR BIOLOGICAL APPLICATIONS 2016; 59:1181-1194. [DOI: 10.1016/j.msec.2015.11.026] [Citation(s) in RCA: 137] [Impact Index Per Article: 17.1] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Received: 07/01/2015] [Revised: 10/22/2015] [Accepted: 11/09/2015] [Indexed: 12/17/2022]
|
14
|
Mohiti-Asli M, Saha S, Murphy SV, Gracz H, Pourdeyhimi B, Atala A, Loboa EG. Ibuprofen loaded PLA nanofibrous scaffolds increase proliferation of human skin cells in vitro and promote healing of full thickness incision wounds in vivo. J Biomed Mater Res B Appl Biomater 2015; 105:327-339. [PMID: 26509902 DOI: 10.1002/jbm.b.33520] [Citation(s) in RCA: 43] [Impact Index Per Article: 4.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/02/2015] [Revised: 07/03/2015] [Accepted: 07/18/2015] [Indexed: 12/18/2022]
Abstract
This article presents successful incorporation of ibuprofen in polylactic acid (PLA) nanofibers to create scaffolds for the treatment of both acute and chronic wounds. Nanofibrous PLA scaffolds containing 10, 20, or 30 wt % ibuprofen were created and ibuprofen release profiles quantified. In vitro cytotoxicity to human epidermal keratinocytes (HEK) and human dermal fibroblasts (HDF) of the three scaffolds with varying ibuprofen concentrations were evaluated and compared to pure PLA nanofibrous scaffolds. Thereafter, scaffolds loaded with ibuprofen at the concentration that promoted human skin cell viability and proliferation (20 wt %) were evaluated in vivo in nude mice using a full thickness skin incision model to determine the ability of these scaffolds to promote skin regeneration and/or assist with scarless healing. Both acellular and HEK and HDF cell-seeded 20 wt % ibuprofen loaded nanofibrous bandages reduced wound contraction compared with wounds treated with Tegaderm™ and sterile gauze. Newly regenerated skin on wounds treated with cell-seeded 20 wt % ibuprofen bandages exhibited significantly greater blood vessel formation relative to acellular ibuprofen bandages. We have found that degradable anti-inflammatory scaffolds containing 20 wt % ibuprofen promote human skin cell viability and proliferation in vitro, reduce wound contraction in vivo, and when seeded with skin cells, also enhance new blood vessel formation. The approaches and results reported here hold promise for multiple skin tissue engineering and wound healing applications. © 2015 Wiley Periodicals, Inc. J Biomed Mater Res Part B: Appl Biomater, 105B: 327-339, 2017.
Collapse
Affiliation(s)
- M Mohiti-Asli
- Joint Department of Biomedical Engineering at University of North Carolina at Chapel Hill, North Carolina State University, Raleigh, North Carolina, 27695
| | - S Saha
- Joint Department of Biomedical Engineering at University of North Carolina at Chapel Hill, North Carolina State University, Raleigh, North Carolina, 27695
| | - S V Murphy
- Wake Forest Institute for Regenerative Medicine, Wake Forest University School of Medicine, Winston-Salem, North Carolina, 27157
| | - H Gracz
- Department of Molecular and Structural Biochemistry, North Carolina State University, Raleigh, North Carolina, 27695
| | - B Pourdeyhimi
- College of Textiles at North Carolina State University, Raleigh, North Carolina, 27695
| | - A Atala
- Wake Forest Institute for Regenerative Medicine, Wake Forest University School of Medicine, Winston-Salem, North Carolina, 27157
| | - E G Loboa
- Joint Department of Biomedical Engineering at University of North Carolina at Chapel Hill, North Carolina State University, Raleigh, North Carolina, 27695.,Department of Materials Science and Engineering, North Carolina State University, Raleigh, North Carolina, 27695
| |
Collapse
|
15
|
Orr SB, Chainani A, Hippensteel KJ, Kishan A, Gilchrist C, Garrigues NW, Ruch DS, Guilak F, Little D. Aligned multilayered electrospun scaffolds for rotator cuff tendon tissue engineering. Acta Biomater 2015; 24:117-26. [PMID: 26079676 PMCID: PMC4560626 DOI: 10.1016/j.actbio.2015.06.010] [Citation(s) in RCA: 127] [Impact Index Per Article: 14.1] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/29/2015] [Revised: 05/13/2015] [Accepted: 06/09/2015] [Indexed: 12/29/2022]
Abstract
The rotator cuff consists of several tendons and muscles that provide stability and force transmission in the shoulder joint. Whereas most rotator cuff tears are amenable to suture repair, the overall success rate of repair is low, and massive tears are prone to re-tear. Extracellular matrix (ECM) patches are used to augment suture repair, but they have limitations. Tissue-engineered approaches provide a promising solution for massive rotator cuff tears. Previous studies have shown that, compared to nonaligned scaffolds, aligned electrospun polymer scaffolds exhibit greater anisotropy and exert a greater tenogenic effect. Nevertheless, achieving rapid cell infiltration through the full thickness of the scaffold is challenging, and scaling to a translationally relevant size may be difficult. Our goal was to evaluate whether a novel method of alignment, combining a multilayered electrospinning technique with a hybrid of several electrospinning alignment techniques, would permit cell infiltration and collagen deposition through the thickness of poly(ε-caprolactone) scaffolds following seeding with human adipose-derived stem cells. Furthermore, we evaluated whether multilayered aligned scaffolds enhanced collagen alignment, tendon-related gene expression, and mechanical properties compared to multilayered nonaligned scaffolds. Both aligned and nonaligned multilayered scaffolds demonstrated cell infiltration and ECM deposition through the full thickness of the scaffold after only 28days of culture. Aligned scaffolds displayed significantly increased expression of tenomodulin compared to nonaligned scaffolds and exhibited aligned collagen fibrils throughout the full thickness, the presence of which may account for the increased yield stress and Young's modulus of cell-seeded aligned scaffolds along the axis of fiber alignment. STATEMENT OF SIGNIFICANCE Rotator cuff tears are an important clinical problem in the shoulder, with over 300,000 surgical repairs performed annually. Re-tear rates may be high, and current methods used to augment surgical repair have limited evidence to support their clinical use due to inadequate initial mechanical properties and slow cellular infiltration. Tissue engineering approaches such as electrospinning have shown similar challenges in previous studies. In this study, a novel technique to align electrospun fibers while using a multilayered approach demonstrated increased mechanical properties and development of aligned collagen through the full thickness of the scaffolds compared to nonaligned multilayered scaffolds, and both types of scaffolds demonstrated rapid cell infiltration through the full thickness of the scaffold.
Collapse
Affiliation(s)
- Steven B Orr
- Department of Orthopaedic Surgery, Duke University Medical Center, Durham, NC 27710, USA
| | - Abby Chainani
- Department of Orthopaedic Surgery, Duke University Medical Center, Durham, NC 27710, USA; Department of Biomedical Engineering, Duke University, Durham, NC 27708, USA
| | - Kirk J Hippensteel
- Department of Orthopaedic Surgery, Duke University Medical Center, Durham, NC 27710, USA
| | - Alysha Kishan
- Department of Orthopaedic Surgery, Duke University Medical Center, Durham, NC 27710, USA; Department of Biomedical Engineering, Duke University, Durham, NC 27708, USA
| | - Christopher Gilchrist
- Department of Orthopaedic Surgery, Duke University Medical Center, Durham, NC 27710, USA
| | - N William Garrigues
- Department of Orthopaedic Surgery, Duke University Medical Center, Durham, NC 27710, USA; Department of Biomedical Engineering, Duke University, Durham, NC 27708, USA
| | - David S Ruch
- Department of Orthopaedic Surgery, Duke University Medical Center, Durham, NC 27710, USA
| | - Farshid Guilak
- Department of Orthopaedic Surgery, Duke University Medical Center, Durham, NC 27710, USA; Department of Biomedical Engineering, Duke University, Durham, NC 27708, USA
| | - Dianne Little
- Department of Orthopaedic Surgery, Duke University Medical Center, Durham, NC 27710, USA.
| |
Collapse
|
16
|
Brennan MÁ, Renaud A, Gamblin AL, D'Arros C, Nedellec S, Trichet V, Layrolle P. 3D cell culture and osteogenic differentiation of human bone marrow stromal cells plated onto jet-sprayed or electrospun micro-fiber scaffolds. ACTA ACUST UNITED AC 2015; 10:045019. [PMID: 26238732 DOI: 10.1088/1748-6041/10/4/045019] [Citation(s) in RCA: 41] [Impact Index Per Article: 4.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/11/2022]
Abstract
A major limitation of the 2D culture systems is that they fail to recapitulate the in vivo 3D cellular microenvironment whereby cell-cell and cell-extracellular matrix (ECM) interactions occur. In this paper, a biomaterial scaffold that mimics the structure of collagen fibers was produced by jet-spraying. This micro-fiber polycaprolactone (PCL) scaffold was evaluated for 3D culture of human bone marrow mesenchymal stromal cells (MSCs) in comparison with a commercially available electrospun scaffold. The jet-sprayed scaffolds had larger pore diameters, greater porosity, smaller diameter fibers, and more heterogeneous fiber diameter size distribution compared to the electrospun scaffolds. Cells on jet-sprayed constructs exhibited spread morphology with abundant cytoskeleton staining, whereas MSCs on electrospun scaffolds appeared less extended with fewer actin filaments. MSC proliferation and cell infiltration occurred at a faster rate on jet-sprayed compared to electrospun scaffolds. Osteogenic differentiation of MSCs and ECM production as measured by ALP, collagen and calcium deposition was superior on jet-sprayed compared to electrospun scaffolds. The jet-sprayed scaffold which mimics the native ECM and permits homogeneous cell infiltration is important for 3D in vitro applications such as bone cellular interaction studies or drug testing, as well as bone tissue engineering strategies.
Collapse
Affiliation(s)
- Meadhbh Á Brennan
- INSERM UMR 957, Laboratory of Pathophysiology of Bone Resorption and Primary Bone Tumour Therapy, Faculty of Medicine, University of Nantes, France
| | | | | | | | | | | | | |
Collapse
|
17
|
Mellor LF, Mohiti-Asli M, Williams J, Kannan A, Dent MR, Guilak F, Loboa EG. Extracellular Calcium Modulates Chondrogenic and Osteogenic Differentiation of Human Adipose-Derived Stem Cells: A Novel Approach for Osteochondral Tissue Engineering Using a Single Stem Cell Source. Tissue Eng Part A 2015; 21:2323-33. [PMID: 26035347 DOI: 10.1089/ten.tea.2014.0572] [Citation(s) in RCA: 62] [Impact Index Per Article: 6.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/26/2023] Open
Abstract
We have previously shown that elevating extracellular calcium from a concentration of 1.8 to 8 mM accelerates and increases human adipose-derived stem cell (hASC) osteogenic differentiation and cell-mediated calcium accretion, even in the absence of any other soluble osteogenic factors in the culture medium. However, the effects of elevated calcium on hASC chondrogenic differentiation have not been reported. The goal of this study was to determine the effects of varied calcium concentrations on chondrogenic differentiation of hASC. We hypothesized that exposure to elevated extracellular calcium (8 mM concentration) in a chondrogenic differentiation medium (CDM) would inhibit chondrogenesis of hASC when compared to basal calcium (1.8 mM concentration) controls. We further hypothesized that a full osteochondral construct could be engineered by controlling local release of calcium to induce site-specific chondrogenesis and osteogenesis using only hASC as the cell source. Human ASC was cultured as micromass pellets in CDM containing transforming growth factor-β1 and bone morphogenetic protein 6 for 28 days at extracellular calcium concentrations of either 1.8 mM (basal) or 8 mM (elevated). Our findings indicated that elevated calcium induced osteogenesis and inhibited chondrogenesis in hASC. Based on these findings, stacked polylactic acid nanofibrous scaffolds containing either 0% or 20% tricalcium phosphate (TCP) nanoparticles were electrospun and tested for site-specific chondrogenesis and osteogenesis. Histological assays confirmed that human ASC differentiated locally to generate calcified tissue in layers containing 20% TCP, and cartilage in the layers with no TCP when cultured in CDM. This is the first study to report the effects of elevated calcium on chondrogenic differentiation of hASC, and to develop osteochondral nanofibrous scaffolds using a single cell source and controlled calcium release to induce site-specific differentiation. This approach holds great promise for osteochondral tissue engineering using a single cell source (hASC) and single scaffold.
Collapse
Affiliation(s)
- Liliana F Mellor
- 1 Joint Department of Biomedical Engineering at University of North Carolina at Chapel Hill, North Carolina State University , Raleigh, North Carolina
| | - Mahsa Mohiti-Asli
- 1 Joint Department of Biomedical Engineering at University of North Carolina at Chapel Hill, North Carolina State University , Raleigh, North Carolina
| | - John Williams
- 1 Joint Department of Biomedical Engineering at University of North Carolina at Chapel Hill, North Carolina State University , Raleigh, North Carolina
| | - Arthi Kannan
- 1 Joint Department of Biomedical Engineering at University of North Carolina at Chapel Hill, North Carolina State University , Raleigh, North Carolina
| | - Morgan R Dent
- 1 Joint Department of Biomedical Engineering at University of North Carolina at Chapel Hill, North Carolina State University , Raleigh, North Carolina
| | - Farshid Guilak
- 2 Departments of Orthopedic Surgery and Biomedical Engineering, Duke University Medical Center , Durham, North Carolina
| | - Elizabeth G Loboa
- 1 Joint Department of Biomedical Engineering at University of North Carolina at Chapel Hill, North Carolina State University , Raleigh, North Carolina.,3 Department of Materials Science and Engineering, North Carolina State University , Raleigh, North Carolina
| |
Collapse
|
18
|
Huang J, Deng H, Song D, Xu H. Electrospun polystyrene/graphene nanofiber film as a novel adsorbent of thin film microextraction for extraction of aldehydes in human exhaled breath condensates. Anal Chim Acta 2015; 878:102-8. [DOI: 10.1016/j.aca.2015.03.053] [Citation(s) in RCA: 66] [Impact Index Per Article: 7.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/06/2015] [Revised: 03/29/2015] [Accepted: 03/31/2015] [Indexed: 10/23/2022]
|
19
|
Huang SH, Lin YN, Lee SS, Chai CY, Chang HW, Lin TM, Lai CS, Lin SD. New adipose tissue formation by human adipose-derived stem cells with hyaluronic acid gel in immunodeficient mice. Int J Med Sci 2015; 12:154-62. [PMID: 25589892 PMCID: PMC4293181 DOI: 10.7150/ijms.9964] [Citation(s) in RCA: 21] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 06/23/2014] [Accepted: 12/30/2014] [Indexed: 11/05/2022] Open
Abstract
BACKGROUND Currently available injectable fillers have demonstrated limited durability. This report proposes the in vitro culture of human adipose-derived stem cells (hASCs) on hyaluronic acid (HA) gel for in vivo growth of de novo adipose tissue. METHODS For in vitro studies, hASCs were isolated from human adipose tissue and were confirmed by multi-lineage differentiation and flow cytometry. hASCs were cultured on HA gel. The effectiveness of cell attachment and proliferation on HA gel was surveyed by inverted light microscopy. For in vivo studies, HA gel containing hASCs, hASCs without HA gel, HA gel alone were allocated and subcutaneously injected into the subcutaneous pocket in the back of nude mice (n=6) in each group. At eight weeks post-injection, the implants were harvested for histological examination by hematoxylin and eosin (H&E) stain, Oil-Red O stain and immunohistochemical staining. The human-specific Alu gene was examined. RESULTS hASCs were well attachment and proliferation on the HA gel. In vivo grafts showed well-organized new adipose tissue on the HA gel by histologic examination and Oil-Red O stain. Analysis of neo-adipose tissues by PCR revealed the presence of the Alu gene. This study demonstrated not only the successful culture of hASCs on HA gel, but also their full proliferation and differentiation into adipose tissue. CONCLUSIONS The efficacy of injected filler could be permanent since the reduction of the volume of the HA gel after bioabsorption could be replaced by new adipose tissue generated by hASCs. This is a promising approach for developing long lasting soft tissue filler.
Collapse
Affiliation(s)
- Shu-Hung Huang
- 1. Graduate Institute of Medicine, College of Medicine, Kaohsiung Medical University, Kaohsiung, Taiwan ; 2. Center for Stem Cell Research, Kaohsiung Medical University, Kaohsiung, Taiwan ; 3. Division of Plastic Surgery, Department of Surgery, Kaohsiung Medical University Hospital, Kaohsiung Medical University, Kaohsiung, Taiwan ; 4. Department of Surgery, Faculty of Medicine, College of Medicine, Kaohsiung Medical University, Kaohsiung, Taiwan
| | - Yun-Nan Lin
- 3. Division of Plastic Surgery, Department of Surgery, Kaohsiung Medical University Hospital, Kaohsiung Medical University, Kaohsiung, Taiwan
| | - Su-Shin Lee
- 2. Center for Stem Cell Research, Kaohsiung Medical University, Kaohsiung, Taiwan ; 3. Division of Plastic Surgery, Department of Surgery, Kaohsiung Medical University Hospital, Kaohsiung Medical University, Kaohsiung, Taiwan ; 4. Department of Surgery, Faculty of Medicine, College of Medicine, Kaohsiung Medical University, Kaohsiung, Taiwan
| | - Chee-Yin Chai
- 5. Department of Pathology, Kaohsiung Medical University Hospital, Kaohsiung, Taiwan
| | - Hsueh-Wei Chang
- 6. Department of Biomedical Science and Environmental Biology, Kaohsiung Medical University, Kaohsiung, Taiwan
| | - Tsai-Ming Lin
- 3. Division of Plastic Surgery, Department of Surgery, Kaohsiung Medical University Hospital, Kaohsiung Medical University, Kaohsiung, Taiwan
| | - Chung-Sheng Lai
- 2. Center for Stem Cell Research, Kaohsiung Medical University, Kaohsiung, Taiwan ; 3. Division of Plastic Surgery, Department of Surgery, Kaohsiung Medical University Hospital, Kaohsiung Medical University, Kaohsiung, Taiwan ; 4. Department of Surgery, Faculty of Medicine, College of Medicine, Kaohsiung Medical University, Kaohsiung, Taiwan
| | - Sin-Daw Lin
- 2. Center for Stem Cell Research, Kaohsiung Medical University, Kaohsiung, Taiwan ; 3. Division of Plastic Surgery, Department of Surgery, Kaohsiung Medical University Hospital, Kaohsiung Medical University, Kaohsiung, Taiwan ; 4. Department of Surgery, Faculty of Medicine, College of Medicine, Kaohsiung Medical University, Kaohsiung, Taiwan
| |
Collapse
|
20
|
Haslauer CM, Avery MR, Pourdeyhimi B, Loboa EG. Translating textiles to tissue engineering: Creation and evaluation of microporous, biocompatible, degradable scaffolds using industry relevant manufacturing approaches and human adipose derived stem cells. J Biomed Mater Res B Appl Biomater 2014; 103:1050-8. [PMID: 25229198 DOI: 10.1002/jbm.b.33291] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/20/2013] [Revised: 07/13/2014] [Accepted: 09/01/2014] [Indexed: 01/25/2023]
Abstract
Polymeric scaffolds have emerged as a means of generating three-dimensional tissues, such as for the treatment of bone injuries and nonunions. In this study, a fibrous scaffold was designed using the biocompatible, degradable polymer poly-lactic acid in combination with a water dispersible sacrificial polymer, EastONE. Fibers were generated via industry relevant, facile scale-up melt-spinning techniques with an islands-in-the-sea geometry. Following removal of EastONE, a highly porous fiber remained possessing 12 longitudinal channels and pores throughout all internal and external fiber walls. Weight loss and surface area characterization confirmed the generation of highly porous fibers as observed via focused ion beam/scanning electron microscopy. Porous fibers were then knit into a three-dimensional scaffold and seeded with human adipose-derived stem cells (hASC). Confocal microscopy images confirmed hASC attachment to the fiber walls and proliferation throughout the knit structure. Quantification of cell-mediated calcium accretion following culture in osteogenic differentiation medium confirmed hASC differentiation throughout the porous constructs. These results suggest incorporation of a sacrificial polymer within islands-in-the-sea fibers generates a highly porous scaffold capable of supporting stem cell viability and differentiation with the potential to generate large three-dimensional constructs for bone regeneration and/or other tissue engineering applications.
Collapse
Affiliation(s)
- Carla M Haslauer
- Joint Department of Biomedical Engineering, at UNC-Chapel Hill and NC State University, 4208B EBIII, CB 7115, Raleigh, North Carolina, 27695
| | - Matthew R Avery
- NCSU Department of Statistics, 5109 SAS Hall, North Carolina State University, Raleigh, North Carolina, 27695
| | - Behnam Pourdeyhimi
- Textile Engineering, Chemistry and Science, 3427 College of Textiles, North Carolina State University, Raleigh, North Carolina, 27695
| | - Elizabeth G Loboa
- Joint Department of Biomedical Engineering, at UNC-Chapel Hill and NC State University, 4208B EBIII, CB 7115, Raleigh, North Carolina, 27695.,Department of Materials Science and Engineering, North Carolina State University, Raleigh, North Carolina, 27695
| |
Collapse
|
21
|
Ajalloueian F, Zeiai S, Fossum M, Hilborn JG. Constructs of electrospun PLGA, compressed collagen and minced urothelium for minimally manipulated autologous bladder tissue expansion. Biomaterials 2014; 35:5741-8. [DOI: 10.1016/j.biomaterials.2014.04.002] [Citation(s) in RCA: 41] [Impact Index Per Article: 4.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/09/2014] [Accepted: 04/01/2014] [Indexed: 11/25/2022]
|
22
|
Dai X, Huang YC. Electrospun fibrous scaffolds of Poly(glycerol-dodecanedioate) for engineering neural tissues from mouse embryonic stem cells. J Vis Exp 2014. [PMID: 24961272 DOI: 10.3791/51587] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/17/2023] Open
Abstract
For tissue engineering applications, the preparation of biodegradable and biocompatible scaffolds is the most desirable but challenging task. Among the various fabrication methods, electrospinning is the most attractive one due to its simplicity and versatility. Additionally, electrospun nanofibers mimic the size of natural extracellular matrix ensuring additional support for cell survival and growth. This study showed the viability of the fabrication of long fibers spanning a larger deposit area for a novel biodegradable and biocompatible polymer named poly(glycerol-dodecanoate) (PGD)(1) by using a newly designed collector for electrospinning. PGD exhibits unique elastic properties with similar mechanical properties to nerve tissues, thus it is suitable for neural tissue engineering applications. The synthesis and fabrication set-up for making fibrous scaffolding materials was simple, highly reproducible, and inexpensive. In biocompatibility testing, cells derived from mouse embryonic stem cells could adhere to and grow on the electrospun PGD fibers. In summary, this protocol provided a versatile fabrication method for making PGD electrospun fibers to support the growth of mouse embryonic stem cell derived neural lineage cells.
Collapse
Affiliation(s)
- Xizi Dai
- Department of Biomedical Engineering, Florida International University
| | - Yen-Chih Huang
- Department of Biomedical Engineering, Florida International University;
| |
Collapse
|
23
|
Highley CB, Rodell CB, Kim IL, Wade RJ, Burdick J. Ordered, adherent layers of nanofibers enabled by supramolecular interactions. J Mater Chem B 2014; 2:8110-8115. [PMID: 25408916 PMCID: PMC4232958 DOI: 10.1039/c4tb00724g] [Citation(s) in RCA: 16] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/03/2023]
Abstract
Aligned nanofibrous substrates can be created by electrospinning, but methods for creating multilamellar structures of aligned fibers are limited. Here, apposed nanofibrous scaffolds with pendant β-cyclodextrin (CD) were adhered together by adamantane (Ad) modified hyaluronic acid, exploiting the guest-host interactions of CD and Ad for macroscopic assembly. Stable user-defined multi-layered scaffolds were formed for cell culture or tissue engineering.
Collapse
Affiliation(s)
- Christopher B. Highley
- Department of Bioengineering, University of Pennsylvania, 240 Skirkanich Hall, 210 South 33 Street, Philadelphia, PA 19104, USA
| | - Christopher B. Rodell
- Department of Bioengineering, University of Pennsylvania, 240 Skirkanich Hall, 210 South 33 Street, Philadelphia, PA 19104, USA
| | - Iris L. Kim
- Department of Bioengineering, University of Pennsylvania, 240 Skirkanich Hall, 210 South 33 Street, Philadelphia, PA 19104, USA
| | - Ryan J. Wade
- Department of Bioengineering, University of Pennsylvania, 240 Skirkanich Hall, 210 South 33 Street, Philadelphia, PA 19104, USA
| | - J.A. Burdick
- Department of Bioengineering, University of Pennsylvania, 240 Skirkanich Hall, 210 South 33 Street, Philadelphia, PA 19104, USA
| |
Collapse
|
24
|
Tuin SA, Pourdeyhimi B, Loboa EG. Interconnected, microporous hollow fibers for tissue engineering: Commercially relevant, industry standard scale-up manufacturing. J Biomed Mater Res A 2013. [DOI: 10.1002/jbm.a.35002] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/23/2023]
Affiliation(s)
- Stephen A. Tuin
- Joint Department of Biomedical Engineering; at the University of North Carolina at Chapel Hill and North Carolina State University; 4208B EBIII, CB 7115, 911 Oval Raleigh, NC 27695
| | - Behnam Pourdeyhimi
- Nonwovens Cooperative Research Center, The Nonwovens Institute, North Carolina State University; 1000 Main Campus Drive Raleigh North Carolina 27695
| | - Elizabeth G. Loboa
- Joint Department of Biomedical Engineering; at the University of North Carolina at Chapel Hill and North Carolina State University; 4208B EBIII, CB 7115, 911 Oval Raleigh, NC 27695
- Materials Science Engineering; North Carolina State University; EB1 911 Partners Way Raleigh North Carolina 27695
| |
Collapse
|
25
|
Chainani A, Hippensteel KJ, Kishan A, Garrigues NW, Ruch DS, Guilak F, Little D. Multilayered electrospun scaffolds for tendon tissue engineering. Tissue Eng Part A 2013; 19:2594-604. [PMID: 23808760 DOI: 10.1089/ten.tea.2013.0165] [Citation(s) in RCA: 83] [Impact Index Per Article: 7.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/30/2022] Open
Abstract
Full-thickness rotator cuff tears are one of the most common causes of shoulder pain in people over the age of 65. High retear rates and poor functional outcomes are common after surgical repair, and currently available extracellular matrix scaffold patches have limited abilities to enhance new tendon formation. In this regard, tissue-engineered scaffolds may provide a means to improve repair of rotator cuff tears. Electrospinning provides a versatile method for creating nanofibrous scaffolds with controlled architectures, but several challenges remain in its application to tissue engineering, such as cell infiltration through the full thickness of the scaffold as well as control of cell growth and differentiation. Previous studies have shown that ligament-derived extracellular matrix may enhance differentiation toward a tendon or ligament phenotype by human adipose stem cells (hASCs). In this study, we investigated the use of tendon-derived extracellular matrix (TDM)-coated electrospun multilayered scaffolds compared to fibronectin (FN) or phosphate-buffered saline (PBS) coating for use in rotator cuff tendon tissue engineering. Multilayered poly(ɛ-caprolactone) scaffolds were prepared by sequentially collecting electrospun layers onto the surface of a grounded saline solution into a single scaffold. Scaffolds were then coated with TDM, FN, or PBS and seeded with hASCs. Scaffolds were maintained without exogenous growth factors for 28 days in culture and evaluated for protein content (by immunofluorescence and biochemical assay), markers of tendon differentiation, and tensile mechanical properties. The collagen content was greatest by day 28 in TDM-scaffolds. Gene expression of type I collagen, decorin, and tenascin C increased over time, with no effect of scaffold coating. Sulfated glycosaminoglycan and dsDNA contents increased over time in culture, but there was no effect of scaffold coating. The Young's modulus did not change over time, but yield strain increased with time in culture. Histology demonstrated cell infiltration through the full thickness of all scaffolds and immunofluorescence demonstrated greater expression of type I, but not type III collagen through the full thickness of the scaffold in TDM-scaffolds compared to other treatment groups. Together, these data suggest that nonaligned multilayered electrospun scaffolds permit tenogenic differentiation by hASCs and that TDM may promote some aspects of this differentiation.
Collapse
Affiliation(s)
- Abby Chainani
- 1 Department of Orthopaedic Surgery, Duke University Medical Center , Durham, North Carolina
| | | | | | | | | | | | | |
Collapse
|
26
|
Xu Y, Wu J, Wang H, Li H, Di N, Song L, Li S, Li D, Xiang Y, Liu W, Mo X, Zhou Q. Fabrication of electrospun poly(L-lactide-co-ε-caprolactone)/collagen nanoyarn network as a novel, three-dimensional, macroporous, aligned scaffold for tendon tissue engineering. Tissue Eng Part C Methods 2013; 19:925-36. [PMID: 23557537 DOI: 10.1089/ten.tec.2012.0328] [Citation(s) in RCA: 79] [Impact Index Per Article: 7.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/13/2022] Open
Abstract
Tissue engineering techniques using novel scaffolding materials offer potential alternatives for managing tendon disorders. An ideal tendon tissue engineered scaffold should mimic the three-dimensional (3D) structure of the natural extracellular matrix (ECM) of the native tendon. Here, we propose a novel electrospun nanoyarn network that is morphologically and structurally similar to the ECM of native tendon tissues. The nanoyarn, random nanofiber, and aligned nanofiber scaffolds of a synthetic biodegradable polymer, poly(L-lactide-co-ε-caprolactone) [P(LLA-CL)], and natural collagen I complex were fabricated using electrospinning. These scaffolds were characterized in terms of fiber morphology, pore size, porosity, and chemical and mechanical properties for the purpose of culturing tendon cells (TCs) for tendon tissue engineering. The results indicated a fiber diameter of 632 ± 81 nm for the random nanofiber scaffold, 643 ± 97 nm for the aligned nanofiber scaffold, and 641 ± 68 nm for the nanoyarn scaffold. The yarn in the nanoyarn scaffold was twisted by many nanofibers similar to the structure and inherent nanoscale organization of tendons, indicating an increase in the diameter of 9.51 ± 3.62 μm. The nanoyarn scaffold also contained 3D aligned microstructures with large interconnected pores and high porosity. Fourier transform infrared analyses revealed the presence of collagen in the three scaffolds. The mechanical properties of the sample scaffolds indicated that the scaffolds had desirable mechanical properties for tissue regeneration. Further, the results revealed that TC proliferation and infiltration, and the expression of tendon-related ECM genes, were significantly enhanced on the nanoyarn scaffold compared with that on the random nanofiber and aligned nanofiber scaffolds. This study demonstrates that electrospun P(LLA-CL)/collagen nanoyarn is a novel, 3D, macroporous, aligned scaffold that has potential application in tendon tissue engineering.
Collapse
Affiliation(s)
- Yuan Xu
- 1 Department of Orthopaedics, Southwest Hospital, Third Military Medical University , Chongqing, China
| | | | | | | | | | | | | | | | | | | | | | | |
Collapse
|
27
|
Rodríguez K, Sundberg J, Gatenholm P, Renneckar S. Electrospun nanofibrous cellulose scaffolds with controlled microarchitecture. Carbohydr Polym 2012; 100:143-9. [PMID: 24188848 DOI: 10.1016/j.carbpol.2012.12.037] [Citation(s) in RCA: 25] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/01/2012] [Revised: 11/20/2012] [Accepted: 12/14/2012] [Indexed: 10/27/2022]
Abstract
Introducing porosity in electrospun scaffolds is critical to improve cell penetration and nutrient diffusion for tissue engineering. Nanofibrous cellulose scaffolds were prepared by electrospinning cellulose acetate (CA) followed by saponification to regenerate cellulose. Using a computer-assisted design approach, scaffolds underwent laser ablation resulting in pores with diameters between 50 and 300 μm without damaging or modifying the surrounding scaffold area. A new mineralization method was employed in conjunction with microablation using commercial phosphate buffered saline (PBS) to soak carboxymethylcellulose surface-modified electrospun scaffolds. The resulting crystals within the scaffold on the interior of the pore had a calcium to phosphate ratio of 1.56, similar to hydroxyapatite. It was observed that porosity of the cellulose scaffolds enhanced osteoblast cell attachment at the edge of the pores, while mineralization enhanced overall cell density.
Collapse
Affiliation(s)
- Katia Rodríguez
- Department of Materials Science, Virginia Tech, Blacksburg, VA 24060, USA
| | | | | | | |
Collapse
|
28
|
Szpalski C, Wetterau M, Barr J, Warren SM. Bone tissue engineering: current strategies and techniques--part I: Scaffolds. TISSUE ENGINEERING PART B-REVIEWS 2012; 18:246-57. [PMID: 22029448 DOI: 10.1089/ten.teb.2011.0427] [Citation(s) in RCA: 104] [Impact Index Per Article: 8.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 12/16/2022]
Abstract
Bone repair and regeneration is a dynamic process that involves a complex interplay between the (1) ground substance, (2) cells, and (3) milieu. While each constituent is integral to the final product, it is often helpful to consider each component individually. Therefore, we created a two-part review to examine scaffolds and cells' roles in bone tissue engineering. In Part I, we review the myriad of materials use for in vivo bone engineering. In Part II, we discuss the variety cell types (e.g., osteocytes, osteoblasts, osteoclasts, chondrocytes, mesenchymal stem cells, and vasculogenic cells) that are seeded upon or recruited to these scaffolds. In Part III, we discuss the optimization of the microenvironment. The biochemical processes and sequence of events that guide matrix production, cellular activation, and ossification are vital to developing successful bone tissue engineering strategies and are thus succinctly reviewed herein.
Collapse
Affiliation(s)
- Caroline Szpalski
- Department of Plastic Surgery, Institute of Reconstructive Plastic Surgery Laboratory, New York, New York, USA
| | | | | | | |
Collapse
|
29
|
Canbolat MF, Tang C, Bernacki SH, Pourdeyhimi B, Khan S. Mammalian cell viability in electrospun composite nanofiber structures. Macromol Biosci 2011; 11:1346-56. [PMID: 21984502 DOI: 10.1002/mabi.201100108] [Citation(s) in RCA: 38] [Impact Index Per Article: 2.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/19/2011] [Revised: 05/21/2011] [Indexed: 01/18/2023]
Abstract
Incorporation of mammalian cells into nanofibers (cell electrospinning) and multilayered cell-nanofiber structures (cell layering) via electrospinning are promising techniques for tissue engineering applications. We investigate the viability of 3T3-L1 mouse fibroblasts after incorporation into poly(vinyl alcohol) nanofibers and multilayering with poly(caprolactone) nanofibers and analyze the possible factors that affect cell viability. We observe that cells do not survive cell electrospinning but survive cell layering. Assessing the factors involved in cell electrospinning, we find that dehydration and fiber stretching are the main causes of cell death. In cell layering, the choice of solvent is critical, as residual solvent in the electrospun fibers could be detrimental to the cells.
Collapse
Affiliation(s)
- Mehmet Fatih Canbolat
- Fiber and Polymer Science, College of Textiles North Carolina State University, 3427 College of Textiles, Raleigh, North Carolina 27695-8301, USA
| | | | | | | | | |
Collapse
|
30
|
Gillette BM, Rossen NS, Das N, Leong D, Wang M, Dugar A, Sia SK. Engineering extracellular matrix structure in 3D multiphase tissues. Biomaterials 2011; 32:8067-76. [PMID: 21840047 DOI: 10.1016/j.biomaterials.2011.05.043] [Citation(s) in RCA: 60] [Impact Index Per Article: 4.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/29/2011] [Accepted: 05/12/2011] [Indexed: 01/12/2023]
Abstract
In native tissues, microscale variations in the extracellular matrix (ECM) structure can drive different cellular behaviors. Although control over ECM structure could prove useful in tissue engineering and in studies of cellular behavior, isotropic 3D matrices poorly replicate variations in local microenvironments. In this paper, we demonstrate a method to engineer local variations in the density and size of collagen fibers throughout 3D tissues. The results showed that, in engineered multiphase tissues, the structures of collagen fibers in both the bulk ECM phases (as measured by mesh size and width of fibers) as well as at tissue interfaces (as measured by density of fibers and thickness of tissue interfaces) could be modulated by varying the collagen concentrations and gelling temperatures. As the method makes use of a previously published technique for tissue bonding, we also confirmed that significant adhesion strength at tissue interfaces was achieved under all conditions tested. Hence, this study demonstrates how collagen fiber structures can be engineered within all regions of a multiphase tissue scaffold by exploiting knowledge of collagen assembly, and presents an approach to engineer local collagen structure that complements methods such as flow alignment and electrospinning.
Collapse
Affiliation(s)
- Brian M Gillette
- Department of Biomedical Engineering Columbia University, New York, NY 10027, USA
| | | | | | | | | | | | | |
Collapse
|
31
|
Cell adhesive and growth behavior on electrospun nanofibrous scaffolds by designed multifunctional composites. Colloids Surf B Biointerfaces 2011; 84:26-34. [DOI: 10.1016/j.colsurfb.2010.12.005] [Citation(s) in RCA: 37] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/23/2010] [Revised: 12/02/2010] [Accepted: 12/02/2010] [Indexed: 11/20/2022]
|
32
|
Hong JK, Madihally SV. Next generation of electrosprayed fibers for tissue regeneration. TISSUE ENGINEERING. PART B, REVIEWS 2011; 17:125-42. [PMID: 21210761 PMCID: PMC3062468 DOI: 10.1089/ten.teb.2010.0552] [Citation(s) in RCA: 53] [Impact Index Per Article: 4.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 09/17/2010] [Accepted: 01/06/2011] [Indexed: 11/12/2022]
Abstract
Electrospinning is a widely established polymer-processing technology that allows generation of fibers (in nanometer to micrometer size) that can be collected to form nonwoven structures. By choosing suitable process parameters and appropriate solvent systems, fiber size can be controlled. Since the technology allows the possibility of tailoring the mechanical properties and biological properties, there has been a significant effort to adapt the technology in tissue regeneration and drug delivery. This review focuses on recent developments in adapting this technology for tissue regeneration applications. In particular, different configurations of nozzles and collector plates are summarized from the view of cell seeding and distribution. Further developments in obtaining thick layers of tissues and thin layered membranes are discussed. Recent advances in porous structure spatial architecture parameters such as pore size, fiber size, fiber stiffness, and matrix turnover are summarized. In addition, possibility of developing simple three-dimensional models using electrosprayed fibers that can be utilized in routine cell culture studies is described.
Collapse
Affiliation(s)
- Jong Kyu Hong
- School of Chemical Engineering, Oklahoma State University, Stillwater, Oklahoma, USA
| | | |
Collapse
|
33
|
Lin SD, Huang SH, Lin YN, Wu SH, Chang HW, Lin TM, Chai CY, Lai CS. Engineering adipose tissue from uncultured human adipose stromal vascular fraction on collagen matrix and gelatin sponge scaffolds. Tissue Eng Part A 2011; 17:1489-98. [PMID: 21247363 DOI: 10.1089/ten.tea.2010.0688] [Citation(s) in RCA: 29] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/12/2022] Open
Abstract
Adipogenic potential was evaluated in uncultured stromal vascular fraction (SVF) loaded onto porous 3D collagen matrix and gelatin sponge scaffolds with predefined shapes. The SVF was isolated from 16 freshly lipectomized fat. Mean cell number was 6.0±4.68×10(7) cells/mL, and mean cell viability was 72%. Flow cytometric analysis revealed adipose-derived stromal cells (CD31(-), CD34(-/+), CD45(-), CD90(+), CD105(-), CD146(-), and CD166(+)) in the SVF. Three hours after harvest of fat, 200 μL of isolated SVF was loaded onto an experimental scaffold (4 mg in weight) and cultured in Dulbecco's modified Eagle's medium. Examination of the construct under an inverted light microscope and a scanning electron microscope demonstrated adequate seeding and active proliferation of the SVF cells on pore surfaces. Cells grew to varying sizes in clusters or in strands. On day 28, histologic study of the constructs by H&E staining revealed viable adipocytes in the microstructure. Positive Oil-Red O stain confirmed lipid accumulation in mature adipocytes. The presence of human adipocytes was further assessed by the presence of genomic DNA detected by GAPDH gene and by the mRNA expression of peroxisome proliferator activated receptor-γ, and lipoprotein lipase. The results demonstrated that new adipose tissue can be regenerated by seeding freshly isolated, uncultured SVF on 3D porous collagen matrix and gelatin sponge scaffolds.
Collapse
Affiliation(s)
- Sin-Daw Lin
- Division of Plastic Surgery, Department of Surgery, Kaohsiung Medical University Hospital, Kaohsiung, Taiwan.
| | | | | | | | | | | | | | | |
Collapse
|
34
|
Creating Electrospun Nanofiber-Based Biomimetic Scaffolds for Bone Regeneration. BIOMEDICAL APPLICATIONS OF POLYMERIC NANOFIBERS 2011. [DOI: 10.1007/12_2011_131] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 12/22/2022]
|
35
|
McCullen SD, Haslauer CM, Loboa EG. Fiber-reinforced scaffolds for tissue engineering and regenerative medicine: use of traditional textile substrates to nanofibrous arrays. ACTA ACUST UNITED AC 2010. [DOI: 10.1039/c0jm01443e] [Citation(s) in RCA: 55] [Impact Index Per Article: 3.9] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/24/2022]
|
36
|
Nam J, Huang Y, Agarwal S, Lannutti J. Improved cellular infiltration in electrospun fiber via engineered porosity. TISSUE ENGINEERING 2007; 13:2249-57. [PMID: 17536926 PMCID: PMC4948987 DOI: 10.1089/ten.2006.0306] [Citation(s) in RCA: 329] [Impact Index Per Article: 19.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 12/16/2022]
Abstract
Small pore sizes inherent to electrospun matrices can hinder efficient cellular ingrowth. To facilitate infiltration while retaining its extracellular matrix-like character, electrospinning was combined with salt leaching to produce a scaffold having deliberate, engineered delaminations. We made elegant use of a specific randomizing component of the electrospinning process, the Taylor Cone and the falling fiber beneath it, to produce a uniform, well-spread distribution of salt particles. After 3 weeks of culture, up to 4 mm of cellular infiltration was observed, along with cellular coverage of up to 70% within the delaminations. To our knowledge, this represents the first observation of extensive cellular infiltration of electrospun matrices. Infiltration appears to be driven primarily by localized proliferation rather than coordinated cellular locomotion. Cells also moved from the salt-generated porosity into the surrounding electrospun fiber matrix. Given that the details of salt deposition (amount, size, and number density) are far from optimized, the result provides a convincing illustration of the ability of mammalian cells to interact with appropriately tailored electrospun matrices. These layered structures can be precisely fabricated by varying the deposition interval and particle size conceivably to produce in vivo-like gradients in porosity such that the resulting scaffolds better resemble the desired final structure.
Collapse
Affiliation(s)
- Jin Nam
- Department of Materials Science and Engineering, The Ohio State University, Columbus, Ohio 43210, USA
| | | | | | | |
Collapse
|