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Muldoon K, Ahmad Z, Su YC, Tseng FG, Chen X, McLaughlin JAD, Chang MW. A Refined Hot Melt Printing Technique with Real-Time CT Imaging Capability. MICROMACHINES 2022; 13:1794. [PMID: 36296147 PMCID: PMC9609882 DOI: 10.3390/mi13101794] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Subscribe] [Scholar Register] [Received: 08/31/2022] [Revised: 10/18/2022] [Accepted: 10/19/2022] [Indexed: 06/16/2023]
Abstract
Personalised drug delivery systems with the ability to offer real-time imaging and control release are an advancement in diagnostic and therapeutic applications. This allows for a tailored drug dosage specific to the patient with a release profile that offers the optimum therapeutic effect. Coupling this application with medical imaging capabilities, real-time contrast can be viewed to display the interaction with the host. Current approaches towards such novelty produce a drug burst release profile and contrasting agents associated with side effects as a result of poor encapsulation of these components. In this study, a 3D-printed drug delivery matrix with real-time imaging is engineered. Polycaprolactone (PCL) forms the bulk structure and encapsulates tetracycline hydrochloride (TH), an antibiotic drug and Iron Oxide Nanoparticles (IONP, Fe3O4), a superparamagnetic contrasting agent. Hot melt extrusion (HME) coupled with fused deposition modelling (FDM) is utilised to promote the encapsulation of TH and IONP. The effect of additives on the formation of micropores (10-20 µm) on the 3D-printed surface was investigated. The high-resolution process demonstrated successful encapsulation of both bioactive and nano components to present promising applications in drug delivery systems, medical imaging and targeted therapy.
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Affiliation(s)
- Kirsty Muldoon
- Nanotechnology and Integrated Bioengineering Centre (NIBEC), University of Ulster, Belfast BT15 1ED, UK
| | - Zeeshan Ahmad
- School of Pharmacy, De Montfort University, Leicester LE1 9BH, UK
| | - Yu-Chuan Su
- Department of Engineering and System Science, National Tsing Hua University, Hsinchu 300044, Taiwan
| | - Fan-Gang Tseng
- Institute of NanoEngineering and MicroSystem, National Tsing Hua University, Hsinchu 300044, Taiwan
- Department of Engineering and System Science, Frontier Research Center on Fundamental and Applied Sciences of Matters, National Tsing Hua University, Hsinchu 300044, Taiwan
| | - Xing Chen
- Key Laboratory for Biomedical Engineering of Education Ministry of China, Zhejiang University, Hangzhou 310027, China
| | - James A. D. McLaughlin
- Nanotechnology and Integrated Bioengineering Centre (NIBEC), University of Ulster, Belfast BT15 1ED, UK
| | - Ming-Wei Chang
- Nanotechnology and Integrated Bioengineering Centre (NIBEC), University of Ulster, Belfast BT15 1ED, UK
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2
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Mazalan MB, Ramlan MAB, Shin JH, Ohashi T. Effect of Geometric Curvature on Collective Cell Migration in Tortuous Microchannel Devices. MICROMACHINES 2020; 11:E659. [PMID: 32630662 PMCID: PMC7408538 DOI: 10.3390/mi11070659] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 06/07/2020] [Revised: 06/27/2020] [Accepted: 06/29/2020] [Indexed: 01/22/2023]
Abstract
Collective cell migration is an essential phenomenon in many naturally occurring pathophysiological processes, as well as in tissue engineering applications. Cells in tissues and organs are known to sense chemical and mechanical signals from the microenvironment and collectively respond to these signals. For the last few decades, the effects of chemical signals such as growth factors and therapeutic agents on collective cell behaviors in the context of tissue engineering have been extensively studied, whereas those of the mechanical cues have only recently been investigated. The mechanical signals can be presented to the constituent cells in different forms, including topography, substrate stiffness, and geometrical constraint. With the recent advancement in microfabrication technology, researchers have gained the ability to manipulate the geometrical constraints by creating 3D structures to mimic the tissue microenvironment. In this study, we simulate the pore curvature as presented to the cells within 3D-engineered tissue-scaffolds by developing a device that features tortuous microchannels with geometric variations. We show that both cells at the front and rear respond to the varying radii of curvature and channel amplitude by altering the collective migratory behavior, including cell velocity, morphology, and turning angle. These findings provide insights into adaptive migration modes of collective cells to better understand the underlying mechanism of cell migration for optimization of the engineered tissue-scaffold design.
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Affiliation(s)
- Mazlee Bin Mazalan
- Graduate School of Engineering, Hokkaido University, Sapporo 060-8628, Japan;
- AMBIENCE, School of Microelectronic Engineering, Universiti Malaysia Perlis, Arau 02600, Perlis, Malaysia
| | | | - Jennifer Hyunjong Shin
- Department of Mechanical Engineering, Korea Advanced Institute of Science & Technology, Daejeon 34141, Korea;
| | - Toshiro Ohashi
- Faculty of Engineering, Hokkaido University, Sapporo 060-8628, Japan;
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3
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Doolin MT, Moriarty RA, Stroka KM. Mechanosensing of Mechanical Confinement by Mesenchymal-Like Cells. Front Physiol 2020; 11:365. [PMID: 32390868 PMCID: PMC7193100 DOI: 10.3389/fphys.2020.00365] [Citation(s) in RCA: 14] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/25/2019] [Accepted: 03/30/2020] [Indexed: 12/13/2022] Open
Abstract
Mesenchymal stem cells (MSCs) and tumor cells have the unique capability to migrate out of their native environment and either home or metastasize, respectively, through extremely heterogeneous environments to a distant location. Once there, they can either aid in tissue regrowth or impart an immunomodulatory effect in the case of MSCs, or form secondary tumors in the case of tumor cells. During these journeys, cells experience physically confining forces that impinge on the cell body and the nucleus, ultimately causing a multitude of cellular changes. Most drastically, confining individual MSCs within hydrogels or confining monolayers of MSCs within agarose wells can sway MSC lineage commitment, while applying a confining compressive stress to metastatic tumor cells can increase their invasiveness. In this review, we seek to understand the signaling cascades that occur as cells sense confining forces and how that translates to behavioral changes, including elongated and multinucleated cell morphologies, novel migrational mechanisms, and altered gene expression, leading to a unique MSC secretome that could hold great promise for anti-inflammatory treatments. Through comparison of these altered behaviors, we aim to discern how MSCs alter their lineage selection, while tumor cells may become more aggressive and invasive. Synthesizing this information can be useful for employing MSCs for therapeutic approaches through systemic injections or tissue engineered grafts, and developing improved strategies for metastatic cancer therapies.
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Affiliation(s)
- Mary T. Doolin
- Fischell Department of Bioengineering, University of Maryland, College Park, College Park, MD, United States
| | - Rebecca A. Moriarty
- Fischell Department of Bioengineering, University of Maryland, College Park, College Park, MD, United States
| | - Kimberly M. Stroka
- Fischell Department of Bioengineering, University of Maryland, College Park, College Park, MD, United States
- Maryland Biophysics Program, University of Maryland, College Park, College Park, MD, United States
- Center for Stem Cell Biology & Regenerative Medicine, University of Maryland, Baltimore, Baltimore, MD, United States
- Marlene and Stewart Greenebaum Comprehensive Cancer Center, University of Maryland, Baltimore, Baltimore, MD, United States
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4
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Ashworth JC, Mehr M, Buxton PG, Best SM, Cameron RE. Optimising collagen scaffold architecture for enhanced periodontal ligament fibroblast migration. JOURNAL OF MATERIALS SCIENCE. MATERIALS IN MEDICINE 2018; 29:166. [PMID: 30392028 PMCID: PMC6223802 DOI: 10.1007/s10856-018-6175-9] [Citation(s) in RCA: 28] [Impact Index Per Article: 4.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 08/13/2018] [Accepted: 10/17/2018] [Indexed: 05/13/2023]
Abstract
Design of cell-free scaffolds for endogenous cell recruitment requires an intimate knowledge of precise relationships between structure and biological function. Here, we use morphological analysis by Micro-CT to identify the key structural features necessary for periodontal ligament fibroblast recruitment into collagen scaffolds. By the combined use of time-lapse imaging and end-point invasion analysis, we distinguish the influences of pore size, pore wall alignment, and pore transport pathways (percolation diameter) on the individual cell migration and bulk invasion characteristics of these fibroblasts. Whereas maximising percolation diameter increased individual cell speed, elongation and directionality, and produced the most rapid bulk cell invasion, a pore size of 100 μm was found to be necessary to ensure an even distribution of cells across the scaffold cross-section. These results demonstrate that control of percolation diameter and pore size may be used respectively to tune the efficiency and uniformity of invasion through macroporous scaffolds. Crucially, however, these observations were subject to the condition of pore wall alignment, with low alignment in the direction of travel producing relatively low cell speeds and limited invasion in all cases. Pore wall alignment should therefore be carefully optimised in the design of scaffolds for cell recruitment, such as that required for periodontal ligament regeneration, as a key determining factor for cell movement.
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Affiliation(s)
- Jennifer C Ashworth
- Department of Materials Science and Metallurgy, University of Cambridge, 27 Charles Babbage Road, Cambridge, CB3 0FS, UK.
- Stem Cell Glycobiology Group, Centre for Biomolecular Sciences, University of Nottingham, NG7 2RD, Nottingham, UK.
| | - Marco Mehr
- Geistlich Pharma AG, Core Technologies, Bahnhofstrasse 40, CH-6110, Wolhusen, Switzerland
| | - Paul G Buxton
- Geistlich Pharma AG, Core Technologies, Bahnhofstrasse 40, CH-6110, Wolhusen, Switzerland
| | - Serena M Best
- Department of Materials Science and Metallurgy, University of Cambridge, 27 Charles Babbage Road, Cambridge, CB3 0FS, UK
| | - Ruth E Cameron
- Department of Materials Science and Metallurgy, University of Cambridge, 27 Charles Babbage Road, Cambridge, CB3 0FS, UK
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5
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Ashworth JC, Mehr M, Buxton PG, Best SM, Cameron RE. Parameterizing the Transport Pathways for Cell Invasion in Complex Scaffold Architectures. Tissue Eng Part C Methods 2016; 22:409-17. [PMID: 26888449 PMCID: PMC4870607 DOI: 10.1089/ten.tec.2015.0483] [Citation(s) in RCA: 15] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/31/2022] Open
Abstract
Interconnecting pathways through porous tissue engineering scaffolds play a vital role in determining nutrient supply, cell invasion, and tissue ingrowth. However, the global use of the term “interconnectivity” often fails to describe the transport characteristics of these pathways, giving no clear indication of their potential to support tissue synthesis. This article uses new experimental data to provide a critical analysis of reported methods for the description of scaffold transport pathways, ranging from qualitative image analysis to thorough structural parameterization using X-ray Micro-Computed Tomography. In the collagen scaffolds tested in this study, it was found that the proportion of pore space perceived to be accessible dramatically changed depending on the chosen method of analysis. Measurements of % interconnectivity as defined in this manner varied as a function of direction and connection size, and also showed a dependence on measurement length scale. As an alternative, a method for transport pathway parameterization was investigated, using percolation theory to calculate the diameter of the largest sphere that can travel to infinite distance through a scaffold in a specified direction. As proof of principle, this approach was used to investigate the invasion behavior of primary fibroblasts in response to independent changes in pore wall alignment and pore space accessibility, parameterized using the percolation diameter. The result was that both properties played a distinct role in determining fibroblast invasion efficiency. This example therefore demonstrates the potential of the percolation diameter as a method of transport pathway parameterization, to provide key structural criteria for application-based scaffold design.
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Affiliation(s)
- Jennifer C Ashworth
- 1 Department of Materials Science and Metallurgy, University of Cambridge , Cambridge, United Kingdom
| | - Marco Mehr
- 2 Geistlich Pharma AG, Core Technologies , Wolhusen, Switzerland
| | - Paul G Buxton
- 2 Geistlich Pharma AG, Core Technologies , Wolhusen, Switzerland
| | - Serena M Best
- 1 Department of Materials Science and Metallurgy, University of Cambridge , Cambridge, United Kingdom
| | - Ruth E Cameron
- 1 Department of Materials Science and Metallurgy, University of Cambridge , Cambridge, United Kingdom
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6
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Tang D, Tare RS, Yang LY, Williams DF, Ou KL, Oreffo ROC. Biofabrication of bone tissue: approaches, challenges and translation for bone regeneration. Biomaterials 2016; 83:363-82. [PMID: 26803405 DOI: 10.1016/j.biomaterials.2016.01.024] [Citation(s) in RCA: 348] [Impact Index Per Article: 43.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/21/2015] [Revised: 12/21/2015] [Accepted: 01/01/2016] [Indexed: 02/08/2023]
Abstract
The rising incidence of bone disorders has resulted in the need for more effective therapies to meet this demand, exacerbated by an increasing ageing population. Bone tissue engineering is seen as a means of developing alternatives to conventional bone grafts for repairing or reconstructing bone defects by combining biomaterials, cells and signalling factors. However, skeletal tissue engineering has not yet achieved full translation into clinical practice as a consequence of several challenges. The use of additive manufacturing techniques for bone biofabrication is seen as a potential solution, with its inherent capability for reproducibility, accuracy and customisation of scaffolds as well as cell and signalling factor delivery. This review highlights the current research in bone biofabrication, the necessary factors for successful bone biofabrication, in addition to the current limitations affecting biofabrication, some of which are a consequence of the limitations of the additive manufacturing technology itself.
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Affiliation(s)
- Daniel Tang
- Centre for Human Development, Stem Cells and Regeneration, Faculty of Medicine, University of Southampton, Southampton, SO16 6YD, United Kingdom
| | - Rahul S Tare
- Centre for Human Development, Stem Cells and Regeneration, Faculty of Medicine, University of Southampton, Southampton, SO16 6YD, United Kingdom; Engineering Sciences, Faculty of Engineering and the Environment, University of Southampton, Southampton, SO17 1BJ, United Kingdom
| | - Liang-Yo Yang
- Department of Physiology, School of Medicine, College of Medicine, Taipei Medical University, Taipei, 110, Taiwan, ROC; Research Centre for Biomedical Devices and Prototyping Production, Taipei Medical University, Taipei, 110, Taiwan, ROC; School of Medicine, College of Medicine, China Medical University, Taichung, 40402, Taiwan, ROC
| | - David F Williams
- Graduate Institute of Biomedical Materials and Tissue Engineering, Taipei Medical University, Taipei, 110, Taiwan, ROC; Institute of Regenerative Medicine, Wake Forest School of Medicine, Winston-Salem, NC, USA
| | - Keng-Liang Ou
- Research Centre for Biomedical Devices and Prototyping Production, Taipei Medical University, Taipei, 110, Taiwan, ROC; Graduate Institute of Biomedical Materials and Tissue Engineering, Taipei Medical University, Taipei, 110, Taiwan, ROC; Research Centre for Biomedical Implants and Microsurgery Devices, Taipei Medical University, Taipei, 110, Taiwan, ROC; Department of Dentistry, Taipei Medical University-Shuang Ho Hospital, New Taipei City, 235, Taiwan, ROC.
| | - Richard O C Oreffo
- Centre for Human Development, Stem Cells and Regeneration, Faculty of Medicine, University of Southampton, Southampton, SO16 6YD, United Kingdom.
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7
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Ashworth JC, Mehr M, Buxton PG, Best SM, Cameron RE. Cell Invasion in Collagen Scaffold Architectures Characterized by Percolation Theory. Adv Healthc Mater 2015; 4:1317-21. [PMID: 25881025 PMCID: PMC4529738 DOI: 10.1002/adhm.201500197] [Citation(s) in RCA: 39] [Impact Index Per Article: 4.3] [Reference Citation Analysis] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/19/2015] [Indexed: 11/21/2022]
Affiliation(s)
- Jennifer C. Ashworth
- Department of Materials Science and Metallurgy University of Cambridge 27 Charles Babbage Road Cambridge CB3 0FS UK
| | - Marco Mehr
- Geistlich Pharma AG Core Technologies Bahnhofstrasse 40 CH‐6110 Wolhusen Switzerland
| | - Paul G. Buxton
- Geistlich Pharma AG Core Technologies Bahnhofstrasse 40 CH‐6110 Wolhusen Switzerland
| | - Serena M. Best
- Department of Materials Science and Metallurgy University of Cambridge 27 Charles Babbage Road Cambridge CB3 0FS UK
| | - Ruth E. Cameron
- Department of Materials Science and Metallurgy University of Cambridge 27 Charles Babbage Road Cambridge CB3 0FS UK
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8
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Snyder JE, Hunger PM, Wang C, Hamid Q, Wegst UGK, Sun W. Combined multi-nozzle deposition and freeze casting process to superimpose two porous networks for hierarchical three-dimensional microenvironment. Biofabrication 2014; 6:015007. [PMID: 24429830 DOI: 10.1088/1758-5082/6/1/015007] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/12/2022]
Abstract
An engineered three-dimensional scaffold with hierarchical porosity and multiple niche microenvironments is produced using a combined multi-nozzle deposition-freeze casting technique. In this paper we present a process to fabricate a scaffold with improved interconnectivity and hierarchical porosity. The scaffold is produced using a two-stage manufacturing process which superimposes a printed porous alginate (Alg) network and a directionally frozen ceramic-polymer matrix. The combination of two processes, multi-nozzle deposition and freeze casting, provides engineering control of the microenvironment of the scaffolds over several length scales; including the addition of lateral porosity and the ratio of polymer to ceramic microstructures. The printed polymer scaffold is submerged in a ceramic-polymer slurry and subsequently, both structures are directionally frozen (freeze cast), superimposing and patterning both microenvironments into a single hierarchical architecture. An optional additional sintering step removes the organic material and densifies the ceramic phase to produce a well-defined network of open pores and a homogenous cell wall material composition. The techniques presented in this contribution address processing challenges, such as structure definition, reproducibility and fine adjustments of unique length scales, which one typically encounters when fabricating topological channels between longitudinal and transverse porous networks.
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Affiliation(s)
- Jessica E Snyder
- Mechanical Engineering and Mechanics, Drexel University, Philadelphia, PA 19104, USA
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9
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Abstract
We describe a protocol for measuring the speed of human neutrophils migrating through small channels, in conditions of mechanical confinement comparable to those experienced by neutrophils migrating through tissues. In such conditions, we find that neutrophils move persistently, at constant speed for tens of minutes, enabling precise measurements at single cells resolution, for large number of cells. The protocol relies on microfluidic devices with small channels in which a solution of chemoattractant and a suspension of isolated neutrophils are loaded in sequence. The migration of neutrophils can be observed for several hours, starting within minutes after loading the neutrophils in the devices. The protocol is divided into four main steps: the fabrication of the microfluidic devices, the separation of neutrophils from whole blood, the preparation of the assay and cell loading, and the analysis of data. We discuss the practical steps for the implementation of the migration assays in biology labs, the adaptation of the protocols to various cell types, including cancer cells, and the supplementary device features required for precise measurements of directionality and persistence during migration.
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Affiliation(s)
- Daniel Irimia
- Massachusetts General Hospital, Harvard Medical School, and Shirners Hospitals for Children, Boston, Massachusetts, USA
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10
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Vrana NE, Dupret-Bories A, Schultz P, Debry C, Vautier D, Lavalle P. Titanium microbead-based porous implants: bead size controls cell response and host integration. Adv Healthc Mater 2014; 3:79-87. [PMID: 23814016 DOI: 10.1002/adhm.201200369] [Citation(s) in RCA: 10] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/18/2012] [Revised: 02/02/2013] [Indexed: 01/03/2023]
Abstract
Openly porous structures in implants are desirable for better integration with the host tissue. Sintered microbead-based titanium implants for oto-rhinolaryngology applications, which create an environment where the cells can migrate in the areas between the microbeads, are developed. This structure promotes fibrovascular tissue formation within the implant in vivo. In this study, it is determine to what extent these events can be controlled by changing the physical environment of the implants both in vitro and in vivo. By cell tracking, it is observed that the size of the beads and the distance between the neighboring beads significantly affect the ability of cells to develop cell-to-cell contacts and to bridge the pores. Live cell staining shows that as the bead size gets smaller, the probability to observe cells that fill the porous areas is higher. This also affects the initial attachment and distribution of the cells and collagen secretion by fibroblasts. Obtaining a fast coverage of the system also enables co-culture systems where, the number and the distribution of the second cell type are boosted by the presence of the first. This concept is utilized to increase the attachment of vascular endothelial cells by an initial layer of fibroblasts. By decreasing the bead diameter, the overall colonization of the implant can be significantly increased in vivo. The effect of bead size has a similar pattern both in rats and rabbits, with faster colonization of smaller bead-based structures. Using smaller beads would improve clinical outcomes as faster integration facilitates the attainment of functionality by the implant.
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Affiliation(s)
- Nihal Engin Vrana
- INSERM, UMR-S 1121, "Biomatériaux et Bioingénierie", 11 rue Humann, F-67085 Strasbourg Cedex, France; Université de Strasbourg, Faculté de Chirurgie Dentaire, 1 place de l'Hôpital, 67000 Strasbourg, France.
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11
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Vrana NE, Dupret-Bories A, Chaubaroux C, Rieger E, Debry C, Vautier D, Metz-Boutigue MH, Lavalle P. Multi-scale modification of metallic implants with pore gradients, polyelectrolytes and their indirect monitoring in vivo. J Vis Exp 2013:e50533. [PMID: 23851618 DOI: 10.3791/50533] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/31/2022] Open
Abstract
Metallic implants, especially titanium implants, are widely used in clinical applications. Tissue in-growth and integration to these implants in the tissues are important parameters for successful clinical outcomes. In order to improve tissue integration, porous metallic implants have being developed. Open porosity of metallic foams is very advantageous, since the pore areas can be functionalized without compromising the mechanical properties of the whole structure. Here we describe such modifications using porous titanium implants based on titanium microbeads. By using inherent physical properties such as hydrophobicity of titanium, it is possible to obtain hydrophobic pore gradients within microbead based metallic implants and at the same time to have a basement membrane mimic based on hydrophilic, natural polymers. 3D pore gradients are formed by synthetic polymers such as Poly-L-lactic acid (PLLA) by freeze-extraction method. 2D nanofibrillar surfaces are formed by using collagen/alginate followed by a crosslinking step with a natural crosslinker (genipin). This nanofibrillar film was built up by layer by layer (LbL) deposition method of the two oppositely charged molecules, collagen and alginate. Finally, an implant where different areas can accommodate different cell types, as this is necessary for many multicellular tissues, can be obtained. By, this way cellular movement in different directions by different cell types can be controlled. Such a system is described for the specific case of trachea regeneration, but it can be modified for other target organs. Analysis of cell migration and the possible methods for creating different pore gradients are elaborated. The next step in the analysis of such implants is their characterization after implantation. However, histological analysis of metallic implants is a long and cumbersome process, thus for monitoring host reaction to metallic implants in vivo an alternative method based on monitoring CGA and different blood proteins is also described. These methods can be used for developing in vitro custom-made migration and colonization tests and also be used for analysis of functionalized metallic implants in vivo without histology.
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Knight T, Basu J, Rivera EA, Spencer T, Jain D, Payne R. Fabrication of a multi-layer three-dimensional scaffold with controlled porous micro-architecture for application in small intestine tissue engineering. Cell Adh Migr 2013; 7:267-74. [PMID: 23563499 DOI: 10.4161/cam.24351] [Citation(s) in RCA: 21] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/13/2022] Open
Abstract
Various methods can be employed to fabricate scaffolds with characteristics that promote cell-to-material interaction. This report examines the use of a novel technique combining compression molding with particulate leaching to create a unique multi-layered scaffold with differential porosities and pore sizes that provides a high level of control to influence cell behavior. These cell behavioral responses were primarily characterized by bridging and penetration of two cell types (epithelial and smooth muscle cells) on the scaffold in vitro. Larger pore sizes corresponded to an increase in pore penetration, and a decrease in pore bridging. In addition, smaller cells (epithelial) penetrated further into the scaffold than larger cells (smooth muscle cells). In vivo evaluation of a multi-layered scaffold was well tolerated for 75 d in a rodent model. This data shows the ability of the components of multi-layered scaffolds to influence cell behavior, and demonstrates the potential for these scaffolds to promote desired tissue outcomes in vivo.
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