1
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Ashworth JC, Cox TR. The importance of 3D fibre architecture in cancer and implications for biomaterial model design. Nat Rev Cancer 2024; 24:461-479. [PMID: 38886573 DOI: 10.1038/s41568-024-00704-8] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Accepted: 05/07/2024] [Indexed: 06/20/2024]
Abstract
The need for improved prediction of clinical response is driving the development of cancer models with enhanced physiological relevance. A new concept of 'precision biomaterials' is emerging, encompassing patient-mimetic biomaterial models that seek to accurately detect, treat and model cancer by faithfully recapitulating key microenvironmental characteristics. Despite recent advances allowing tissue-mimetic stiffness and molecular composition to be replicated in vitro, approaches for reproducing the 3D fibre architectures found in tumour extracellular matrix (ECM) remain relatively unexplored. Although the precise influences of patient-specific fibre architecture are unclear, we summarize the known roles of tumour fibre architecture, underlining their implications in cell-matrix interactions and ultimately clinical outcome. We then explore the challenges in reproducing tissue-specific 3D fibre architecture(s) in vitro, highlighting relevant biomaterial fabrication techniques and their benefits and limitations. Finally, we discuss imaging and image analysis techniques (focussing on collagen I-optimized approaches) that could hold the key to mapping tumour-specific ECM into high-fidelity biomaterial models. We anticipate that an interdisciplinary approach, combining materials science, cancer research and image analysis, will elucidate the role of 3D fibre architecture in tumour development, leading to the next generation of patient-mimetic models for mechanistic studies and drug discovery.
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Affiliation(s)
- J C Ashworth
- School of Veterinary Medicine & Science, Sutton Bonington Campus, University of Nottingham, Leicestershire, UK.
- Biodiscovery Institute, School of Medicine, University of Nottingham, Nottingham, UK.
- Cancer Ecosystems Program, The Garvan Institute of Medical Research, Darlinghurst, New South Wales, Australia.
| | - T R Cox
- Cancer Ecosystems Program, The Garvan Institute of Medical Research, Darlinghurst, New South Wales, Australia.
- The Kinghorn Cancer Centre, Darlinghurst, New South Wales, Australia.
- School of Clinical Medicine, St Vincent's Healthcare Clinical Campus, UNSW Medicine and Health, UNSW Sydney, Sydney, New South Wales, Australia.
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2
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Song X, Philpott MA, Best SM, Cameron RE. Controlling the Architecture of Freeze-Dried Collagen Scaffolds with Ultrasound-Induced Nucleation. Polymers (Basel) 2024; 16:213. [PMID: 38257012 PMCID: PMC10820667 DOI: 10.3390/polym16020213] [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: 11/27/2023] [Revised: 01/04/2024] [Accepted: 01/05/2024] [Indexed: 01/24/2024] Open
Abstract
Collagen is a naturally occurring polymer that can be freeze-dried to create 3D porous scaffold architectures for potential application in tissue engineering. The process comprises the freezing of water in an aqueous slurry followed by sublimation of the ice via a pre-determined temperature-pressure regime and these parameters determine the arrangement, shape and size of the ice crystals. However, ice nucleation is a stochastic process, and this has significant and inherent limitations on the ability to control scaffold structures both within and between the fabrication batches. In this paper, we demonstrate that it is possible to overcome the disadvantages of the stochastic process via the use of low-frequency ultrasound (40 kHz) to trigger nucleation, on-demand, in type I insoluble bovine collagen slurries. The application of ultrasound was found to define the nucleation temperature of collagen slurries, precisely tailoring the pore architecture and providing important new structural and mechanistic insights. The parameter space includes reduction in average pore size and narrowing of pore size distributions while maintaining the percolation diameter. A set of core principles are identified that highlight the huge potential of ultrasound to finely tune the scaffold architecture and revolutionise the reproducibility of the scaffold fabrication protocol.
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Affiliation(s)
| | | | | | - Ruth E. Cameron
- Department of Materials Science and Metallurgy, University of Cambridge, Cambridge CB3 0FS, UK; (X.S.); (S.M.B.)
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3
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Cyr JA, Colzani M, Bayraktar S, Köhne M, Bax DV, Graup V, Farndale R, Sinha S, Best SM, Cameron RE. Extracellular macrostructure anisotropy improves cardiac tissue-like construct function and phenotypic cellular maturation. BIOMATERIALS ADVANCES 2023; 155:213680. [PMID: 37944449 DOI: 10.1016/j.bioadv.2023.213680] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 03/21/2023] [Revised: 10/02/2023] [Accepted: 10/30/2023] [Indexed: 11/12/2023]
Abstract
Regenerative cardiac tissue is a promising field of study with translational potential as a therapeutic option for myocardial repair after injury, however, poor electrical and contractile function has limited translational utility. Emerging research suggests scaffolds that recapitulate the structure of the native myocardium improve physiological function. Engineered cardiac constructs with anisotropic extracellular architecture demonstrate improved tissue contractility, signaling synchronicity, and cellular organization when compared to constructs with reduced architectural order. The complexity of scaffold fabrication, however, limits isolated variation of individual structural and mechanical characteristics. Thus, the isolated impact of scaffold macroarchitecture on tissue function is poorly understood. Here, we produce isotropic and aligned collagen scaffolds seeded with embryonic stem cell derived cardiomyocytes (hESC-CM) while conserving all confounding physio-mechanical features to independently assess the effects of macroarchitecture on tissue function. We quantified spatiotemporal tissue function through calcium signaling and contractile strain. We further examined intercellular organization and intracellular development. Aligned tissue constructs facilitated improved signaling synchronicity and directional contractility as well as dictated uniform cellular alignment. Cells on aligned constructs also displayed phenotypic and genetic markers of increased maturity. Our results isolate the influence of scaffold macrostructure on tissue function and inform the design of optimized cardiac tissue for regenerative and model medical systems.
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Affiliation(s)
- Jamie A Cyr
- Department of Materials Science & Metallurgy, Cambridge University, 27 Charles Babbage Road, Cambridge CB3 0FS, UK
| | - Maria Colzani
- Wellcome-MRC Cambridge Stem Cell Institute, Cambridge University, Jeffrey Cheah Biomedical Centre, Puddicombe Way, Cambridge CB2 0AW, UK
| | - Semih Bayraktar
- Wellcome-MRC Cambridge Stem Cell Institute, Cambridge University, Jeffrey Cheah Biomedical Centre, Puddicombe Way, Cambridge CB2 0AW, UK
| | - Maria Köhne
- Wellcome-MRC Cambridge Stem Cell Institute, Cambridge University, Jeffrey Cheah Biomedical Centre, Puddicombe Way, Cambridge CB2 0AW, UK
| | - Daniel V Bax
- Department of Materials Science & Metallurgy, Cambridge University, 27 Charles Babbage Road, Cambridge CB3 0FS, UK
| | - Vera Graup
- Department of Materials Science & Metallurgy, Cambridge University, 27 Charles Babbage Road, Cambridge CB3 0FS, UK
| | - Richard Farndale
- Department of Biochemistry, Cambridge University, Hopkins Building Tennis Court Road, Cambridge CB2 1QW, UK
| | - Sanjay Sinha
- Wellcome-MRC Cambridge Stem Cell Institute, Cambridge University, Jeffrey Cheah Biomedical Centre, Puddicombe Way, Cambridge CB2 0AW, UK.
| | - Serena M Best
- Department of Materials Science & Metallurgy, Cambridge University, 27 Charles Babbage Road, Cambridge CB3 0FS, UK.
| | - Ruth E Cameron
- Department of Materials Science & Metallurgy, Cambridge University, 27 Charles Babbage Road, Cambridge CB3 0FS, UK.
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4
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Meyer N, Bax DV, Beck J, Cameron RE, Best SM. Adjusting the physico-chemical properties of collagen scaffolds to accommodate primary osteoblasts and endothelial cells. Regen Biomater 2023; 10:rbad015. [PMID: 36937897 PMCID: PMC10019812 DOI: 10.1093/rb/rbad015] [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: 09/08/2022] [Revised: 12/08/2022] [Accepted: 01/09/2023] [Indexed: 03/12/2023] Open
Abstract
Collagen-based biomaterials are used widely as tissue engineering scaffolds because of their excellent bioactivity and their similarity to the natural ECM. The regeneration of healthy bone tissue requires simultaneous support for both osteoblasts and, where angiogenesis is intended, endothelial cells. Hence it is important to tailor carefully the biochemical and structural characteristics of the scaffold to suit the needs of each cell type. This work describes for the first time a systematic study to gain insight into the cell type-specific response of primary human osteoblast (hOBs) and human dermal microvascular endothelial cells (HDMECs) to insoluble collagen-based biomaterials. The behaviour was evaluated on both 2D films and 3D scaffolds, produced using freeze-drying. The collagen was cross-linked at various EDC/NHS concentrations and mono-cultured with hOBs and HDMECs to assess the effect of architectural features and scaffold stabilization on cell behaviour. It was observed that 3D scaffolds cross-linked at 30% of the standard conditions in literature offered an optimal combination of mechanical stiffness and cellular response for both cell types, although endothelial cells were more sensitive to the degree of cross-linking than hOBs. Architectural features have a time-dependent impact on the cell migration profile, with alignment being the most influential parameter overall.
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Affiliation(s)
- Nima Meyer
- Department of Materials Science and Metallurgy, University of Cambridge, Cambridge CB3 0FS, UK
| | | | - Jochen Beck
- Geistlich Pharma AG, Product Development, Wolhusen, Switzerland
| | - Ruth E Cameron
- Department of Materials Science and Metallurgy, University of Cambridge, Cambridge CB3 0FS, UK
| | - Serena M Best
- Department of Materials Science and Metallurgy, University of Cambridge, Cambridge CB3 0FS, UK
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5
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Complex Architectural Control of Ice-Templated Collagen Scaffolds Using a Predictive Model. Acta Biomater 2022; 153:260-272. [PMID: 36155096 DOI: 10.1016/j.actbio.2022.09.034] [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: 05/23/2022] [Revised: 09/02/2022] [Accepted: 09/14/2022] [Indexed: 11/23/2022]
Abstract
The architectural and physiomechanical properties of regenerative scaffolds have been shown to improve engineered tissue function at both a cellular and tissue level. The fabrication of regenerative three-dimensional scaffolds that precisely replicate the complex hierarchical structure of native tissue, however, remains a challenge. The aim of this work is therefore two-fold: i) demonstrate an innovative multidirectional freeze-casting system to afford precise architectural control of ice-templated collagen scaffolds; and ii) present a predictive simulation as an experimental design tool for bespoke scaffold architecture. We used embedded heat sources within the freeze-casting mold to manipulate the local thermal environment during solidification of ice-templated collagen scaffolds. The resultant scaffolds comprised complex and spatially varied lamellar orientations that correlated with the imposed thermal environment and could be readily controlled by varying the geometry and power of the heat sources. The complex macro-architecture did not interrupt the hierarchical features characteristic of ice-templated scaffolds, but pore orientation had a significant impact on the stiffness of resultant structures under compression. Furthermore, our finite element model (FEM) accurately predicted the thermal environment and illustrated the freezing front topography within the mold during solidification. The lamellar orientation of freeze-cast scaffolds was also predicted using thermal gradient vector direction immediately prior to phase change. In combination our FEM and bespoke freeze-casting system present an exciting opportunity for tailored architectural design of ice-templated regenerative scaffolds that mimic the complex hierarchical environment of the native extracellular matrix. STATEMENT OF SIGNIFICANCE: Biomimetic scaffold structure improves engineered tissue function, but the fabrication of three-dimensional scaffolds that precisely replicate the complex hierarchical structure of native tissue remains a challenge. Here, we leverage the robust relationship between thermal gradients and lamellar orientation of ice-templated collagen scaffolds to develop a multidirectional freeze-casting system with precise control of the thermal environment and consequently the complex lamellar structure of resultant scaffolds. Demonstrating the diversity of our approach, we identify heat source geometry and power as control parameters for complex lamellar orientations. We simultaneously present a finite element model (FEM) that describes the three-dimensional thermal environment during solidification and accurately predicts lamellar structure of resultant scaffolds. The model serves as a design tool for bespoke regenerative scaffolds.
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6
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Meek MC, Best S, Cameron R. The effects of despeckling filters on pore size measurements in collagen scaffold micro-CT data. J Microsc 2021; 284:142-156. [PMID: 34296436 DOI: 10.1111/jmi.13050] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/15/2021] [Accepted: 07/15/2021] [Indexed: 11/30/2022]
Abstract
Micro-CT is often used to assess the characteristics of porous structures such as tissue engineering scaffolds and trabecular bone. Prior to analysis, micro-CT images can be thresholded and filtered to remove noise. Scaffold pore size affects mechanical properties and biological cell behaviour and is a frequently assessed parameter. This paper identifies and characterizes an artefact affecting a commonly used filter which erroneously increases mean pore size. The 3D sweep despeckling filter removes all but the largest object within a volume of interest, and therefore deletes any disconnected objects located at the periphery, increasing measured mean pore size. This artefact is characterized, and effective methods to mitigate its effects are devised, involving despeckling a sufficiently large volume of interest, then reducing the volume of interest in size to remove the error prior to analysis. Techniques to effectively apply this method to other data sets are described. This method eliminates the artefact but is time-consuming and computationally expensive. Alternative, more economical filters which remove objects below a specified size are also assessed but are shown to be affected by the same artefact. These results will help to guide the implementation of future studies investigating the effects of pore size.
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Affiliation(s)
- Matt C Meek
- Department of Materials Science and Metallurgy, University of Cambridge, Cambridge, UK
| | - Serena Best
- Department of Materials Science and Metallurgy, University of Cambridge, Cambridge, UK
| | - Ruth Cameron
- Department of Materials Science and Metallurgy, University of Cambridge, Cambridge, UK
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7
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Sheppard G, Tassenberg K, Nenchev B, Strickland J, Mesalam R, Shepherd J, Williams H. GAKTpore: Stereological Characterisation Methods for Porous Foams in Biomedical Applications. MATERIALS (BASEL, SWITZERLAND) 2021; 14:1269. [PMID: 33800080 PMCID: PMC7962185 DOI: 10.3390/ma14051269] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 11/30/2020] [Revised: 03/02/2021] [Accepted: 03/04/2021] [Indexed: 11/17/2022]
Abstract
In tissue engineering, scaffolds are a key component that possess a highly elaborate pore structure. Careful characterisation of such porous structures enables the prediction of a variety of large-scale biological responses. In this work, a rapid, efficient, and accurate methodology for 2D bulk porous structure analysis is proposed. The algorithm, "GAKTpore", creates a morphology map allowing quantification and visualisation of spatial feature variation. The software achieves 99.6% and 99.1% mean accuracy for pore diameter and shape factor identification, respectively. There are two main algorithm novelties within this work: (1) feature-dependant homogeneity map; (2) a new waviness function providing insights into the convexity/concavity of pores, important for understanding the influence on cell adhesion and proliferation. The algorithm is applied to foam structures, providing a full characterisation of a 10 mm diameter SEM micrograph (14,784 × 14,915 px) with 190,249 pores in ~9 min and has elucidated new insights into collagen scaffold formation by relating microstructural formation to the bulk formation environment. This novel porosity characterisation algorithm demonstrates its versatility, where accuracy, repeatability, and time are paramount. Thus, GAKTpore offers enormous potential to optimise and enhance scaffolds within tissue engineering.
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Affiliation(s)
- Gareth Sheppard
- School of Engineering, University of Leicester, Leicester LE1 7RH, UK; (K.T.); (B.N.); (J.S.); (J.S.); (H.W.)
| | - Karl Tassenberg
- School of Engineering, University of Leicester, Leicester LE1 7RH, UK; (K.T.); (B.N.); (J.S.); (J.S.); (H.W.)
| | - Bogdan Nenchev
- School of Engineering, University of Leicester, Leicester LE1 7RH, UK; (K.T.); (B.N.); (J.S.); (J.S.); (H.W.)
| | - Joel Strickland
- School of Engineering, University of Leicester, Leicester LE1 7RH, UK; (K.T.); (B.N.); (J.S.); (J.S.); (H.W.)
| | - Ramy Mesalam
- School of Physics and Astronomy, University of Leicester, Leicester LE1 7RH, UK;
| | - Jennifer Shepherd
- School of Engineering, University of Leicester, Leicester LE1 7RH, UK; (K.T.); (B.N.); (J.S.); (J.S.); (H.W.)
| | - Hugo Williams
- School of Engineering, University of Leicester, Leicester LE1 7RH, UK; (K.T.); (B.N.); (J.S.); (J.S.); (H.W.)
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8
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Xydias D, Ziakas G, Psilodimitrakopoulos S, Lemonis A, Bagli E, Fotsis T, Gravanis A, Tzeranis DS, Stratakis E. Three-dimensional characterization of collagen remodeling in cell-seeded collagen scaffolds via polarization second harmonic generation. BIOMEDICAL OPTICS EXPRESS 2021; 12:1136-1153. [PMID: 33680563 PMCID: PMC7901316 DOI: 10.1364/boe.411501] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 10/02/2020] [Revised: 11/24/2020] [Accepted: 12/01/2020] [Indexed: 05/08/2023]
Abstract
In this study, we use non-linear imaging microscopy to characterize the structural properties of porous collagen-GAG scaffolds (CGS) seeded with human umbilical vein endothelial cells (HUVECs), as well as human mesenchymal stem cells (hMSCs), a co-culture previously reported to form vessel-like structures inside CGS. The evolution of the resulting tissue construct was monitored over 10 days via simultaneous two- and three-photon excited fluorescence microscopy. Time-lapsed 2- and 3-photon excited fluorescence imaging was utilized to monitor the temporal evolution of the vascular-like structures up to 100 µm inside the scaffold up to 10 days post-seeding. 3D polarization-dependent second harmonic generation (PSHG) was utilized to monitor collagen-based scaffold remodeling and determine collagen fibril orientation up to 200 µm inside the scaffold. We demonstrate that polarization-dependent second harmonic generation can provide a novel way to quantify the reorganization of the collagen architecture in CGS simultaneously with key biomechanical interactions between seeded cells and CGS that regulate the formation of vessel-like structures inside 3D tissue constructs. A comparison between samples at different days in vitro revealed that gradually, the scaffolds developed an orthogonal net-like architecture, previously found in real skin.
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Affiliation(s)
- Dionysios Xydias
- Institute of Electronic Structure and Laser, Foundation for Research and Technology-Hellas, Greece
- Department of Materials Science and Technology, School of Sciences and Engineering, University of Crete, Greece
| | - Georgios Ziakas
- Department of Materials Science and Technology, School of Sciences and Engineering, University of Crete, Greece
| | | | - Andreas Lemonis
- Institute of Electronic Structure and Laser, Foundation for Research and Technology-Hellas, Greece
| | - Eleni Bagli
- Department of Biomedical Research, Institute of Molecular Biology and Biotechnology, Foundation for Research and Technology-Hellas, Ioannina, Greece
| | - Theodore Fotsis
- Department of Biomedical Research, Institute of Molecular Biology and Biotechnology, Foundation for Research and Technology-Hellas, Ioannina, Greece
| | - Achille Gravanis
- Institute of Molecular Biology and Biotechnology, Foundation for Research and Technology-Hellas, Greece
- Department of Pharmacology, School of Medicine, University of Crete, Greece
| | - Dimitrios S. Tzeranis
- Institute of Molecular Biology and Biotechnology, Foundation for Research and Technology-Hellas, Greece
- Department of Mechanical and Manufacturing Engineering, University of Cyprus, Cyprus, Greece
| | - Emmanuel Stratakis
- Institute of Electronic Structure and Laser, Foundation for Research and Technology-Hellas, Greece
- Department of Physics, School of Sciences and Engineering, University of Crete, Greece
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9
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Majid QA, Fricker ATR, Gregory DA, Davidenko N, Hernandez Cruz O, Jabbour RJ, Owen TJ, Basnett P, Lukasiewicz B, Stevens M, Best S, Cameron R, Sinha S, Harding SE, Roy I. Natural Biomaterials for Cardiac Tissue Engineering: A Highly Biocompatible Solution. Front Cardiovasc Med 2020; 7:554597. [PMID: 33195451 PMCID: PMC7644890 DOI: 10.3389/fcvm.2020.554597] [Citation(s) in RCA: 53] [Impact Index Per Article: 13.3] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/22/2020] [Accepted: 09/10/2020] [Indexed: 02/06/2023] Open
Abstract
Cardiovascular diseases (CVD) constitute a major fraction of the current major global diseases and lead to about 30% of the deaths, i.e., 17.9 million deaths per year. CVD include coronary artery disease (CAD), myocardial infarction (MI), arrhythmias, heart failure, heart valve diseases, congenital heart disease, and cardiomyopathy. Cardiac Tissue Engineering (CTE) aims to address these conditions, the overall goal being the efficient regeneration of diseased cardiac tissue using an ideal combination of biomaterials and cells. Various cells have thus far been utilized in pre-clinical studies for CTE. These include adult stem cell populations (mesenchymal stem cells) and pluripotent stem cells (including autologous human induced pluripotent stem cells or allogenic human embryonic stem cells) with the latter undergoing differentiation to form functional cardiac cells. The ideal biomaterial for cardiac tissue engineering needs to have suitable material properties with the ability to support efficient attachment, growth, and differentiation of the cardiac cells, leading to the formation of functional cardiac tissue. In this review, we have focused on the use of biomaterials of natural origin for CTE. Natural biomaterials are generally known to be highly biocompatible and in addition are sustainable in nature. We have focused on those that have been widely explored in CTE and describe the original work and the current state of art. These include fibrinogen (in the context of Engineered Heart Tissue, EHT), collagen, alginate, silk, and Polyhydroxyalkanoates (PHAs). Amongst these, fibrinogen, collagen, alginate, and silk are isolated from natural sources whereas PHAs are produced via bacterial fermentation. Overall, these biomaterials have proven to be highly promising, displaying robust biocompatibility and, when combined with cells, an ability to enhance post-MI cardiac function in pre-clinical models. As such, CTE has great potential for future clinical solutions and hence can lead to a considerable reduction in mortality rates due to CVD.
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Affiliation(s)
- Qasim A. Majid
- Faculty of Medicine, National Heart and Lung Institute, Imperial College London, London, United Kingdom
| | - Annabelle T. R. Fricker
- Department of Material Science and Engineering, Faculty of Engineering, University of Sheffield, Sheffield, United Kingdom
| | - David A. Gregory
- Department of Material Science and Engineering, Faculty of Engineering, University of Sheffield, Sheffield, United Kingdom
| | - Natalia Davidenko
- Department of Materials Science and Metallurgy, Cambridge Centre for Medical Materials, University of Cambridge, Cambridge, United Kingdom
| | - Olivia Hernandez Cruz
- Faculty of Medicine, National Heart and Lung Institute, Imperial College London, London, United Kingdom
- Department of Bioengineering, Department of Materials, IBME, Faculty of Engineering, Imperial College London, United Kingdom
| | - Richard J. Jabbour
- Faculty of Medicine, National Heart and Lung Institute, Imperial College London, London, United Kingdom
| | - Thomas J. Owen
- Faculty of Medicine, National Heart and Lung Institute, Imperial College London, London, United Kingdom
| | - Pooja Basnett
- Applied Biotechnology Research Group, School of Life Sciences, College of Liberal Arts and Sciences, University of Westminster, London, United Kingdom
| | - Barbara Lukasiewicz
- Applied Biotechnology Research Group, School of Life Sciences, College of Liberal Arts and Sciences, University of Westminster, London, United Kingdom
| | - Molly Stevens
- Department of Bioengineering, Department of Materials, IBME, Faculty of Engineering, Imperial College London, United Kingdom
| | - Serena Best
- Department of Materials Science and Metallurgy, Cambridge Centre for Medical Materials, University of Cambridge, Cambridge, United Kingdom
| | - Ruth Cameron
- Department of Materials Science and Metallurgy, Cambridge Centre for Medical Materials, University of Cambridge, Cambridge, United Kingdom
| | - Sanjay Sinha
- Wellcome-MRC Cambridge Stem Cell Institute, University of Cambridge, Cambridge, United Kingdom
| | - Sian E. Harding
- Faculty of Medicine, National Heart and Lung Institute, Imperial College London, London, United Kingdom
| | - Ipsita Roy
- Faculty of Medicine, National Heart and Lung Institute, Imperial College London, London, United Kingdom
- Department of Material Science and Engineering, Faculty of Engineering, University of Sheffield, Sheffield, United Kingdom
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10
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Malcor JD, Hunter EJ, Davidenko N, Bax DV, Cameron R, Best S, Sinha S, Farndale RW. Collagen scaffolds functionalized with triple-helical peptides support 3D HUVEC culture. Regen Biomater 2020; 7:471-482. [PMID: 33149936 PMCID: PMC7597804 DOI: 10.1093/rb/rbaa025] [Citation(s) in RCA: 9] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/11/2020] [Revised: 05/10/2020] [Accepted: 05/15/2020] [Indexed: 02/07/2023] Open
Abstract
Porous biomaterials which provide a structural and biological support for cells have immense potential in tissue engineering and cell-based therapies for tissue repair. Collagen biomaterials that can host endothelial cells represent promising tools for the vascularization of engineered tissues. Three-dimensional collagen scaffolds possessing controlled architecture and mechanical stiffness are obtained through freeze–drying of collagen suspensions, followed by chemical cross-linking which maintains their stability. However, cross-linking scaffolds renders their biological activity suboptimal for many cell types, including human umbilical vein endothelial cells (HUVECs), by inhibiting cell–collagen interactions. Here, we have improved crucial HUVEC interactions with such cross-linked collagen biomaterials by covalently coupling combinations of triple-helical peptides (THPs). These are ligands for collagen-binding cell-surface receptors (integrins or discoidin domain receptors) or secreted proteins (SPARC and von Willebrand factor). THPs enhanced HUVEC adhesion, spreading and proliferation on 2D collagen films. THPs grafted to 3D-cross-linked collagen scaffolds promoted cell survival over seven days. This study demonstrates that THP-functionalized collagen scaffolds are promising candidates for hosting endothelial cells with potential for the production of vascularized engineered tissues in regenerative medicine applications.
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Affiliation(s)
- Jean-Daniel Malcor
- Department of Biochemistry, University of Cambridge, Cambridge CB2 1QW, UK
| | - Emma J Hunter
- Department of Biochemistry, University of Cambridge, Cambridge CB2 1QW, UK
| | - Natalia Davidenko
- Department of Materials Science and Metallurgy, University of Cambridge, Cambridge CB3 0FS, UK
| | - Daniel V Bax
- Department of Materials Science and Metallurgy, University of Cambridge, Cambridge CB3 0FS, UK
| | - Ruth Cameron
- Department of Materials Science and Metallurgy, University of Cambridge, Cambridge CB3 0FS, UK
| | - Serena Best
- Department of Materials Science and Metallurgy, University of Cambridge, Cambridge CB3 0FS, UK
| | - Sanjay Sinha
- Division of Medicine and Wellcome Trust, Medical Research Council Cambridge Stem Cell Institute, University of Cambridge, Cambridge CB2 0AW, UK
| | - Richard W Farndale
- Department of Biochemistry, University of Cambridge, Cambridge CB2 1QW, UK
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11
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Offeddu GS, Mohee L, Cameron RE. Scale and structure dependent solute diffusivity within microporous tissue engineering scaffolds. JOURNAL OF MATERIALS SCIENCE. MATERIALS IN MEDICINE 2020; 31:46. [PMID: 32367247 PMCID: PMC7198636 DOI: 10.1007/s10856-020-06381-x] [Citation(s) in RCA: 12] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 12/02/2019] [Accepted: 04/13/2020] [Indexed: 05/31/2023]
Abstract
Diffusion of nutrients to cells cultured within three-dimensional scaffolds is fundamental for cell survival during development of the tissue construct, when no vasculature is present to aid transport. Significant efforts have been made to characterize the effect of structure on solute diffusivity in nanoporous hydrogels, yet a similar thorough characterization has not been attempted for microporous scaffolds. Here, we make use of freeze-dried collagen scaffolds, possessing pore sizes in the range 150-250 μm and isotropic or aligned morphology, to study the diffusivity of fluorescent dextran molecules. Fluorescence recovery after photobleaching is used to measure the self diffusivity of the solutes within single pores, while Fickian diffusion over scales larger than the pore size is studied by assessing the solute concentration profile within the materials over time. We show that, not only do the morphological parameters of the scaffolds significantly affect the diffusivity of the solutes, but also that the assessment of such diffusivity depends on the length scale of diffusion of the molecules under investigation, with the resulting diffusion coefficients being differently affected by the scaffold structure. The results provided can guide the design of scaffolds with tailored diffusivity and nutrient concentration profiles.
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Affiliation(s)
- Giovanni S Offeddu
- Cambridge Centre for Medical Materials, Department of Materials Science and Metallurgy, University of Cambridge, 27 Charles Babbage Rd, Cambridge, CB3 0FS, UK
| | - Lakshana Mohee
- Cambridge Centre for Medical Materials, Department of Materials Science and Metallurgy, University of Cambridge, 27 Charles Babbage Rd, Cambridge, CB3 0FS, UK
| | - Ruth E Cameron
- Cambridge Centre for Medical Materials, Department of Materials Science and Metallurgy, University of Cambridge, 27 Charles Babbage Rd, Cambridge, CB3 0FS, UK.
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12
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Park S, Lim S, Siriviriyakul P, Jeon JS. Three-dimensional pore network characterization of reconstructed extracellular matrix. Phys Rev E 2020; 101:052414. [PMID: 32575345 DOI: 10.1103/physreve.101.052414] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/25/2019] [Accepted: 04/26/2020] [Indexed: 06/11/2023]
Abstract
The extracellular matrix (ECM) has a fiber network that provides physical scaffolds to cells and plays important roles by regulating cellular functions. Some previous works characterized the mechanical and geometrical properties of the ECM fiber network using reconstituted collagen-I. However, the characterization of the porous structure of reconstituted collagen-I has been limited to the pore diameter measurement, and pore network extraction has not been applied to reconstituted collagen-I despite the importance of pore interconnectivity. Here, we aim to show the importance of characterizing the pore network of reconstituted collagen-I by comparing the pore networks of structures that have different fiber alignments. We show that the fiber alignment significantly changes the pore throat area but not the pore diameter. Also, we demonstrate that larger pore throats are directed in the direction of the fiber alignment, which may help in understanding the enhanced cell migration when fibers are aligned.
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Affiliation(s)
- Seongjin Park
- Mechanical Engineering, Korea Advanced Institute of Science and Technology, Daejeon 34141, Korea
| | - Seongjin Lim
- Mechanical Engineering, Korea Advanced Institute of Science and Technology, Daejeon 34141, Korea
| | - Pan Siriviriyakul
- Mechanical Engineering, Korea Advanced Institute of Science and Technology, Daejeon 34141, Korea
| | - Jessie S Jeon
- Mechanical Engineering, Korea Advanced Institute of Science and Technology, Daejeon 34141, Korea
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13
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Nair M, Shepherd JH, Best SM, Cameron RE. MicroCT analysis of connectivity in porous structures: optimizing data acquisition and analytical methods in the context of tissue engineering. J R Soc Interface 2020; 17:20190833. [PMID: 32316883 PMCID: PMC7211477 DOI: 10.1098/rsif.2019.0833] [Citation(s) in RCA: 8] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/21/2023] Open
Abstract
Micro-computed X-ray tomography (MicroCT) is one of the most powerful techniques available for the three-dimensional characterization of complex multi-phase or porous microarchitectures. The imaging and analysis of porous networks are of particular interest in tissue engineering due to the ability to predict various large-scale cellular phenomena through the micro-scale characterization of the structure. However, optimizing the parameters for MicroCT data capture and analyses requires a careful balance of feature resolution and computational constraints while ensuring that a structurally representative section is imaged and analysed. In this work, artificial datasets were used to evaluate the validity of current analytical methods by considering the effect of noise and pixel size arising from the data capture, and intrinsic structural anisotropy and heterogeneity. A novel ‘segmented percolation method’ was developed to exclude the effect of anomalous, non-representative features within the datasets, allowing for scale-invariant structural parameters to be obtained consistently and without manual intervention for the first time. Finally, an in-depth assessment of the imaging and analytical procedures are presented by considering percolation events such as micro-particle filtration and cell sieving within the context of tissue engineering. Along with the novel guidelines established for general pixel size selection for MicroCT, we also report our determination of 3 μm as the definitive pixel size for use in analysing connectivity for tissue engineering applications.
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Affiliation(s)
- Malavika Nair
- Cambridge Centre for Medical Materials, Department of Materials Science and Metallurgy, University of Cambridge, 27 Charles Babbage Road, Cambridge CB3 0FS, UK
| | - Jennifer H Shepherd
- School of Engineering, University of Leicester, University Road, Leicester LE1 7RH, UK
| | - Serena M Best
- Cambridge Centre for Medical Materials, Department of Materials Science and Metallurgy, University of Cambridge, 27 Charles Babbage Road, Cambridge CB3 0FS, UK
| | - Ruth E Cameron
- Cambridge Centre for Medical Materials, Department of Materials Science and Metallurgy, University of Cambridge, 27 Charles Babbage Road, Cambridge CB3 0FS, UK
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14
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Abbas Y, Brunel LG, Hollinshead MS, Fernando RC, Gardner L, Duncan I, Moffett A, Best S, Turco MY, Burton GJ, Cameron RE. Generation of a three-dimensional collagen scaffold-based model of the human endometrium. Interface Focus 2020; 10:20190079. [PMID: 32194932 PMCID: PMC7061944 DOI: 10.1098/rsfs.2019.0079] [Citation(s) in RCA: 64] [Impact Index Per Article: 16.0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Accepted: 11/13/2019] [Indexed: 12/13/2022] Open
Abstract
The endometrium is the secretory lining of the uterus that undergoes dynamic changes throughout the menstrual cycle in preparation for implantation and a pregnancy. Recently, endometrial organoids (EO) were established to study the glandular epithelium. We have built upon this advance and developed a multi-cellular model containing both endometrial stromal and epithelial cells. We use porous collagen scaffolds produced with controlled lyophilization to direct cellular organization, integrating organoids with primary isolates of stromal cells. The internal pore structure of the scaffold was optimized for stromal cell culture in a systematic study, finding an optimal average pore size of 101 µm. EO seeded organize to form a luminal-like epithelial layer, on the surface of the scaffold. The cells polarize with their apical surface carrying microvilli and cilia that face the pore cavities and their basal surface attaching to the scaffold with the formation of extracellular matrix proteins. Both cell types are hormone responsive on the scaffold, with hormone stimulation resulting in epithelial differentiation and stromal decidualization.
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Affiliation(s)
- Yassen Abbas
- Department of Pathology, University of Cambridge, Cambridge CB2 1QP, UK
- Centre for Trophoblast Research (CTR), University of Cambridge, Cambridge CB2 3EG, UK
- Department of Physiology, Development and Neuroscience, University of Cambridge, Cambridge CB2 3EG, UK
| | - Lucia G. Brunel
- Department of Materials Science and Metallurgy, University of Cambridge, 27 Charles Babbage Road, Cambridge CB3 0FS, UK
| | | | - Ridma C. Fernando
- Department of Pathology, University of Cambridge, Cambridge CB2 1QP, UK
- Centre for Trophoblast Research (CTR), University of Cambridge, Cambridge CB2 3EG, UK
- Department of Physiology, Development and Neuroscience, University of Cambridge, Cambridge CB2 3EG, UK
| | - Lucy Gardner
- Department of Pathology, University of Cambridge, Cambridge CB2 1QP, UK
- Centre for Trophoblast Research (CTR), University of Cambridge, Cambridge CB2 3EG, UK
- Department of Physiology, Development and Neuroscience, University of Cambridge, Cambridge CB2 3EG, UK
| | - Imogen Duncan
- Department of Pathology, University of Cambridge, Cambridge CB2 1QP, UK
- Centre for Trophoblast Research (CTR), University of Cambridge, Cambridge CB2 3EG, UK
| | - Ashley Moffett
- Department of Pathology, University of Cambridge, Cambridge CB2 1QP, UK
- Centre for Trophoblast Research (CTR), University of Cambridge, Cambridge CB2 3EG, UK
| | - Serena Best
- Department of Materials Science and Metallurgy, University of Cambridge, 27 Charles Babbage Road, Cambridge CB3 0FS, UK
| | - Margherita Y. Turco
- Department of Pathology, University of Cambridge, Cambridge CB2 1QP, UK
- Centre for Trophoblast Research (CTR), University of Cambridge, Cambridge CB2 3EG, UK
- Department of Physiology, Development and Neuroscience, University of Cambridge, Cambridge CB2 3EG, UK
| | - Graham J. Burton
- Centre for Trophoblast Research (CTR), University of Cambridge, Cambridge CB2 3EG, UK
- Department of Physiology, Development and Neuroscience, University of Cambridge, Cambridge CB2 3EG, 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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15
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Palmroth A, Pitkänen S, Hannula M, Paakinaho K, Hyttinen J, Miettinen S, Kellomäki M. Evaluation of scaffold microstructure and comparison of cell seeding methods using micro-computed tomography-based tools. J R Soc Interface 2020; 17:20200102. [PMID: 32228403 PMCID: PMC7211473 DOI: 10.1098/rsif.2020.0102] [Citation(s) in RCA: 8] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/11/2020] [Accepted: 03/16/2020] [Indexed: 12/24/2022] Open
Abstract
Micro-computed tomography (micro-CT) provides a means to analyse and model three-dimensional (3D) tissue engineering scaffolds. This study proposes a set of micro-CT-based tools firstly for evaluating the microstructure of scaffolds and secondly for comparing different cell seeding methods. The pore size, porosity and pore interconnectivity of supercritical CO2 processed poly(l-lactide-co-ɛ-caprolactone) (PLCL) and PLCL/β-tricalcium phosphate scaffolds were analysed using computational micro-CT models. The models were supplemented with an experimental method, where iron-labelled microspheres were seeded into the scaffolds and micro-CT imaged to assess their infiltration into the scaffolds. After examining the scaffold architecture, human adipose-derived stem cells (hASCs) were seeded into the scaffolds using five different cell seeding methods. Cell viability, number and 3D distribution were evaluated. The distribution of the cells was analysed using micro-CT by labelling the hASCs with ultrasmall paramagnetic iron oxide nanoparticles. Among the tested seeding methods, a forced fluid flow-based technique resulted in an enhanced cell infiltration throughout the scaffolds compared with static seeding. The current study provides an excellent set of tools for the development of scaffolds and for the design of 3D cell culture experiments.
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Affiliation(s)
- Aleksi Palmroth
- Biomaterials and Tissue Engineering Group, BioMediTech, Faculty of Medicine and Health Technology, Tampere University, Korkeakoulunkatu 3, 33720 Tampere, Finland
| | - Sanna Pitkänen
- Adult Stem Cell Group, Tampere University, Tampere, Finland
- Research, Development and Innovation Centre, Tampere University Hospital, Tampere, Finland
| | - Markus Hannula
- Computational Biophysics and Imaging Group, BioMediTech, Faculty of Medicine and Health Technology, Tampere University, Tampere, Finland
| | - Kaarlo Paakinaho
- Adult Stem Cell Group, Tampere University, Tampere, Finland
- Orton Orthopaedic Hospital, Helsinki, Finland
| | - Jari Hyttinen
- Computational Biophysics and Imaging Group, BioMediTech, Faculty of Medicine and Health Technology, Tampere University, Tampere, Finland
| | - Susanna Miettinen
- Adult Stem Cell Group, Tampere University, Tampere, Finland
- Research, Development and Innovation Centre, Tampere University Hospital, Tampere, Finland
| | - Minna Kellomäki
- Biomaterials and Tissue Engineering Group, BioMediTech, Faculty of Medicine and Health Technology, Tampere University, Korkeakoulunkatu 3, 33720 Tampere, Finland
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16
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Tissue Response to a Porous Collagen Matrix Used for Soft Tissue Augmentation. MATERIALS 2019; 12:ma12223721. [PMID: 31718004 PMCID: PMC6888327 DOI: 10.3390/ma12223721] [Citation(s) in RCA: 22] [Impact Index Per Article: 4.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 10/11/2019] [Revised: 10/29/2019] [Accepted: 11/04/2019] [Indexed: 01/05/2023]
Abstract
A short inflammatory phase and fast ingrowth of blood vessels and mesenchymal cells are essential for tissue integration of a biomaterial. Macrophages play a key role in this process. We investigated invasion of macrophages, blood vessels, and proliferating cells into a highly porous and volume-stable collagen matrix (VCMX) used for soft tissue augmentation around teeth and dental implants. The biomaterial was implanted in submucosal pouches in the canine maxilla, and the tissue response was analyzed at six different time points. Immunohistochemistry was done for proliferating cells (PCNA), macrophages (MAC387), multinucleated giant cells (CD86), and blood vessels (TGM2). Blood rapidly filled the VCMX pores. During the first week, MAC387+ cells populated the VCMX pores, blood vessels and PCNA+ cells invaded the VCMX, and CD86+ scattered cells were observed. At 15 days, MAC387+ cells were scanty, blood vessels had completely invaded the VCMX, the number of proliferating cells peaked, and fibroblasts appeared. At 30 days, MAC387+ were absent, the numbers of proliferating and CD86+ cells had declined, while blood vessel and fibroblast numbers were high. At 90 days, residual VCMX was well-integrated in soft connective tissue. In conclusion, the VCMX elicited a short inflammatory phase followed by rapid tissue integration.
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17
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Hettich G, Schierjott RA, Epple M, Gbureck U, Heinemann S, Mozaffari-Jovein H, Grupp TM. Calcium Phosphate Bone Graft Substitutes with High Mechanical Load Capacity and High Degree of Interconnecting Porosity. MATERIALS (BASEL, SWITZERLAND) 2019; 12:E3471. [PMID: 31652704 PMCID: PMC6862383 DOI: 10.3390/ma12213471] [Citation(s) in RCA: 11] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 09/23/2019] [Revised: 10/17/2019] [Accepted: 10/18/2019] [Indexed: 01/07/2023]
Abstract
Bone graft substitutes in orthopedic applications have to fulfill various demanding requirements. Most calcium phosphate (CaP) bone graft substitutes are highly porous to achieve bone regeneration, but typically lack mechanical stability. This study presents a novel approach, in which a scaffold structure with appropriate properties for bone regeneration emerges from the space between specifically shaped granules. The granule types were tetrapods (TEPO) and pyramids (PYRA), which were compared to porous CaP granules (CALC) and morselized bone chips (BC). Bulk materials of the granules were mechanically loaded with a peak pressure of 4 MP; i.e., comparable to the load occurring behind an acetabular cup. Mechanical loading reduced the volume of CALC and BC considerably (89% and 85%, respectively), indicating a collapse of the macroporous structure. Volumes of TEPO and PYRA remained almost constant (94% and 98%, respectively). After loading, the porosity was highest for BC (46%), lowest for CALC (25%) and comparable for TEPO and PYRA (37%). The pore spaces of TEPO and PYRA were highly interconnected in a way that a virtual object with a diameter of 150 µm could access 34% of the TEPO volume and 36% of the PYRA volume. This study shows that a bulk of dense CaP granules in form of tetrapods and pyramids can create a scaffold structure with load capacities suitable for the regeneration of an acetabular bone defect.
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Affiliation(s)
- Georg Hettich
- Aesculap AG, Research & Development, Am Aesculap-Platz, 78532 Tuttlingen, Germany.
| | - Ronja A Schierjott
- Aesculap AG, Research & Development, Am Aesculap-Platz, 78532 Tuttlingen, Germany.
- Department of Orthopaedics, Physical Medicine and Rehabilitation, Department of the Ludwig-Maximilians-Universität München Marchioninistrasse 15, 81377 Munich, Germany.
| | - Matthias Epple
- Inorganic Chemistry and Center for Nanointegration Duisburg-Essen (CeNIDE), University of Duisburg-Essen, Universitaetsstr. 5-7, 45117 Essen, Germany.
| | - Uwe Gbureck
- Department for Functional Materials in Medicine and Dentistry, University of Wuerzburg, Pleicherwall 2, 97070 Wuerzburg, Germany.
| | - Sascha Heinemann
- INNOTERE biomaterial, Meissner Str. 191, 01445 Radebeul, Germany.
| | - Hadi Mozaffari-Jovein
- Institute of Materials Science and Engineering Tuttlingen (IWAT), Furtwangen University, Kronenstraße 16, 78532 Tuttlingen, Germany.
| | - Thomas M Grupp
- Aesculap AG, Research & Development, Am Aesculap-Platz, 78532 Tuttlingen, Germany.
- Department of Orthopaedics, Physical Medicine and Rehabilitation, Department of the Ludwig-Maximilians-Universität München Marchioninistrasse 15, 81377 Munich, Germany.
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18
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Tanase CE, Qutachi O, White LJ, Shakesheff KM, McCaskie AW, Best SM, Cameron RE. Targeted protein delivery: carbodiimide crosslinking influences protein release from microparticles incorporated within collagen scaffolds. Regen Biomater 2019; 6:279-287. [PMID: 31616565 PMCID: PMC6783698 DOI: 10.1093/rb/rbz015] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/21/2019] [Accepted: 03/11/2019] [Indexed: 12/17/2022] Open
Abstract
Tissue engineering response may be tailored via controlled, sustained release of active agents from protein-loaded degradable microparticles incorporated directly within three-dimensional (3D) ice-templated collagen scaffolds. However, the effects of covalent crosslinking during scaffold preparation on the availability and release of protein from the incorporated microparticles have not been explored. Here, we load 3D ice-templated collagen scaffolds with controlled additions of poly-(DL-lactide-co-glycolide) microparticles. We probe the effects of subsequent N-(3-dimethylaminopropyl)-N'-ethylcarbodiimide hydrochloride crosslinking on protein release, using microparticles with different internal protein distributions. Fluorescein isothiocyanate labelled bovine serum albumin is used as a model protein drug. The scaffolds display a homogeneous microparticle distribution, and a reduction in pore size and percolation diameter with increased microparticle addition, although these values did not fall below those reported as necessary for cell invasion. The protein distribution within the microparticles, near the surface or more deeply located within the microparticles, was important in determining the release profile and effect of crosslinking, as the surface was affected by the carbodiimide crosslinking reaction applied to the scaffold. Crosslinking of microparticles with a high proportion of protein at the surface caused both a reduction and delay in protein release. Protein located within the bulk of the microparticles, was protected from the crosslinking reaction and no delay in the overall release profile was seen.
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Affiliation(s)
- Constantin Edi Tanase
- Department of Materials Science and Metallurgy, University of Cambridge, Cambridge Centre for Medical Materials, Cambridge, 27, Charles Babbage Road, UK
| | - Omar Qutachi
- Centre for Biomolecular Sciences, School of Pharmacy, University of Nottingham, University Park, Nottingham, UK
| | - Lisa J White
- Centre for Biomolecular Sciences, School of Pharmacy, University of Nottingham, University Park, Nottingham, UK
| | - Kevin M Shakesheff
- Centre for Biomolecular Sciences, School of Pharmacy, University of Nottingham, University Park, Nottingham, UK
| | - Andrew W McCaskie
- Division of Trauma & Orthopaedic Surgery, Department of Surgery, University of Cambridge, Addenbrooke's Hospital, Hills Road, Cambridge, UK
| | - Serena M Best
- Department of Materials Science and Metallurgy, University of Cambridge, Cambridge Centre for Medical Materials, Cambridge, 27, Charles Babbage Road, UK
| | - Ruth E Cameron
- Department of Materials Science and Metallurgy, University of Cambridge, Cambridge Centre for Medical Materials, Cambridge, 27, Charles Babbage Road, UK
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19
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Gariboldi MI, Butler R, Best SM, Cameron RE. Engineering vasculature: Architectural effects on microcapillary-like structure self-assembly. PLoS One 2019; 14:e0210390. [PMID: 30620757 PMCID: PMC6324810 DOI: 10.1371/journal.pone.0210390] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/19/2018] [Accepted: 12/21/2018] [Indexed: 01/24/2023] Open
Abstract
One of the greatest obstacles to clinical translation of bone tissue engineering is the inability to effectively and efficiently vascularize scaffolds. The goal of this work was to explore systematically whether architecture, at a scale of hundreds of microns, can be used to direct the growth of microcapillary-like structures into the core of scaffolds. Biphasic bioceramic patterned architectures were produced using silicone molds of 3D printed parts. Grooves and ridges were designed to have widths of 330 μm and 660 μm, with periodicities respectively of 1240 μm and 630 μm. Groove depth was varied between 150 μm and 585 μm. Co-cultures of human dermal microvascular endothelial cells (HDMECs) and human osteoblasts (hOBs) were used to grow microcapillary-like structures on substrates. Bioceramic architecture was found to significantly affect microcapillary-like structure location and orientation. Microcapillary-like structures were found to form predominantly in grooves or between convexities. For all patterned samples, the CD31 (endothelial cell marker) signal was at least 2.5 times higher along grooves versus perpendicular to grooves. In addition, the average signal was at least two times higher within grooves than outside grooves for all samples. Grooves with a width of 330 μm and a depth of 300 μm resulted in the formation of individual, highly aligned microcapillary-like structures with lengths around 5 mm. Extensive literature has focused on the role of nano- and micro-topography (on the scale below tens of microns) on cellular response. However, the idea that architecture at a scale much larger than a cell could be used to modulate angiogenesis has not been systematically investigated. This work shows the crucial influence of architecture on microcapillary-like structure self-assembly at the scale of hundreds of microns. Elucidating the precise correspondence between architecture and microcapillary-like structure organization will ultimately allow the engineering of microvasculature by tuning local scaffold design to achieve desirable microvessel properties.
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Affiliation(s)
- Maria Isabella Gariboldi
- Cambridge Centre for Medical Materials, Department of Materials Science and Metallurgy, University of Cambridge, Cambridge, United Kingdom
| | - Richard Butler
- Imaging Facility, Gurdon Institute, University of Cambridge, Cambridge, United Kingdom
| | - Serena M. Best
- Cambridge Centre for Medical Materials, Department of Materials Science and Metallurgy, University of Cambridge, Cambridge, United Kingdom
| | - Ruth E. Cameron
- Cambridge Centre for Medical Materials, Department of Materials Science and Metallurgy, University of Cambridge, Cambridge, United Kingdom
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20
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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: 24] [Impact Index Per Article: 4.0] [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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21
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Zhang Y, Yu W, Ba Z, Cui S, Wei J, Li H. 3D-printed scaffolds of mesoporous bioglass/gliadin/polycaprolactone ternary composite for enhancement of compressive strength, degradability, cell responses and new bone tissue ingrowth. Int J Nanomedicine 2018; 13:5433-5447. [PMID: 30271139 PMCID: PMC6149932 DOI: 10.2147/ijn.s164869] [Citation(s) in RCA: 35] [Impact Index Per Article: 5.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/13/2022] Open
Abstract
BACKGROUND Due to the increasing number of patients with bone defects, bone nonunion and osteo-myelitis, tumor and congenital diseases, bone repair has become an urgent problem to be solved. METHODS In this study, the 3D-printed scaffolds of ternary composites containing mesoporous bioglass fibers of magnesium calcium silicate (mMCS), gliadin (GA) and polycaprolactone (PCL) were fabricated using a 3D Bioprinter. RESULTS The compressive strength and in vitro degradability of the mMCS/GA/PCL composites (MGPC) scaffolds were improved with the increase of mMCS content. In addition, the attachment and proliferation of MC3T3-E1 cells on the scaffolds were significantly promoted with the increase of mMCS content. Moreover, the cells with normal phenotype attached and spread well on the scaffolds surfaces, indicating good cytocompatibility. The scaffolds were implanted into the femur defects of rabbits, and the results demonstrated that the scaffold containing mMCS stimulated new bone formation and ingrowth into the scaffolds through scaffolds degradation in vivo. Moreover, the expression of type I collagen into scaffolds was enhanced with the increase of mMCS content. CONCLUSION The 3D-printed MGPC scaffold with controllable architecture, good biocompatibility, high compressive strength, proper degradability and excellent in vivo osteogenesis has great potential for bone regeneration.
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Affiliation(s)
- Yiqun Zhang
- Department of Hand Surgery, China-Japan Union Hospital, Jilin University, Changchun 130033, China,
| | - Wei Yu
- Department of Hand Surgery, China-Japan Union Hospital, Jilin University, Changchun 130033, China,
| | - Zhaoyu Ba
- Department of Spinal Surgery, Shanghai East Hospital, Tongji University School of Medicine, Shanghai 200120, China,
| | - Shusen Cui
- Department of Hand Surgery, China-Japan Union Hospital, Jilin University, Changchun 130033, China,
| | - Jie Wei
- Key Laboratory for Ultrafine Materials of Ministry of Education, East China University of Science and Technology, Shanghai 200237, China
| | - Hong Li
- College of Physical Science and Technology, Sichuan University, Chengdu 610041, China
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22
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Offeddu GS, Tanase CE, Toumpaniari S, Oyen ML, Cameron RE. Stiffening by Osmotic Swelling Constraint in Cartilage-Like Cell Culture Scaffolds. Macromol Biosci 2018; 18:e1800247. [PMID: 30187996 DOI: 10.1002/mabi.201800247] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/02/2018] [Indexed: 12/27/2022]
Abstract
Cartilage wounds result in chronic pain and degradation of the quality of life for millions of people. A synthetic cellular scaffold able to heal the damage by substituting the natural tissue is of great potential value. Here, it is shown for the first time that the unique interplay between the molecular components of cartilage can be reproduced in composite materials made of a polyelectrolyte hydrogel embedding a collagen scaffold. These composites possess a mechanical response determined by osmotic and electrostatic effects, comparable to articular cartilage in terms of elastic modulus, time-dependent response, and permeability to interstitial fluid flow. Made entirely from biocompatible materials, the cartilage-like composite materials developed permit 3D culture of chondrocyte-like cells through their microporosity. The biomimetic materials presented here constitute an entirely new class of osmotically stiffened composites, which may find use outside of biomedical applications.
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Affiliation(s)
- Giovanni S Offeddu
- Cambridge Centre for Medical Materials, Department of Materials Science and Metallurgy, University of Cambridge, 27 Charles Babbage Rd, Cambridge, CB3 0FS, UK.,The Nanoscience Centre, Department of Engineering, University of Cambridge, 11 JJ Thomson Ave, Cambridge, CB3 0FF, UK
| | - Constantin E Tanase
- Cambridge Centre for Medical Materials, Department of Materials Science and Metallurgy, University of Cambridge, 27 Charles Babbage Rd, Cambridge, CB3 0FS, UK
| | - Sotiria Toumpaniari
- Cambridge Centre for Medical Materials, Department of Materials Science and Metallurgy, University of Cambridge, 27 Charles Babbage Rd, Cambridge, CB3 0FS, UK
| | - Michelle L Oyen
- The Nanoscience Centre, Department of Engineering, University of Cambridge, 11 JJ Thomson Ave, Cambridge, CB3 0FF, UK
| | - Ruth E Cameron
- Cambridge Centre for Medical Materials, Department of Materials Science and Metallurgy, University of Cambridge, 27 Charles Babbage Rd, Cambridge, CB3 0FS, UK
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23
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Shepherd JH, Howard D, Waller AK, Foster HR, Mueller A, Moreau T, Evans AL, Arumugam M, Bouët Chalon G, Vriend E, Davidenko N, Ghevaert C, Best SM, Cameron RE. Structurally graduated collagen scaffolds applied to the ex vivo generation of platelets from human pluripotent stem cell-derived megakaryocytes: Enhancing production and purity. Biomaterials 2018; 182:135-144. [PMID: 30118981 DOI: 10.1016/j.biomaterials.2018.08.019] [Citation(s) in RCA: 37] [Impact Index Per Article: 6.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/23/2018] [Revised: 08/03/2018] [Accepted: 08/06/2018] [Indexed: 01/05/2023]
Abstract
Platelet transfusions are a key treatment option for a range of life threatening conditions including cancer, chemotherapy and surgery. Efficient ex vivo systems to generate donor independent platelets in clinically relevant numbers could provide a useful substitute. Large quantities of megakaryocytes (MKs) can be produced from human pluripotent stem cells, but in 2D culture the ratio of platelets harvested from MK cells has been limited and restricts production rate. The development of biomaterial cell supports that replicate vital hematopoietic micro-environment cues are one strategy that may increase in vitro platelet production rates from iPS derived Megakaryocyte cells. In this paper, we present the results obtained generating, simulating and using a novel structurally-graded collagen scaffold within a flow bioreactor system seeded with programmed stem cells. Theoretical analysis of porosity using micro-computed tomography analysis and synthetic micro-particle filtration provided a predictive tool to tailor cell distribution throughout the material. When used with MK programmed stem cells the graded scaffolds influenced cell location while maintaining the ability to continuously release metabolically active CD41 + CD42 + functional platelets. This scaffold design and novel fabrication technique offers a significant advance in understanding the influence of scaffold architectures on cell seeding, retention and platelet production.
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Affiliation(s)
- Jennifer H Shepherd
- Cambridge Centre for Medical Materials, Department of Materials Science and Metallurgy, 27 Charles Babbage Road, Cambridge CB3 0FS, UK.
| | - Daniel Howard
- Department of Haematology, University of Cambridge, National Health Blood Service Centre, Long Road, Cambridge CB2 0PT, UK
| | - Amie K Waller
- Department of Haematology, University of Cambridge, National Health Blood Service Centre, Long Road, Cambridge CB2 0PT, UK
| | - Holly Rebecca Foster
- Department of Haematology, University of Cambridge, National Health Blood Service Centre, Long Road, Cambridge CB2 0PT, UK
| | - Annett Mueller
- Department of Haematology, University of Cambridge, National Health Blood Service Centre, Long Road, Cambridge CB2 0PT, UK
| | - Thomas Moreau
- Department of Haematology, University of Cambridge, National Health Blood Service Centre, Long Road, Cambridge CB2 0PT, UK
| | - Amanda L Evans
- Department of Haematology, University of Cambridge, National Health Blood Service Centre, Long Road, Cambridge CB2 0PT, UK
| | - Meera Arumugam
- Department of Haematology, University of Cambridge, National Health Blood Service Centre, Long Road, Cambridge CB2 0PT, UK
| | - Guénaëlle Bouët Chalon
- Department of Haematology, University of Cambridge, National Health Blood Service Centre, Long Road, Cambridge CB2 0PT, UK
| | - Eleonora Vriend
- Cambridge Centre for Medical Materials, Department of Materials Science and Metallurgy, 27 Charles Babbage Road, Cambridge CB3 0FS, UK
| | - Natalia Davidenko
- Cambridge Centre for Medical Materials, Department of Materials Science and Metallurgy, 27 Charles Babbage Road, Cambridge CB3 0FS, UK
| | - Cedric Ghevaert
- Department of Haematology, University of Cambridge, National Health Blood Service Centre, Long Road, Cambridge CB2 0PT, UK.
| | - Serena M Best
- Cambridge Centre for Medical Materials, Department of Materials Science and Metallurgy, 27 Charles Babbage Road, Cambridge CB3 0FS, UK
| | - Ruth E Cameron
- Cambridge Centre for Medical Materials, Department of Materials Science and Metallurgy, 27 Charles Babbage Road, Cambridge CB3 0FS, UK
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24
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Ghayor C, Weber FE. Osteoconductive Microarchitecture of Bone Substitutes for Bone Regeneration Revisited. Front Physiol 2018; 9:960. [PMID: 30072920 PMCID: PMC6060436 DOI: 10.3389/fphys.2018.00960] [Citation(s) in RCA: 56] [Impact Index Per Article: 9.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/24/2018] [Accepted: 06/29/2018] [Indexed: 12/11/2022] Open
Abstract
In the last three decades, all efforts in bone tissue engineering were driven by the dogma that the ideal pore size in bone substitutes lies between 0.3 and 0.5 mm in diameter. Newly developed additive manufacturing methodologies for ceramics facilitate the total control over pore size, pore distribution, bottleneck size, and bottleneck distribution. Therefore, this appears to be the method of choice with which to test the aforementioned characteristics of an ideal bone substitute. To this end, we produced a library of 15 scaffolds with diverse defined pore/bottleneck dimensions and distributions, tested them in vivo in a calvarial bone defect model in rabbits, and assessed the clinically most relevant parameters: defect bridging and bony regenerated area. Our in vivo data revealed that the ideal pore/bottleneck dimension for bone substitutes is in the range of 0.7-1.2 mm, and appears therefore to be twofold to fourfold more extended than previously thought. Pore/bottleneck dimensions of 1.5 and 1.7 mm perform significantly worse and appear unsuitable in bone substitutes. Thus, our results set the ideal range of pore/bottleneck dimensions and are likely to have a significant impact on the microarchitectural design of future bone substitutes for use in orthopedic, trauma, cranio-maxillofacial and oral surgery.
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Affiliation(s)
- Chafik Ghayor
- Oral Biotechnology and Bioengineering, Department of Cranio-Maxillofacial and Oral Surgery, Center for Dental Medicine, University of Zurich, Zurich, Switzerland
| | - Franz E. Weber
- Oral Biotechnology and Bioengineering, Department of Cranio-Maxillofacial and Oral Surgery, Center for Dental Medicine, University of Zurich, Zurich, Switzerland
- Zurich Center for Integrative Human Physiology, University of Zurich, Zurich, Switzerland
- Center for Applied Biotechnology and Molecular Medicine, University of Zurich, Zurich, Switzerland
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25
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Shepherd DV, Shepherd JH, Best SM, Cameron RE. 3D imaging of cells in scaffolds: direct labelling for micro CT. JOURNAL OF MATERIALS SCIENCE. MATERIALS IN MEDICINE 2018; 29:86. [PMID: 29896644 PMCID: PMC5997119 DOI: 10.1007/s10856-018-6089-6] [Citation(s) in RCA: 12] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 02/16/2018] [Accepted: 05/14/2018] [Indexed: 05/13/2023]
Abstract
The development of in-vitro techniques to characterise the behaviour of cells in biomedical scaffolds is a rapidly developing field. However, until now it has not been possible to visualise, directly in 3D, the extent of cell migration using a desktop X-ray microCT. This paper describes a new technique based on cell labelling with a radio opacifier (barium sulphate), which permits cell tracking without the need for destructive sample preparation. The ability to track cells is highlighted via a comparison of cell migration through demonstrator lyophilised collagen scaffolds with contrasting pore size and interconnectivity. The results demonstrate the ease with which the technique can be used to characterise the effects of scaffold architecture on cell infiltration.
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Affiliation(s)
- David V Shepherd
- Department of Materials Science and Metallurgy, University of Cambridge, 27 Charles Babbage Road, Cambridge, CB3 0FS, UK.
| | - Jennifer H Shepherd
- Department of Materials Science and Metallurgy, University of Cambridge, 27 Charles Babbage Road, Cambridge, CB3 0FS, UK
| | - 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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26
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Leggett SE, Khoo AS, Wong IY. Multicellular tumor invasion and plasticity in biomimetic materials. Biomater Sci 2017; 5:1460-1479. [PMID: 28530743 PMCID: PMC5531215 DOI: 10.1039/c7bm00272f] [Citation(s) in RCA: 15] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/19/2022]
Abstract
Cancer cell invasion through the extracellular matrix is associated with metastatic spread and therapeutic resistance. In carcinomas, the detachment and dissemination of individual cells has been associated with an epithelial-mesenchymal transition, but tumors can also invade using collective, multicellular phenotypes. This malignant tumor progression is also associated with alignment and stiffening of the surrounding extracellular matrix. Historically, tumor invasion has been investigated using 2D monolayer culture, small animal models or patient histology. These assays have been complemented by the use of natural biomaterials such as reconstituted basement membrane and collagen I. More recently, engineered materials with well-defined physical, chemical and biomolecular properties have enabled more controlled microenvironments. In this review, we highlight recent developments in multicellular tumor invasion based on microfabricated structures or hydrogels. We emphasize the role of interfacial geometries, biomaterial stiffness, matrix remodeling, and co-culture models. Finally, we discuss future directions for the field, particularly integration with precision measurements of biomaterial properties and single cell heterogeneity, standardization and scale-up of these platforms, as well as integration with patient-derived samples.
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Affiliation(s)
- Susan E Leggett
- School of Engineering, Center for Biomedical Engineering, Brown University, Providence, RI 02912, USA. and Pathobiology Graduate Program, Brown University, Providence, RI 02912, USA
| | - Amanda S Khoo
- School of Engineering, Center for Biomedical Engineering, Brown University, Providence, RI 02912, USA.
| | - Ian Y Wong
- School of Engineering, Center for Biomedical Engineering, Brown University, Providence, RI 02912, USA. and Pathobiology Graduate Program, Brown University, Providence, RI 02912, USA
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27
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Pawelec KM, van Boxtel HA, Kluijtmans SG. Ice-templating of anisotropic structures with high permeability. MATERIALS SCIENCE & ENGINEERING. C, MATERIALS FOR BIOLOGICAL APPLICATIONS 2017; 76:628-636. [DOI: 10.1016/j.msec.2017.03.142] [Citation(s) in RCA: 16] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Received: 12/02/2016] [Revised: 03/10/2017] [Accepted: 03/13/2017] [Indexed: 12/01/2022]
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28
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Hamngren Blomqvist C, Gebäck T, Altskär A, Hermansson AM, Gustafsson S, Lorén N, Olsson E. Interconnectivity imaged in three dimensions: Nano-particulate silica-hydrogel structure revealed using electron tomography. Micron 2017; 100:91-105. [PMID: 28558343 DOI: 10.1016/j.micron.2017.04.012] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/11/2017] [Revised: 04/27/2017] [Accepted: 04/27/2017] [Indexed: 11/29/2022]
Abstract
We have used Electron Tomography (ET) to reveal the detailed three-dimensional structure of particulate hydrogels, a material category common in e.g. controlled release, food science, battery and biomedical applications. A full understanding of the transport properties of these gels requires knowledge about the pore structure and in particular the interconnectivity in three dimensions, since the transport takes the path of lowest resistance. The image series for ET were recorded using High-Angle Annular Dark Field Scanning Transmission Electron Microscopy (HAADF-STEM). We have studied three different particulate silica hydrogels based on primary particles with sizes ranging from 3.6nm to 22nm and with pore-size averages from 18nm to 310nm. Here, we highlight the nanostructure of the particle network and the interpenetrating pore network in two and three dimensions. The interconnectivity and distribution of width of the porous channels were obtained from the three-dimensional tomography studies while they cannot unambiguously be obtained from the two-dimensional data. Using ET, we compared the interconnectivity and accessible pore volume fraction as a function of pore size, based on direct images on the nanoscale of three different hydrogels. From this comparison, it was clear that the finest of the gels differentiated from the other two. Despite the almost identical flow properties of the two finer gels, they showed large differences concerning the accessible pore volume fraction for probes corresponding to their (two-dimensional) mean pore size. Using 2D pore size data, the finest gel provided an accessible pore volume fraction of over 90%, but for the other two gels the equivalent was only 10-20%. However, all the gels provided an accessible pore volume fraction of 30-40% when taking the third dimension into account.
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Affiliation(s)
- C Hamngren Blomqvist
- Physics, Chalmers University of Technology, S-412 96 Göteborg, Sweden; SuMo Biomaterials, VINN Excellence Centre, Chalmers University of Technology, S-412 96 Göteborg, Sweden
| | - T Gebäck
- SuMo Biomaterials, VINN Excellence Centre, Chalmers University of Technology, S-412 96 Göteborg, Sweden; Mathematical Sciences, Chalmers University of Technology, S-412 96 Göteborg, Sweden
| | - A Altskär
- SuMo Biomaterials, VINN Excellence Centre, Chalmers University of Technology, S-412 96 Göteborg, Sweden; Product Design and Perception, RISE Agrifood and Bioscience, Frans Perssons väg 6, S-402 29 Göteborg, Sweden
| | - A-M Hermansson
- SuMo Biomaterials, VINN Excellence Centre, Chalmers University of Technology, S-412 96 Göteborg, Sweden; Chemical and Biological Engineering, Chalmers University of Technology, S-412 96 Göteborg, Sweden
| | - S Gustafsson
- Physics, Chalmers University of Technology, S-412 96 Göteborg, Sweden
| | - N Lorén
- Physics, Chalmers University of Technology, S-412 96 Göteborg, Sweden; SuMo Biomaterials, VINN Excellence Centre, Chalmers University of Technology, S-412 96 Göteborg, Sweden; Product Design and Perception, RISE Agrifood and Bioscience, Frans Perssons väg 6, S-402 29 Göteborg, Sweden
| | - E Olsson
- Physics, Chalmers University of Technology, S-412 96 Göteborg, Sweden; SuMo Biomaterials, VINN Excellence Centre, Chalmers University of Technology, S-412 96 Göteborg, Sweden.
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29
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Shepherd J, Bax D, Best S, Cameron R. Collagen-Fibrinogen Lyophilised Scaffolds for Soft Tissue Regeneration. MATERIALS 2017; 10:ma10060568. [PMID: 28772927 PMCID: PMC5541296 DOI: 10.3390/ma10060568] [Citation(s) in RCA: 12] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 03/20/2017] [Revised: 05/10/2017] [Accepted: 05/11/2017] [Indexed: 01/02/2023]
Abstract
A significant body of research has considered collagen as a scaffold material for soft tissue regeneration. The main structural component of extra-cellular matrix (ECM), collagen’s advantages over synthetic polymers are numerous. However, for applications where higher stiffness and stability are required, significant cross-linking may affect bioactivity. A carbodiimide (EDC) cross-linking route consumes carboxylate groups that are key to collagen’s essential cell recognition motifs (GxOGER). Fibrinogen was considered as a promising additive as it plays a key role in the process of wound repair and contains RGD integrin binding sites which bind to a variety of cells, growth factors and cytokines. Fibrinogen’s binding sites however, also contain the same carboxylate groups as collagen. We have successfully produced highly interconnected, porous collagen-fibrinogen scaffolds using a lyophilisation technique and micro-computed tomography demonstrated minimal influence of either fibrinogen content or cross-linking concentration on the scaffold structure. The specific biological effect of fibrinogen additions into cross-linked collagen are considered by using films as a model for the struts of bulk scaffolds. By considering various additions of fibrinogen to the collagen film with increasing degrees of cross-linking, this study demonstrates a significant biological advantage with fibrinogen addition across the cross-linking concentrations typically applied to collagen-based scaffolds.
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Affiliation(s)
- Jennifer Shepherd
- Department of Materials Science and Metallurgy, University of Cambridge, Cambridge CB3 0FS, UK.
| | - Daniel Bax
- Department of Materials Science and Metallurgy, University of Cambridge, Cambridge CB3 0FS, UK.
| | - Serena Best
- Department of Materials Science and Metallurgy, University of Cambridge, Cambridge CB3 0FS, UK.
| | - Ruth Cameron
- Department of Materials Science and Metallurgy, University of Cambridge, Cambridge CB3 0FS, UK.
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30
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Bax DV, Davidenko N, Gullberg D, Hamaia SW, Farndale RW, Best SM, Cameron RE. Fundamental insight into the effect of carbodiimide crosslinking on cellular recognition of collagen-based scaffolds. Acta Biomater 2017; 49:218-234. [PMID: 27915017 DOI: 10.1016/j.actbio.2016.11.059] [Citation(s) in RCA: 90] [Impact Index Per Article: 12.9] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/23/2016] [Revised: 10/26/2016] [Accepted: 11/28/2016] [Indexed: 01/31/2023]
Abstract
Research on the development of collagen constructs is extremely important in the field of tissue engineering. Collagen scaffolds for numerous tissue engineering applications are frequently crosslinked with 1-ethyl-3-(3-dimethylaminopropyl-carbodiimide hydrochloride (EDC) in the presence of N-hydroxy-succinimide (NHS). Despite producing scaffolds with good biocompatibility and low cellular toxicity the influence of EDC/NHS crosslinking on the cell interactive properties of collagen has been overlooked. Here we have extensively studied the interaction of model cell lines with collagen I-based materials after crosslinking with different ratios of EDC in relation to the number of carboxylic acid residues on collagen. Divalent cation-dependent cell adhesion, via integrins α1β1, α2β1, α10β1 and α11β1, were sensitive to EDC crosslinking. With increasing EDC concentration, this was replaced with cation-independent adhesion. These results were replicated using purified recombinant I domains derived from integrin α1 and α2 subunits. Integrin α2β1-mediated cell spreading, apoptosis and proliferation were all heavily influenced by EDC crosslinking of collagen. Data from this rigorous study provides an exciting new insight that EDC/NHS crosslinking is utilising the same carboxylic side chain chemistry that is vital for native-like integrin-mediated cell interactions. Due to the ubiquitous usage of EDC/NHS crosslinked collagen for biomaterials fabrication this data is essential to have a full understanding in order to ensure optimized collagen-based material performance. STATEMENT OF SIGNIFICANCE Carbodiimide stabilised collagen is employed extensively for the fabrication of biologically active materials. Despite this common usage, the effect of carbodiimide crosslinking on cell-collagen interactions is unclear. Here we have found that carbodiimide crosslinking of collagen inhibits native-like, whilst increasing non-native like, cellular interactions. We propose a mechanistic model in which carbodiimide modifies the carboxylic acid groups on collagen that are essential for cell binding. As such we feel that this research provides a crucial, long awaited, insight into the bioactivity of carbodiimide crosslinked collagen. Through the ubiquitous use of collagen as a cellular substrate we feel that this is fundamental to a wide range of research activity with high impact across a broad range of disciplines.
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31
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Ai C, Cai J, Zhu J, Zhou J, Jiang J, Chen S. Effect of PET graft coated with silk fibroin via EDC/NHS crosslink on graft-bone healing in ACL reconstruction. RSC Adv 2017. [DOI: 10.1039/c7ra08636a] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/25/2022] Open
Abstract
SF coating via EDC/NHS crosslink improved the osseointegration of PET ligaments within the bone tunnel.
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Affiliation(s)
- Chengchong Ai
- Department of Sports Medicine
- Huashan Hospital
- Fudan University
- Shanghai 200040
- China
| | - Jiangyu Cai
- Department of Sports Medicine
- Huashan Hospital
- Fudan University
- Shanghai 200040
- China
| | - Jun Zhu
- National Engineering Research Center for Nanotechnology
- Shanghai 200241
- China
| | - Juan Zhou
- National Engineering Research Center for Nanotechnology
- Shanghai 200241
- China
| | - Jia Jiang
- Department of Sports Medicine
- Huashan Hospital
- Fudan University
- Shanghai 200040
- China
| | - Shiyi Chen
- Department of Sports Medicine
- Huashan Hospital
- Fudan University
- Shanghai 200040
- China
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32
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Zhang G, Stillinger FH, Torquato S. Transport, geometrical, and topological properties of stealthy disordered hyperuniform two-phase systems. J Chem Phys 2016; 145:244109. [DOI: 10.1063/1.4972862] [Citation(s) in RCA: 43] [Impact Index Per Article: 5.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/14/2022] Open
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33
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Pawelec KM, Best SM, Cameron RE. Collagen: a network for regenerative medicine. J Mater Chem B 2016; 4:6484-6496. [PMID: 27928505 PMCID: PMC5123637 DOI: 10.1039/c6tb00807k] [Citation(s) in RCA: 116] [Impact Index Per Article: 14.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/31/2016] [Accepted: 08/20/2016] [Indexed: 12/28/2022]
Abstract
The basic building block of the extra-cellular matrix in native tissue is collagen. As a structural protein, collagen has an inherent biocompatibility making it an ideal material for regenerative medicine. Cellular response, mediated by integrins, is dictated by the structure and chemistry of the collagen fibers. Fiber formation, via fibrillogenesis, can be controlled in vitro by several factors: pH, ionic strength, and collagen structure. After formation, fibers are stabilized via cross-linking. The final bioactivity of collagen scaffolds is a result of both processes. By considering each step of fabrication, scaffolds can be tailored for the specific needs of each tissue, improving their therapeutic potential.
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Affiliation(s)
- K M Pawelec
- University of Michigan , 2350 Hayward Ave , Ann Arbor , MI 48109 , USA
| | - S M Best
- Cambridge Centre for Medical Materials , University of Cambridge , Cambridge , CB3 0FS , UK .
| | - R E Cameron
- Cambridge Centre for Medical Materials , University of Cambridge , Cambridge , CB3 0FS , UK .
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34
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Davidenko N, Schuster CF, Bax DV, Farndale RW, Hamaia S, Best SM, Cameron RE. Evaluation of cell binding to collagen and gelatin: a study of the effect of 2D and 3D architecture and surface chemistry. JOURNAL OF MATERIALS SCIENCE. MATERIALS IN MEDICINE 2016; 27:148. [PMID: 27582068 PMCID: PMC5007264 DOI: 10.1007/s10856-016-5763-9] [Citation(s) in RCA: 254] [Impact Index Per Article: 31.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 06/16/2016] [Accepted: 08/03/2016] [Indexed: 05/17/2023]
Abstract
Studies of cell attachment to collagen-based materials often ignore details of the binding mechanisms-be they integrin-mediated or non-specific. In this work, we have used collagen and gelatin-based substrates with different dimensional characteristics (monolayers, thin films and porous scaffolds) in order to establish the influence of composition, crosslinking (using carbodiimide) treatment and 2D or 3D architecture on integrin-mediated cell adhesion. By varying receptor expression, using cells with collagen-binding integrins (HT1080 and C2C12 L3 cell lines, expressing α2β1, and Rugli expressing α1β1) and a parent cell line C2C12 with gelatin-binding receptors (αvβ3 and α5β1), the nature of integrin binding sites was studied in order to explain the bioactivity of different protein formulations. We have shown that alteration of the chemical identity, conformation and availability of free binding motifs (GxOGER and RGD), resulting from addition of gelatin to collagen and crosslinking, have a profound effect on the ability of cells to adhere to these formulations. Carbodiimide crosslinking ablates integrin-dependent cell activity on both two-dimensional and three-dimensional architectures while the three-dimensional scaffold structure also leads to a high level of non-specific interactions remaining on three-dimensional samples even after a rigorous washing regime. This phenomenon, promoted by crosslinking, and attributed to cell entrapment, should be considered in any assessment of the biological activity of three-dimensional substrates. Spreading data confirm the importance of integrin-mediated cell engagement for further cell activity on collagen-based compositions. In this work, we provide a simple, but effective, means of deconvoluting the effects of chemistry and dimensional characteristics of a substrate, on the cell activity of protein-derived materials, which should assist in tailoring their biological properties for specific tissue engineering applications.
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Affiliation(s)
- Natalia Davidenko
- Department of Materials Science and Metallurgy, University of Cambridge, 27 Charles Babbage Road, Cambridge, CB3 0FS, UK.
| | - Carlos F Schuster
- Department of Materials Science and Metallurgy, University of Cambridge, 27 Charles Babbage Road, Cambridge, CB3 0FS, UK
| | - Daniel V Bax
- Department of Materials Science and Metallurgy, University of Cambridge, 27 Charles Babbage Road, Cambridge, CB3 0FS, UK
| | - Richard W Farndale
- Department of Biochemistry, University of Cambridge, Downing Site, Cambridge, CB2 1QW, UK
| | - Samir Hamaia
- Department of Biochemistry, University of Cambridge, Downing Site, Cambridge, CB2 1QW, UK
| | - 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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35
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Offeddu GS, Ashworth JC, Cameron RE, Oyen ML. Structural determinants of hydration, mechanics and fluid flow in freeze-dried collagen scaffolds. Acta Biomater 2016; 41:193-203. [PMID: 27255358 DOI: 10.1016/j.actbio.2016.05.024] [Citation(s) in RCA: 38] [Impact Index Per Article: 4.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/02/2016] [Revised: 04/18/2016] [Accepted: 05/13/2016] [Indexed: 11/16/2022]
Abstract
UNLABELLED Freeze-dried scaffolds provide regeneration templates for a wide range of tissues, due to their flexibility in physical and biological properties. Control of structure is crucial for tuning such properties, and therefore scaffold functionality. However, the common approach of modeling these scaffolds as open-cell foams does not fully account for their structural complexity. Here, the validity of the open-cell model is examined across a range of physical characteristics, rigorously linking morphology to hydration and mechanical properties. Collagen scaffolds with systematic changes in relative density were characterized using Scanning Electron Microscopy, X-ray Micro-Computed Tomography and spherical indentation analyzed in a time-dependent poroelastic framework. Morphologically, all scaffolds were mid-way between the open- and closed-cell models, approaching the closed-cell model as relative density increased. Although pore size remained constant, transport pathway diameter decreased. Larger collagen fractions also produced greater volume swelling on hydration, although the change in pore diameter was constant, and relatively small at ∼6%. Mechanically, the dry and hydrated scaffold moduli varied quadratically with relative density, as expected of open-cell materials. However, the increasing pore wall closure was found to determine the time-dependent nature of the hydrated scaffold response, with a decrease in permeability producing increasingly elastic rather than viscoelastic behavior. These results demonstrate that characterizing the deviation from the open-cell model is vital to gain a full understanding of scaffold biophysical properties, and provide a template for structural studies of other freeze-dried biomaterials. STATEMENT OF SIGNIFICANCE Freeze-dried collagen sponges are three-dimensional microporous scaffolds that have been used for a number of exploratory tissue engineering applications. The characterization of the structure-properties relationships of these scaffolds is necessary to understand their biophysical behavior in vivo. In this work, the relationship between morphology and physical properties in the dry and hydrated states was investigated across a range of solid concentrations in the scaffolds. The quantitative results provided can aid the design of scaffolds with a target trade-off between mechanical properties and structural features important for their biological activity.
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Affiliation(s)
- G S Offeddu
- Nanoscience Centre, Department of Engineering, University of Cambridge, Cambridge CB3 0FF, UK; Cambridge Centre for Medical Materials, Department of Materials Science and Metallurgy, University of Cambridge, Cambridge CB3 0FF, UK
| | - J C Ashworth
- Cambridge Centre for Medical Materials, Department of Materials Science and Metallurgy, University of Cambridge, Cambridge CB3 0FF, UK
| | - R E Cameron
- Cambridge Centre for Medical Materials, Department of Materials Science and Metallurgy, University of Cambridge, Cambridge CB3 0FF, UK
| | - M L Oyen
- Nanoscience Centre, Department of Engineering, University of Cambridge, Cambridge CB3 0FF, UK.
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36
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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: 16] [Impact Index Per Article: 2.0] [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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37
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Controlling cell growth with tailorable 2D nanoholes arrays. J Colloid Interface Sci 2016; 466:150-61. [DOI: 10.1016/j.jcis.2015.12.016] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/21/2015] [Revised: 12/08/2015] [Accepted: 12/08/2015] [Indexed: 11/17/2022]
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Clarke SA, Choi SY, McKechnie M, Burke G, Dunne N, Walker G, Cunningham E, Buchanan F. Osteogenic cell response to 3-D hydroxyapatite scaffolds developed via replication of natural marine sponges. JOURNAL OF MATERIALS SCIENCE. MATERIALS IN MEDICINE 2016; 27:22. [PMID: 26704539 PMCID: PMC4690835 DOI: 10.1007/s10856-015-5630-0] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Figures] [Subscribe] [Scholar Register] [Received: 08/14/2015] [Accepted: 11/13/2015] [Indexed: 06/05/2023]
Abstract
Bone tissue engineering may provide an alternative to autograft, however scaffold optimisation is required to maximize bone ingrowth. In designing scaffolds, pore architecture is important and there is evidence that cells prefer a degree of non-uniformity. The aim of this study was to compare scaffolds derived from a natural porous marine sponge (Spongia agaricina) with unique architecture to those derived from a synthetic polyurethane foam. Hydroxyapatite scaffolds of 1 cm(3) were prepared via ceramic infiltration of a marine sponge and a polyurethane (PU) foam. Human foetal osteoblasts (hFOB) were seeded at 1 × 10(5) cells/scaffold for up to 14 days. Cytotoxicity, cell number, morphology and differentiation were investigated. PU-derived scaffolds had 84-91% porosity and 99.99% pore interconnectivity. In comparison marine sponge-derived scaffolds had 56-61% porosity and 99.9% pore interconnectivity. hFOB studies showed that a greater number of cells were found on marine sponge-derived scaffolds at than on the PU scaffold but there was no significant difference in cell differentiation. X-ray diffraction and inductively coupled plasma mass spectrometry showed that Si ions were released from the marine-derived scaffold. In summary, three dimensional porous constructs have been manufactured that support cell attachment, proliferation and differentiation but significantly more cells were seen on marine-derived scaffolds. This could be due both to the chemistry and pore architecture of the scaffolds with an additional biological stimulus from presence of Si ions. Further in vivo tests in orthotopic models are required but this marine-derived scaffold shows promise for applications in bone tissue engineering.
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Affiliation(s)
- S A Clarke
- School of Nursing and Midwifery, Queen's University of Belfast, Medical Biology Centre, 97, Lisburn Road, Belfast, BT9 7BL, UK.
| | - S Y Choi
- School of Mechanical and Aerospace Engineering, Queen's University of Belfast, Ashby Building, 121 Stranmillis Road, Belfast, BT9 5AH, UK
| | - Melanie McKechnie
- School of Biological Sciences, Queen's University of Belfast, Medical Biology Centre, 97, Lisburn Road, Belfast, BT9 7BL, UK
| | - G Burke
- Engineering Research Institute, School of Engineering, Ulster University, Jordanstown Campus, Shore Rd, Newtownabbey, BT37 0QB, UK
| | - N Dunne
- School of Mechanical and Aerospace Engineering, Queen's University of Belfast, Ashby Building, 121 Stranmillis Road, Belfast, BT9 5AH, UK
- School of Mechanical and Manufacturing Engineering, Dublin City University, Glasnevin, Dublin, 9, Ireland
| | - G Walker
- School of Mechanical and Aerospace Engineering, Queen's University of Belfast, Ashby Building, 121 Stranmillis Road, Belfast, BT9 5AH, UK
| | - E Cunningham
- School of Mechanical and Aerospace Engineering, Queen's University of Belfast, Ashby Building, 121 Stranmillis Road, Belfast, BT9 5AH, UK
| | - F Buchanan
- School of Mechanical and Aerospace Engineering, Queen's University of Belfast, Ashby Building, 121 Stranmillis Road, Belfast, BT9 5AH, UK
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John Ł, Janeta M, Rajczakowska M, Ejfler J, Łydżba D, Szafert S. Synthesis and microstructural properties of the scaffold based on a 3-(trimethoxysilyl)propyl methacrylate–POSS hybrid towards potential tissue engineering applications. RSC Adv 2016. [DOI: 10.1039/c6ra10364b] [Citation(s) in RCA: 24] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022] Open
Abstract
The biomimetic organic–inorganic scaffold with the chemical composition, structural dimensions, topography, and microstructural properties that fulfills the requirements for hard-tissue engineering was developed.
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Affiliation(s)
- Ł. John
- Faculty of Chemistry
- University of Wrocław
- 50-383 Wrocław
- Poland
| | - M. Janeta
- Faculty of Chemistry
- University of Wrocław
- 50-383 Wrocław
- Poland
| | - M. Rajczakowska
- Faculty of Civil Engineering
- Wrocław University of Science and Technology
- 50-370 Wrocław
- Poland
| | - J. Ejfler
- Faculty of Chemistry
- University of Wrocław
- 50-383 Wrocław
- Poland
| | - D. Łydżba
- Faculty of Civil Engineering
- Wrocław University of Science and Technology
- 50-370 Wrocław
- Poland
| | - S. Szafert
- Faculty of Chemistry
- University of Wrocław
- 50-383 Wrocław
- Poland
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Gariboldi MI, Best SM. Effect of Ceramic Scaffold Architectural Parameters on Biological Response. Front Bioeng Biotechnol 2015; 3:151. [PMID: 26501056 PMCID: PMC4598804 DOI: 10.3389/fbioe.2015.00151] [Citation(s) in RCA: 64] [Impact Index Per Article: 7.1] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/31/2015] [Accepted: 09/18/2015] [Indexed: 11/13/2022] Open
Abstract
Numerous studies have focused on the optimization of ceramic architectures to fulfill a variety of scaffold functional requirements and improve biological response. Conventional fabrication techniques, however, do not allow for the production of geometrically controlled, reproducible structures and often fail to allow the independent variation of individual geometric parameters. Current developments in additive manufacturing technologies suggest that 3D printing will allow a more controlled and systematic exploration of scaffold architectures. This more direct translation of design into structure requires a pipeline for design-driven optimization. A theoretical framework for systematic design and evaluation of architectural parameters on biological response is presented. Four levels of architecture are considered, namely (1) surface topography, (2) pore size and geometry, (3) porous networks, and (4) macroscopic pore arrangement, including the potential for spatially varied architectures. Studies exploring the effect of various parameters within these levels are reviewed. This framework will hopefully allow uncovering of new relationships between architecture and biological response in a more systematic way as well as inform future refinement of fabrication techniques to fulfill architectural necessities with a consideration of biological implications.
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Affiliation(s)
- Maria Isabella Gariboldi
- Department of Materials Science and Metallurgy, Cambridge Centre for Medical Materials, University of Cambridge, Cambridge, UK
| | - Serena M. Best
- Department of Materials Science and Metallurgy, Cambridge Centre for Medical Materials, University of Cambridge, Cambridge, UK
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