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Efremov YM, Zurina IM, Presniakova VS, Kosheleva NV, Butnaru DV, Svistunov AA, Rochev YA, Timashev PS. Mechanical properties of cell sheets and spheroids: the link between single cells and complex tissues. Biophys Rev 2021; 13:541-561. [PMID: 34471438 PMCID: PMC8355304 DOI: 10.1007/s12551-021-00821-w] [Citation(s) in RCA: 26] [Impact Index Per Article: 8.7] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/23/2021] [Accepted: 07/05/2021] [Indexed: 12/13/2022] Open
Abstract
Cell aggregates, including sheets and spheroids, represent a simple yet powerful model system to study both biochemical and biophysical intercellular interactions. However, it is becoming evident that, although the mechanical properties and behavior of multicellular structures share some similarities with individual cells, yet distinct differences are observed in some principal aspects. The description of mechanical phenomena at the level of multicellular model systems is a necessary step for understanding tissue mechanics and its fundamental principles in health and disease. Both cell sheets and spheroids are used in tissue engineering, and the modulation of mechanical properties of cell constructs is a promising tool for regenerative medicine. Here, we review the data on mechanical characterization of cell sheets and spheroids, focusing both on advances in the measurement techniques and current understanding of the subject. The reviewed material suggest that interplay between the ECM, intercellular junctions, and cellular contractility determines the behavior and mechanical properties of the cell aggregates.
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Affiliation(s)
- Yuri M. Efremov
- Institute for Regenerative Medicine, Sechenov First Moscow State Medical University (Sechenov University), 119991 8-2 Trubetskaya St, Moscow, Russia
- World-Class Research Center “Digital Biodesign and Personalized Healthcare”, Sechenov University, Moscow, 119991 Russia
| | - Irina M. Zurina
- Institute for Regenerative Medicine, Sechenov First Moscow State Medical University (Sechenov University), 119991 8-2 Trubetskaya St, Moscow, Russia
- FSBSI Institute of General Pathology and Pathophysiology, 125315, 8 Baltiyskaya St, Moscow, Russia
| | - Viktoria S. Presniakova
- Institute for Regenerative Medicine, Sechenov First Moscow State Medical University (Sechenov University), 119991 8-2 Trubetskaya St, Moscow, Russia
| | - Nastasia V. Kosheleva
- Institute for Regenerative Medicine, Sechenov First Moscow State Medical University (Sechenov University), 119991 8-2 Trubetskaya St, Moscow, Russia
- World-Class Research Center “Digital Biodesign and Personalized Healthcare”, Sechenov University, Moscow, 119991 Russia
- FSBSI Institute of General Pathology and Pathophysiology, 125315, 8 Baltiyskaya St, Moscow, Russia
| | - Denis V. Butnaru
- Institute for Urology and Reproductive Health, Sechenov University, Moscow, Russia
| | - Andrey A. Svistunov
- Sechenov First Moscow State Medical University (Sechenov University), 119991, 8-2 Trubetskaya St, Moscow, Russia
| | - Yury A. Rochev
- Institute for Regenerative Medicine, Sechenov First Moscow State Medical University (Sechenov University), 119991 8-2 Trubetskaya St, Moscow, Russia
- Centre for Research in Medical Devices (CÚRAM), National University of Ireland Galway, Galway, H91 W2TY, Ireland
| | - Peter S. Timashev
- Institute for Regenerative Medicine, Sechenov First Moscow State Medical University (Sechenov University), 119991 8-2 Trubetskaya St, Moscow, Russia
- World-Class Research Center “Digital Biodesign and Personalized Healthcare”, Sechenov University, Moscow, 119991 Russia
- Department of Polymers and Composites, N.N. Semenov Institute of Chemical Physics, 119991 4 Kosygin St, Moscow, Russia
- Chemistry Department, Lomonosov Moscow State University, Leninskiye Gory 1–3, Moscow, 119991 Russia
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2
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Fan H, Wang J, Feng Q, Hu Q, Zuo S, Nabaei V, Heidari H. Detection techniques of biological and chemical Hall sensors. RSC Adv 2021; 11:7257-7270. [PMID: 35423263 PMCID: PMC8695063 DOI: 10.1039/d0ra10027g] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/27/2020] [Accepted: 02/03/2021] [Indexed: 01/05/2023] Open
Abstract
Integrated magnetic Hall effect sensors have been widely used in people's daily life over the past decades, and still are gaining enormous attention from researchers to establish novel applications, especially in biochemistry and biomedical healthcare. This paper reviews, classifies, compares and concludes state-of-the-art integrated Hall magnetic sensors in terms of cost, power, area, performance and application. Current applications of the Hall sensors such as detecting magnetic nanoparticles (MNPs) labeled on biomolecule, monitoring blood pulse wave velocity, characterizing soft biological materials, controlling syringe injection rate and eye surgery by training systems, and assisting magnetic resonance imaging (MRI) will be discussed comprehensively and future applications and trends will be highlighted. This review paper will introduce Hall sensor's advantages such as simple design and technology of manufacturing, low cost, low power consumption, possibility of the miniaturizing, noninvasive and room temperature measurement, with respect to the other magnetic sensing systems and methods.
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Affiliation(s)
- Hua Fan
- State Key Laboratory of Electronic Thin Films and Integrated Devices, University of Electronic Science and Technology of China Chengdu China
| | - Jiangming Wang
- State Key Laboratory of Electronic Thin Films and Integrated Devices, University of Electronic Science and Technology of China Chengdu China
| | | | | | - Siming Zuo
- James Watt School of Engineering, University of Glasgow Glasgow G12 8QQ UK
| | - Vahid Nabaei
- James Watt School of Engineering, University of Glasgow Glasgow G12 8QQ UK
| | - Hadi Heidari
- James Watt School of Engineering, University of Glasgow Glasgow G12 8QQ UK
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3
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Kwong G, Marquez HA, Yang C, Wong JY, Kotton DN. Generation of a Purified iPSC-Derived Smooth Muscle-like Population for Cell Sheet Engineering. Stem Cell Reports 2019; 13:499-514. [PMID: 31422908 PMCID: PMC6739689 DOI: 10.1016/j.stemcr.2019.07.014] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/15/2019] [Revised: 07/18/2019] [Accepted: 07/19/2019] [Indexed: 10/31/2022] Open
Abstract
Induced pluripotent stem cells (iPSCs) provide a potential source for the derivation of smooth muscle cells (SMCs); however, current approaches are limited by the production of heterogeneous cell types and a paucity of tools or markers for tracking and purifying candidate SMCs. Here, we develop murine and human iPSC lines carrying fluorochrome reporters (Acta2hrGFP and ACTA2eGFP, respectively) that identify Acta2+/ACTA2+ cells as they emerge in vitro in real time during iPSC-directed differentiation. We find that Acta2hrGFP+ and ACTA2eGFP+ cells can be sorted to purity and are enriched in markers characteristic of an immature or synthetic SMC. We characterize the resulting GFP+ populations through global transcriptomic profiling and functional studies, including the capacity to form engineered cell sheets. We conclude that these reporter lines allow for generation of sortable, live iPSC-derived Acta2+/ACTA2+ cells highly enriched in smooth muscle lineages for basic developmental studies, tissue engineering, or future clinical regenerative applications.
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Affiliation(s)
- George Kwong
- Center for Regenerative Medicine, Boston University and Boston Medical Center, 670 Albany Street, 2(nd) Floor, Boston, MA 02118, USA; Department of Biomedical Engineering, Boston University, 44 Cummington Mall, Boston, MA 02215, USA
| | - Hector A Marquez
- Center for Regenerative Medicine, Boston University and Boston Medical Center, 670 Albany Street, 2(nd) Floor, Boston, MA 02118, USA; The Pulmonary Center and Department of Medicine, Boston University School of Medicine, 72 East Concord Street, Boston, MA 02118, USA
| | - Chian Yang
- Center for Regenerative Medicine, Boston University and Boston Medical Center, 670 Albany Street, 2(nd) Floor, Boston, MA 02118, USA; Department of Biomedical Engineering, Boston University, 44 Cummington Mall, Boston, MA 02215, USA
| | - Joyce Y Wong
- Department of Biomedical Engineering, Boston University, 44 Cummington Mall, Boston, MA 02215, USA.
| | - Darrell N Kotton
- Center for Regenerative Medicine, Boston University and Boston Medical Center, 670 Albany Street, 2(nd) Floor, Boston, MA 02118, USA; The Pulmonary Center and Department of Medicine, Boston University School of Medicine, 72 East Concord Street, Boston, MA 02118, USA.
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4
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Sorba F, Poulin A, Ischer R, Shea H, Martin-Olmos C. Integrated elastomer-based device for measuring the mechanics of adherent cell monolayers. LAB ON A CHIP 2019; 19:2138-2146. [PMID: 31115420 DOI: 10.1039/c9lc00075e] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/09/2023]
Abstract
Cells in the body collectively sustain mechanical deformations in almost all physiological functions. From the morphogenesis stage, cells' ability to sustain stress is essential for the body's well-being. Several pathologies have been associated with abnormal mechanical properties, thus suggesting the Young's modulus as a biomarker to diagnose diseases and determine their progression. Advancements in the field are quite slow because current techniques for measuring cell and tissue mechanics rely on complex and bulky measurement platforms that have low repeatability rates and limited measurement time-scales. We present the first miniaturized system that allows accurate quantification of the Young's modulus of adherent cell monolayers over a longer time (1-2 days). Our approach is based on tensile testing and optical read-out. Thanks to a thoughtful design and material choice, we are able to miniaturize tensile testing platforms into a 1 cm × 2 cm device. We provide highly repeatable Young's modulus measurements in the relevant range between 3 kPa and 300 kPa, over time and under physiological conditions, thus representing an interesting alternative to existing measurement platforms. Furthermore, the compatibility with standard biological equipment, continuous optical imaging and measurements on all types of adherent cells make this device highly versatile. Measurements on human sarcoma osteogenic (SaOS2) and Madin-Darby canine kidney cells (MDCK) are reported. The demonstrated capability to measure real-time changes in mechanical properties, such as after chemical treatment, opens the door for investigating the effects of drugs on cell mechanics.
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Affiliation(s)
- Francesca Sorba
- Swiss Center for Electronics and Microtechnology, CSEM SA, Neuchâtel, Switzerland.
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5
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Hoffmann GA, Wong JY, Smith ML. On Force and Form: Mechano-Biochemical Regulation of Extracellular Matrix. Biochemistry 2019; 58:4710-4720. [PMID: 31144496 DOI: 10.1021/acs.biochem.9b00219] [Citation(s) in RCA: 11] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/20/2022]
Abstract
The extracellular matrix is well-known for its structural role in supporting cells and tissues, and its important biochemical role in providing signals to cells has increasingly become apparent. These structural and biochemical roles are closely coupled through mechanical forces: the biochemistry of the extracellular matrix determines its mechanical properties, mechanical forces control release or display of biochemical signals from the extracellular matrix, and the mechanical properties of the matrix in turn influence the mechanical set point at which signals are sent. In this Perspective, we explain how the extracellular matrix is regulated by strain and mechanical forces. We show the impact of biochemistry and mechanical forces on in vivo assembly of extracellular matrix and illustrate how matrix can be generated in vitro using a variety of methods. We cover how the matrix can be characterized in terms of mechanics, composition, and conformation to determine its properties and to predict interactions. Finally, we explore how extracellular matrix remodeling, ligand binding, and hemostasis are regulated by mechanical forces. These recently discovered mechano-biochemical interactions have important functions in wound healing and disease progression. It is likely that mechanically altered extracellular matrix interactions are a commonly recurring theme, but due to limited tools to generate extracellular matrix fibers in vitro and lack of high-throughput methods to detect these interactions, it is hypothesized that many of these interactions have yet to be discovered.
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Affiliation(s)
- Gwendolyn A Hoffmann
- Department of Biomedical Engineering , Boston University , 44 Cummington Mall , Boston , Massachusetts 02215 , United States
| | - Joyce Y Wong
- Department of Biomedical Engineering , Boston University , 44 Cummington Mall , Boston , Massachusetts 02215 , United States
| | - Michael L Smith
- Department of Biomedical Engineering , Boston University , 44 Cummington Mall , Boston , Massachusetts 02215 , United States
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6
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Roberts EG, Rim NG, Huang W, Tarakanova A, Yeo J, Buehler MJ, Kaplan DL, Wong JY. Fabrication and Characterization of Recombinant Silk-Elastin-Like-Protein (SELP) Fiber. Macromol Biosci 2018; 18:e1800265. [PMID: 30417967 PMCID: PMC6960454 DOI: 10.1002/mabi.201800265] [Citation(s) in RCA: 22] [Impact Index Per Article: 3.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/15/2018] [Revised: 09/28/2018] [Indexed: 11/06/2022]
Abstract
Silk-elastin-like-protein polymers (SELPs) are genetically engineered recombinant protein sequences consisting of repeating units of silk-like and elastin-like blocks. By combining these entities, it is shown that both the characteristic strength of silk and the temperature-dependent responsiveness of elastin can be leveraged to create an enhanced stimuli-responsive material. It is hypothesized that SELP behavior can be influenced by varying the silk-to-elastin ratio. If the responsiveness of the material at different ratios is significantly different, this would allow for the design of materials with specific temperature-based swelling and mechanical properties. This study demonstrates that SELP fiber properties can be controlled via a temperature transition dependent on the ratio of silk-to-elastin in the material. SELP fibers are experimentally wet spun from polymers with different ratios of silk-to-elastin and conditioned in either a below or above transition temperature (T t ) water bath prior to characterization. The fibers with higher elastin content showed more stimuli-responsive behavior compared to the fibers with lower elastin content in the hot (57-60 °C) versus cold (4-7 °C) environment, both computationally and experimentally. This work builds a foundation for developing SELP materials with well-characterized mechanical properties and responsive features.
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Affiliation(s)
- Erin G Roberts
- Division of Materials Science and Engineering, Boston University, Boston, MA, 02215, USA
| | - Nae-Gyune Rim
- Department of Biomedical Engineering, Boston University, Boston, MA, 02215, USA
| | - Wenwen Huang
- Department of Biomedical Engineering, Tufts University, Medford, MA, 02155, USA
| | - Anna Tarakanova
- Department of Civil and Environmental Engineering, Massachusetts Institute of Technology, Cambridge, MA, 02139, USA
| | - Jingjie Yeo
- Department of Biomedical Engineering, Tufts University, Medford, MA, 02155, USA
- Department of Civil and Environmental Engineering, Massachusetts Institute of Technology, Cambridge, MA, 02139, USA
- Institute of High Performance Computing, A∗STAR, 1 Fusionopolis Way, Singapore, 138632, Singapore
| | - Markus J Buehler
- Department of Civil and Environmental Engineering, Massachusetts Institute of Technology, Cambridge, MA, 02139, USA
| | - David L Kaplan
- Department of Biomedical Engineering, Tufts University, Medford, MA, 02155, USA
| | - Joyce Y Wong
- Division of Materials Science and Engineering, Boston University, Boston, MA, 02215, USA
- Department of Biomedical Engineering, Boston University, Boston, MA, 02215, USA
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Roberts EG, Piekarski BL, Huang K, Emani S, Wong JY, Emani SM. Evaluation of Placental Mesenchymal Stem Cell Sheets for Myocardial Repair and Regeneration. Tissue Eng Part A 2018; 25:867-877. [PMID: 30122114 DOI: 10.1089/ten.tea.2018.0035] [Citation(s) in RCA: 10] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/10/2023] Open
Abstract
IMPACT STATEMENT This work explores placental tissue as a cell source for fabrication of tissue-engineered surgical patches for myocardial repair of congenital heart defects. This study demonstrates promising findings for the clinically driven evaluation of the cell source as defined by potential cardiac benefit, compatibility, cell source availability, and implant deliverability. It documents methods for the isolation of mesenchymal stem cells from human placental amnion and chorion tissues, characterization of these cells, and eventual cell sheet growth that can be leveraged going forward for patch fabrication. It establishes support to continue pursuing the placenta as a valuable cell source for myocardial repair.
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Affiliation(s)
- Erin G Roberts
- 1 Department of Materials Science and Engineering, Boston University, Boston, Massachusetts.,2 Department of Cardiovascular Surgery, Children's Hospital, Boston, Massachusetts
| | - Breanna L Piekarski
- 2 Department of Cardiovascular Surgery, Children's Hospital, Boston, Massachusetts
| | - Kevin Huang
- 3 Department of Biomedical Engineering, Boston University, Boston, Massachusetts
| | - Sirisha Emani
- 2 Department of Cardiovascular Surgery, Children's Hospital, Boston, Massachusetts
| | - Joyce Y Wong
- 1 Department of Materials Science and Engineering, Boston University, Boston, Massachusetts.,3 Department of Biomedical Engineering, Boston University, Boston, Massachusetts
| | - Sitaram M Emani
- 2 Department of Cardiovascular Surgery, Children's Hospital, Boston, Massachusetts
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Rim NG, Yih A, Hsi P, Wang Y, Zhang Y, Wong JY. Micropatterned cell sheets as structural building blocks for biomimetic vascular patches. Biomaterials 2018; 181:126-139. [PMID: 30081303 DOI: 10.1016/j.biomaterials.2018.07.047] [Citation(s) in RCA: 31] [Impact Index Per Article: 5.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/06/2018] [Revised: 07/21/2018] [Accepted: 07/25/2018] [Indexed: 02/07/2023]
Abstract
To successfully develop a functional tissue-engineered vascular patch, recapitulating the hierarchical structure of vessel is critical to mimic mechanical properties. Here, we use a cell sheet engineering strategy with micropatterning technique to control structural organization of bovine aortic vascular smooth muscle cell (VSMC) sheets. Actin filament staining and image analysis showed clear cellular alignment of VSMC sheets cultured on patterned substrates. Viability of harvested VSMC sheets was confirmed by Live/Dead® cell viability assay after 24 and 48 h of transfer. VSMC sheets stacked to generate bilayer VSMC patches exhibited strong inter-layer bonding as shown by lap shear test. Uniaxial tensile testing of monolayer VSMC sheets and bilayer VSMC patches displayed nonlinear, anisotropic stress-stretch response similar to the biomechanical characteristic of a native arterial wall. Collagen content and structure were characterized to determine the effects of patterning and stacking on extracellular matrix of VSMC sheets. Using finite-element modeling to simulate uniaxial tensile testing of bilayer VSMC patches, we found the stress-stretch response of bilayer patterned VSMC patches under uniaxial tension to be predicted using an anisotropic hyperelastic constitutive model. Thus, our cell sheet harvesting system combined with biomechanical modeling is a promising approach to generate building blocks for tissue-engineered vascular patches with structure and mechanical behavior mimicking native tissue.
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Affiliation(s)
- Nae Gyune Rim
- Department of Biomedical Engineering, Boston University, Boston, MA 02215, USA
| | - Alice Yih
- Department of Biomedical Engineering, Boston University, Boston, MA 02215, USA
| | - Peter Hsi
- Department of Biomedical Engineering, Boston University, Boston, MA 02215, USA
| | - Yunjie Wang
- Department of Mechanical Engineering, and Boston University, Boston, MA 02215, USA
| | - Yanhang Zhang
- Department of Biomedical Engineering, Boston University, Boston, MA 02215, USA; Department of Mechanical Engineering, and Boston University, Boston, MA 02215, USA; Division of Materials Science and Engineering, Boston University, Boston, MA 02215, USA
| | - Joyce Y Wong
- Department of Biomedical Engineering, Boston University, Boston, MA 02215, USA; Division of Materials Science and Engineering, Boston University, Boston, MA 02215, USA.
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Backman DE, LeSavage BL, Shah SB, Wong JY. A Robust Method to Generate Mechanically Anisotropic Vascular Smooth Muscle Cell Sheets for Vascular Tissue Engineering. Macromol Biosci 2017; 17:10.1002/mabi.201600434. [PMID: 28207187 PMCID: PMC5568633 DOI: 10.1002/mabi.201600434] [Citation(s) in RCA: 24] [Impact Index Per Article: 3.4] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/27/2016] [Revised: 12/22/2016] [Indexed: 12/11/2022]
Abstract
In arterial tissue engineering, mimicking native structure and mechanical properties is essential because compliance mismatch can lead to graft failure and further disease. With bottom-up tissue engineering approaches, designing tissue components with proper microscale mechanical properties is crucial to achieve the necessary macroscale properties in the final implant. This study develops a thermoresponsive cell culture platform for growing aligned vascular smooth muscle cell (VSMC) sheets by photografting N-isopropylacrylamide (NIPAAm) onto micropatterned poly(dimethysiloxane) (PDMS). The grafting process is experimentally and computationally optimized to produce PNIPAAm-PDMS substrates optimal for VSMC attachment. To allow long-term VSMC sheet culture and increase the rate of VSMC sheet formation, PNIPAAm-PDMS surfaces were further modified with 3-aminopropyltriethoxysilane yielding a robust, thermoresponsive cell culture platform for culturing VSMC sheets. VSMC cell sheets cultured on patterned thermoresponsive substrates exhibit cellular and collagen alignment in the direction of the micropattern. Mechanical characterization of patterned, single-layer VSMC sheets reveals increased stiffness in the aligned direction compared to the perpendicular direction whereas nonpatterned cell sheets exhibit no directional dependence. Structural and mechanical anisotropy of aligned, single-layer VSMC sheets makes this platform an attractive microstructural building block for engineering a vascular graft to match the in vivo mechanical properties of native arterial tissue.
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Affiliation(s)
- Daniel E Backman
- Department of Biomedical Engineering, Boston University, 44 Cummington Mall, Boston, MA, 02215, USA
| | - Bauer L LeSavage
- Department of Biomedical Engineering, Boston University, 44 Cummington Mall, Boston, MA, 02215, USA
| | - Shivem B Shah
- Department of Biomedical Engineering, Boston University, 44 Cummington Mall, Boston, MA, 02215, USA
| | - Joyce Y Wong
- Department of Biomedical Engineering, Boston University, 44 Cummington Mall, Boston, MA, 02215, USA
- Division of Materials Science and Engineering, Boston University, 15 Saint Mary's Street, Boston, MA, 02215, USA
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10
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Li D, Jacobsen MM, Rim NG, Backman D, Kaplan DL, Wong JY. Introducing biomimetic shear and ion gradients to microfluidic spinning improves silk fiber strength. Biofabrication 2017; 9:025025. [PMID: 28471354 PMCID: PMC5588659 DOI: 10.1088/1758-5090/aa711b] [Citation(s) in RCA: 13] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/12/2022]
Abstract
Silkworm silk is an attractive biopolymer for biomedical applications due to its high mechanical strength and biocompatibility; as a result, there is increasing interest in scalable devices to spin silk and recombinant silk so as to improve and customize their properties for diverse biomedical purposes (Vepari and Kaplan 2007 Prog. Polym. Sci. 32 ). While artificial spinning of regenerated silk fibroins adds tunability to properties such as degradation rate and surface functionalization, the resulting fibers do not yet approach the mechanical strength of native silkworm silk. These drawbacks reduce the applicability and attractiveness of artificial silk (Kinahan et al 2011 Biomacromolecules 12 ). Here, we used computational fluid dynamic simulations to incorporate shear in tandem with biomimetic ion gradients by coupling a modular novel glass microfluidic device to our previous co-axial flow device. Fibers spun with this combined apparatus demonstrated a significant increase in mechanical strength compared to fibers spun with the basic apparatus alone, with a three-fold increase in Young's modulus and extensibility and a twelve-fold increase in toughness. These results thus demonstrate the critical importance of ionic milieu and shear stress in spinning strong fibers from solubilized silk fibroin.
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Affiliation(s)
- David Li
- Department of Biomedical Engineering Boston University, 44 Cummington Mall, Boston, MA 02215, USA
| | - Matthew M. Jacobsen
- Department of Biomedical Engineering Boston University, 44 Cummington Mall, Boston, MA 02215, USA
| | - Nae Gyune Rim
- Department of Biomedical Engineering Boston University, 44 Cummington Mall, Boston, MA 02215, USA
| | - Daniel Backman
- Department of Biomedical Engineering Boston University, 44 Cummington Mall, Boston, MA 02215, USA
| | - David L. Kaplan
- Department of Biomedical Engineering, Tufts University, 4 Colby Street, Medford, MA 02155, USA
| | - Joyce Y. Wong
- Department of Biomedical Engineering Boston University, 44 Cummington Mall, Boston, MA 02215, USA
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11
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Silk-fibronectin protein alloy fibres support cell adhesion and viability as a high strength, matrix fibre analogue. Sci Rep 2017; 7:45653. [PMID: 28378749 PMCID: PMC5381220 DOI: 10.1038/srep45653] [Citation(s) in RCA: 21] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/03/2016] [Accepted: 03/01/2017] [Indexed: 11/08/2022] Open
Abstract
Silk is a natural polymer with broad utility in biomedical applications because it exhibits general biocompatibility and high tensile material properties. While mechanical integrity is important for most biomaterial applications, proper function and integration also requires biomaterial incorporation into complex surrounding tissues for many physiologically relevant processes such as wound healing. In this study, we spin silk fibroin into a protein alloy fibre with whole fibronectin using wet spinning approaches in order to synergize their respective strength and cell interaction capabilities. Results demonstrate that silk fibroin alone is a poor adhesive surface for fibroblasts, endothelial cells, and vascular smooth muscle cells in the absence of serum. However, significantly improved cell attachment is observed to silk-fibronectin alloy fibres without serum present while not compromising the fibres' mechanical integrity. Additionally, cell viability is improved up to six fold on alloy fibres when serum is present while migration and spreading generally increase as well. These findings demonstrate the utility of composite protein alloys as inexpensive and effective means to create durable, biologically active biomaterials.
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