1
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Wang M, Pang SW. Detecting Nanotopography Induced Changes in Cell Migration Directions Using Oxygen Sensors. BIOSENSORS 2024; 14:389. [PMID: 39194618 DOI: 10.3390/bios14080389] [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: 07/04/2024] [Revised: 08/08/2024] [Accepted: 08/10/2024] [Indexed: 08/29/2024]
Abstract
This study investigates the oxygen (O2) consumption of single cells during changes in their migration direction. This is the first integration of nanotopographies with an O2 biosensor in a platform, allowing the real-time monitoring of O2 consumption in cells and the ability to distinguish cells migrating in the same direction from those migrating in the opposite direction. Advanced nanofabrication technologies were used to pattern nanoholes or nanopillars on grating ridges, and their effects were evaluated using fluorescence microscopy, cell migration assays, and O2 consumption analysis. The results revealed that cells on the nanopillars over grating ridges exhibited an enhanced migration motility and more frequent directional changes. Additionally, these cells showed an increased number of protrusions and filopodia with denser F-actin areas and an increased number of dotted F-actin structures around the nanopillars. Dynamic metabolic responses were also evident, as indicated by the fluorescence intensity peaks of platinum octaethylporphyrin ketone dye, reflecting an increased O2 consumption and higher mitochondria activities, due to the higher energy required in response to directional changes. The study emphasizes the complex interplay between O2 consumption and cell migration directional changes, providing insights into biomaterial science and regenerative medicine. It suggests innovative designs for biomaterials that guide cell migration and metabolism, advocating nanoengineered platforms to harness the intricate relationships between cells and their microenvironments for therapeutic applications.
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Affiliation(s)
- Muting Wang
- Department of Electrical Engineering, Centre for Biosystems, Neuroscience, and Nanotechnology, City University of Hong Kong, Hong Kong, China
| | - Stella W Pang
- Department of Electrical Engineering, Centre for Biosystems, Neuroscience, and Nanotechnology, City University of Hong Kong, Hong Kong, China
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2
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Abaci A, Guvendiren M. 3D bioprinting of dense cellular structures within hydrogels with spatially controlled heterogeneity. Biofabrication 2024; 16:035027. [PMID: 38821144 DOI: 10.1088/1758-5090/ad52f1] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/17/2024] [Accepted: 05/31/2024] [Indexed: 06/02/2024]
Abstract
Embedded bioprinting is an emerging technology for precise deposition of cell-laden or cell-only bioinks to construct tissue like structures. Bioink is extruded or transferred into a yield stress hydrogel or a microgel support bath allowing print needle motion during printing and providing temporal support for the printed construct. Although this technology has enabled creation of complex tissue structures, it remains a challenge to develop a support bath with user-defined extracellular mimetic cues and their spatial and temporal control. This is crucial to mimic the dynamic nature of the native tissue to better regenerate tissues and organs. To address this, we present a bioprinting approach involving printing of a photocurable viscous support layer and bioprinting of a cell-only or cell-laden bioink within this viscous layer followed by brief exposure to light to partially crosslink the support layer. This approach does not require shear thinning behavior and is suitable for a wide range of photocurable hydrogels to be used as a support. It enables multi-material printing to spatially control support hydrogel heterogeneity including temporal delivery of bioactive cues (e.g. growth factors), and precise patterning of dense multi-cellular structures within these hydrogel supports. Here, dense stem cell aggregates are printed within methacrylated hyaluronic acid-based hydrogels with patterned heterogeneity to spatially modulate human mesenchymal stem cell osteogenesis. This study has significant impactions on creating tissue interfaces (e.g. osteochondral tissue) in which spatial control of extracellular matrix properties for patterned stem cell differentiation is crucial.
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Affiliation(s)
- Alperen Abaci
- Otto H. York Chemical and Materials Engineering Department, New Jersey Institute of Technology, Newark, NJ, United States of America
| | - Murat Guvendiren
- Otto H. York Chemical and Materials Engineering Department, New Jersey Institute of Technology, Newark, NJ, United States of America
- Bioengineering Department, New Jersey Institute of Technology, Newark, NJ, United States of America
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3
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Cheng Y, Pang SW. Biointerfaces with ultrathin patterns for directional control of cell migration. J Nanobiotechnology 2024; 22:158. [PMID: 38589901 PMCID: PMC11000378 DOI: 10.1186/s12951-024-02418-3] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/23/2023] [Accepted: 03/18/2024] [Indexed: 04/10/2024] Open
Abstract
In the context of wound healing and tissue regeneration, precise control of cell migration direction is deemed crucial. To address this challenge, polydimethylsiloxane (PDMS) platforms with patterned 10 nm thick TiOx in arrowhead shape were designed and fabricated. Remarkably, without tall sidewall constraints, MC3T3-E1 cells seeded on these platforms were constrained to migrate along the tips of the arrowheads, as the cells were guided by the asymmetrical arrowhead tips which provided large contact areas. To the best of our knowledge, this is the first study demonstrating the use of thin TiOx arrowhead pattern in combination with a cell-repellent PDMS surface to provide guided cell migration unidirectionally without tall sidewall constraints. Additionally, high-resolution fluorescence imaging revealed that the asymmetrical distribution of focal adhesions, triggered by the patterned TiOx arrowheads with arm lengths of 10, 20, and 35 μm, promoted cell adhesion and protrusion along the arrowhead tip direction, resulting in unidirectional cell migration. These findings have important implications for the design of biointerfaces with ultrathin patterns to precisely control cell migration. Furthermore, microelectrodes were integrated with the patterned TiOx arrowheads to enable dynamic monitoring of cell migration using impedance measurement. This microfluidic device integrated with thin layer of guiding pattern and microelectrodes allows simultaneous control of directional cell migration and characterization of the cell movement of individual MC3T3-E1 cells, offering great potential for the development of biosensors for single-cell monitoring.
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Grants
- CityU11207620, CityU11207821, CityU11205423 Research Grants Council of the Hong Kong Special Administrative Region, China
- CityU11207620, CityU11207821, CityU11205423 Research Grants Council of the Hong Kong Special Administrative Region, China
- 9360148, 9380062 Center for Biosystems, Neuroscience, and Nanotechnology (CBNN) of City University of Hong Kong
- 9360148, 9380062 Center for Biosystems, Neuroscience, and Nanotechnology (CBNN) of City University of Hong Kong
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Affiliation(s)
- Yijun Cheng
- Department of Electrical Engineering, City University of Hong Kong, Kowloon, Hong Kong, China
- Centre for Biosystems, Neuroscience, and Nanotechnology, City University of Hong Kong, Kowloon, Hong Kong, China
| | - Stella W Pang
- Department of Electrical Engineering, City University of Hong Kong, Kowloon, Hong Kong, China.
- Centre for Biosystems, Neuroscience, and Nanotechnology, City University of Hong Kong, Kowloon, Hong Kong, China.
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4
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Hong X, Xu Y, Pang SW. Enhanced motility and interaction of nasopharyngeal carcinoma with epithelial cells in confined microwells. LAB ON A CHIP 2023; 23:511-524. [PMID: 36632832 DOI: 10.1039/d2lc00616b] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/17/2023]
Abstract
The three-dimensional (3D) structure of the extracellular matrix and cell-cell contacts are two important cues to altering cell migration behavior and the tumor formation process. In this work, we designed and fabricated microwell arrays with a grating-patterned bottom in polydimethylsiloxane platforms to systematically study the effects of confinement, changes in topography, and cell-cell contacts on the migration behavior of nasopharyngeal carcinoma (NPC43) and immortalized nasopharyngeal epithelial (NP460) cells by time-lapse imaging. When two types of cells were co-cultured in microwells, the migration speed and spreading area of NPC43 cells were significantly increased, which might be attributed to the heterotypic cell-cell contacts with NP460 cells. On a flat surface, NPC43 cells could not form clusters due to the frequent interruptions by the active movements of NP460 cells. However, in 3D microwell arrays, clusters of NPC43 cells formed on the bottom surface while the majority of NP460 cells migrated onto the sidewalls. These cell clusters could be further processed to form spheroids for drug screening. These results also revealed that the 3D microenvironments and cell-cell contacts could have significant implications for NPC cell migration and initiation of tumor formation, which will provide insight for NPC progression and dissemination.
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Affiliation(s)
- Xiao Hong
- Department of Electrical Engineering and Centre for Biosystems, Neuroscience and Nanotechnology, City University of Hong Kong, Kowloon, Hong Kong, China.
| | - Yuanhao Xu
- Department of Electrical Engineering and Centre for Biosystems, Neuroscience and Nanotechnology, City University of Hong Kong, Kowloon, Hong Kong, China.
| | - Stella W Pang
- Department of Electrical Engineering and Centre for Biosystems, Neuroscience and Nanotechnology, City University of Hong Kong, Kowloon, Hong Kong, China.
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5
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Cheng Y, Pang SW. Effects of nanopillars and surface coating on dynamic traction force. MICROSYSTEMS & NANOENGINEERING 2023; 9:6. [PMID: 36620393 PMCID: PMC9814462 DOI: 10.1038/s41378-022-00473-0] [Citation(s) in RCA: 3] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Figures] [Subscribe] [Scholar Register] [Received: 07/17/2022] [Revised: 10/11/2022] [Accepted: 11/04/2022] [Indexed: 06/17/2023]
Abstract
The extracellular matrix serves as structural support for cells and provides biophysical and biochemical cues for cell migration. Topography, material, and surface energy can regulate cell migration behaviors. Here, the responses of MC3T3-E1 cells, including migration speed, morphology, and spreading on various platform surfaces, were investigated. Polydimethylsiloxane (PDMS) micropost sensing platforms with nanopillars, silicon oxide, and titanium oxide on top of the microposts were fabricated, and the dynamic cell traction force during migration was monitored. The relationships between various platform surfaces, migration behaviors, and cell traction forces were studied. Compared with the flat PDMS surface, cells on silicon oxide and titanium oxide surfaces showed reduced mobility and less elongation. On the other hand, cells on the nanopillar surface showed more elongation and a higher migration speed than cells on silicon oxide and titanium oxide surfaces. MC3T3-E1 cells on microposts with nanopillars exerted a larger traction force than those on flat PDMS microposts and had more filopodia and long protrusions. Understanding the relationships between platform surface condition, migration behavior, and cell traction force can potentially lead to better control of cell migration in biomaterials capable of promoting tissue repair and regeneration.
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Affiliation(s)
- Yijun Cheng
- Department of Electrical Engineering, City University of Hong Kong, Kowloon, Hong Kong, China
- Centre for Biosystems, Neuroscience, and Nanotechnology, City University of Hong Kong, Kowloon, Hong Kong, China
| | - Stella W. Pang
- Department of Electrical Engineering, City University of Hong Kong, Kowloon, Hong Kong, China
- Centre for Biosystems, Neuroscience, and Nanotechnology, City University of Hong Kong, Kowloon, Hong Kong, China
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6
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Fornaro M, Dipollina C, Giambalvo D, Garcia R, Sigerson C, Sharthiya H, Liu C, Nealey PF, Kristjansdottir K, Gasiorowski JZ. Submicron Topographically Patterned 3D Substrates Enhance Directional Axon Outgrowth of Dorsal Root Ganglia Cultured Ex Vivo. Biomolecules 2022; 12:biom12081059. [PMID: 36008953 PMCID: PMC9405616 DOI: 10.3390/biom12081059] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/31/2022] [Revised: 07/22/2022] [Accepted: 07/25/2022] [Indexed: 11/26/2022] Open
Abstract
A peripheral nerve injury results in disruption of the fiber that usually protects axons from the surrounding environment. Severed axons from the proximal nerve stump are capable of regenerating, but axons are exposed to a completely new environment. Regeneration recruits cells that produce and deposit key molecules, including growth factor proteins and fibrils in the extracellular matrix (ECM), thus changing the chemical and geometrical environment. The regenerating axons thus surf on a newly remodeled micro-landscape. Strategies to enhance and control axonal regeneration and growth after injury often involve mimicking the extrinsic cues that are found in the natural nerve environment. Indeed, nano- and micropatterned substrates have been generated as tools to guide axons along a defined path. The mechanical cues of the substrate are used as guides to orient growth or change the direction of growth in response to impediments or cell surface topography. However, exactly how axons respond to biophysical information and the dynamics of axonal movement are still poorly understood. Here we use anisotropic, groove-patterned substrate topography to direct and enhance sensory axonal growth of whole mouse dorsal root ganglia (DRG) transplanted ex vivo. Our results show significantly enhanced and directed growth of the DRG sensory fibers on the hemi-3D topographic substrates compared to a 0 nm pitch, flat control surface. By assessing the dynamics of axonal movement in time-lapse microscopy, we found that the enhancement was not due to increases in the speed of axonal growth, but to the efficiency of growth direction, ensuring axons minimize movement in undesired directions. Finally, the directionality of growth was reproduced on topographic patterns fabricated as fully 3D substrates, potentially opening new translational avenues of development incorporating these specific topographic feature sizes in implantable conduits in vivo.
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Affiliation(s)
- Michele Fornaro
- Department of Anatomy, College of Graduate Studies, Midwestern University, Downers Grove, IL 60515, USA;
- Chicago College of Osteopathic Medicine, Midwestern University, Downers Grove, IL 60515, USA; (C.D.); (D.G.); (C.S.)
- Correspondence: (M.F.); (J.Z.G.)
| | - Christopher Dipollina
- Chicago College of Osteopathic Medicine, Midwestern University, Downers Grove, IL 60515, USA; (C.D.); (D.G.); (C.S.)
- Department of Biomedical Sciences, College of Graduate Studies, Midwestern University, Downers Grove, IL 60515, USA; (R.G.); (K.K.)
| | - Darryl Giambalvo
- Chicago College of Osteopathic Medicine, Midwestern University, Downers Grove, IL 60515, USA; (C.D.); (D.G.); (C.S.)
- Department of Biomedical Sciences, College of Graduate Studies, Midwestern University, Downers Grove, IL 60515, USA; (R.G.); (K.K.)
| | - Robert Garcia
- Department of Biomedical Sciences, College of Graduate Studies, Midwestern University, Downers Grove, IL 60515, USA; (R.G.); (K.K.)
| | - Casey Sigerson
- Chicago College of Osteopathic Medicine, Midwestern University, Downers Grove, IL 60515, USA; (C.D.); (D.G.); (C.S.)
| | - Harsh Sharthiya
- Department of Anatomy, College of Graduate Studies, Midwestern University, Downers Grove, IL 60515, USA;
| | - Claire Liu
- Pritzker School of Molecular Engineering, University of Chicago, Chicago, IL 60637, USA; (C.L.); (P.F.N.)
| | - Paul F. Nealey
- Pritzker School of Molecular Engineering, University of Chicago, Chicago, IL 60637, USA; (C.L.); (P.F.N.)
| | - Kolbrun Kristjansdottir
- Department of Biomedical Sciences, College of Graduate Studies, Midwestern University, Downers Grove, IL 60515, USA; (R.G.); (K.K.)
| | - Joshua Z. Gasiorowski
- Department of Biomedical Sciences, College of Graduate Studies, Midwestern University, Downers Grove, IL 60515, USA; (R.G.); (K.K.)
- Correspondence: (M.F.); (J.Z.G.)
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7
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Engineered barriers regulate osteoblast cell migration in vertical direction. Sci Rep 2022; 12:4459. [PMID: 35292702 PMCID: PMC8924172 DOI: 10.1038/s41598-022-08262-5] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/22/2021] [Accepted: 03/01/2022] [Indexed: 11/29/2022] Open
Abstract
Considering cell migration is essential for understanding physiological processes and diseases. The vertical migration of cells in three dimensions is vital, but most previous studies on cell migration have only focused on two-dimensional horizontal migration. In this paper, cell migration in the vertical direction was studied. Barriers with a height of 1, 5, 10, and 25 µm with grating and arrows in channels as guiding patterns were fabricated. The effects of barrier height and guiding patterns on the vertical migration of MC3T3 cells were explored. The study revealed that taller barriers hinder vertical migration of MC3T3 cells, whereas grating and arrows in channels promote it. The time-lapse and micrograph images showed that as the barrier height increased, the cell climbing angle along the barrier sidewall decreased, and the time taken to climb over the barrier increased. These results indicate that taller barriers increase the difficulty of vertical migration by MC3T3 cells. To promote the vertical migration of MC3T3 cells, 10 µm tall barriers with 18° and 40° sloped sidewalls were fabricated. For barriers with 18° sloped sidewalls, the probability for MC3T3 cells to climb up and down the 10 µm tall barriers was 40.6% and 20.3%, respectively; this is much higher than the migration probability over vertical barriers. This study shows topographic guidance on the vertical migration of MC3T3 cells and broadens the understanding of cell migration in the vertical direction.
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8
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Satpathy A, Mohanty R, Rautray TR. Bio-mimicked guided tissue regeneration/guided bone regeneration membranes with hierarchical structured surfaces replicated from teak leaf exhibits enhanced bioactivity. J Biomed Mater Res B Appl Biomater 2021; 110:144-156. [PMID: 34227233 DOI: 10.1002/jbm.b.34898] [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: 11/24/2020] [Revised: 05/06/2021] [Accepted: 06/07/2021] [Indexed: 11/08/2022]
Abstract
Bio-mimicked GTR/GBR membranes with hierarchical structured surfaces were developed by direct and indirect replication of teak leaf surface. The membranes were fabricated using solvent casting method with customized templates. The surfaces obtained were those with micro-trichomes (MTS) and micro-depression (MDS) that resembled a whorling pattern. Structural details of the fabricated membrane surfaces were studied under stereomicroscope and scanning electron microscopy. Surface roughness, water wetting angle, water uptake, and degradation properties of the membranes were examined. The effects of the micro-patterned hierarchical structure on in vitro bioactivities of human osteoblast-like cells (MG63) and human gingival fibroblast cells HGF1-RT1 were studied. In vivo study carried out on rat skulls to assess the response of surrounding tissues for 4 weeks showed that the bio-mimicked MTS and MDS membrane surfaces enhanced the cell proliferation. The proliferation significantly increased with increasing surface roughness and decreasing contact angle. There was also an evidence of rapid new bone maturation with membranes with MTS. It is thus suggested that the teak leaf mimicked whorling patterned hierarchical structured surface is an important design for enhancing bioactivity.
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Affiliation(s)
- Anurag Satpathy
- Department of Periodontics and Oral Implantology, Institute of Dental Sciences, Siksha 'O'Anusandhan (Deemed to be University), Bhubaneswar, Odisha, India.,Biomaterials and Tissue Regeneration Lab, CETMS, Siksha 'O' Anusandhan (Deemed to be University), Bhubaneswar, Odisha, India
| | - Rinkee Mohanty
- Department of Periodontics and Oral Implantology, Institute of Dental Sciences, Siksha 'O'Anusandhan (Deemed to be University), Bhubaneswar, Odisha, India
| | - Tapash R Rautray
- Biomaterials and Tissue Regeneration Lab, CETMS, Siksha 'O' Anusandhan (Deemed to be University), Bhubaneswar, Odisha, India
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9
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Liu Y, Ren J, Zhang R, Hu S, Pang SW, Lam RHW. Spreading and Migration of Nasopharyngeal Normal and Cancer Cells on Microgratings. ACS APPLIED BIO MATERIALS 2021; 4:3224-3231. [DOI: 10.1021/acsabm.0c01610] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/12/2022]
Affiliation(s)
- Yi Liu
- Department of Biomedical Engineering, City University of Hong Kong, Kowloon, Hong Kong
- City University of Hong Kong Shenzhen Research Institute, Shenzhen, China
| | - Jifeng Ren
- Department of Biomedical Engineering, City University of Hong Kong, Kowloon, Hong Kong
- City University of Hong Kong Shenzhen Research Institute, Shenzhen, China
- School of Biomedical Engineering, Capital Medical University, Beijing 100069, China
| | - Ruolin Zhang
- Department of Electrical Engineering, City University of Hong Kong, Kowloon, Hong Kong
- Department of Biomedical Engineering, The Hong Kong Polytechnic University, Hung Hom, Hong Kong
| | - Shuhuan Hu
- BGI-Shenzhen, Shenzhen 518083, Guangdong China
| | - Stella W. Pang
- Department of Electrical Engineering, City University of Hong Kong, Kowloon, Hong Kong
- Centre for Biosystems, Neuroscience, and Nanotechnology, City University of Hong Kong, Kowloon, Hong Kong
| | - Raymond H. W. Lam
- Department of Biomedical Engineering, City University of Hong Kong, Kowloon, Hong Kong
- City University of Hong Kong Shenzhen Research Institute, Shenzhen, China
- Centre for Biosystems, Neuroscience, and Nanotechnology, City University of Hong Kong, Kowloon, Hong Kong
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10
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Migration of immortalized nasopharyngeal epithelia and carcinoma cells through porous membrane in 3D platforms. Biosci Rep 2021; 40:224916. [PMID: 32440676 PMCID: PMC7273909 DOI: 10.1042/bsr20194113] [Citation(s) in RCA: 6] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/27/2019] [Revised: 05/15/2020] [Accepted: 05/20/2020] [Indexed: 12/16/2022] Open
Abstract
In the present study, 3D biomimetic platforms were fabricated with guiding grating to mimic extracellular matrix topography, porous membrane to resemble the epithelial porous interface and trenches below to represent blood vessels as an in vitro tissue microenvironment. Fabrication technologies were developed to integrate the transparent biocompatible polydimethylsiloxane platforms with preciously controlled dimensions. Cell migration behaviors of an immortalized nasopharyngeal epithelial cell line (NP460) and a nasopharyngeal carcinoma cell line (NPC43) were studied on the 2D and 3D platforms. The NP460 and NPC43 cells traversing through the porous membrane and migrating in the trenches below were studied by time-lapse imaging. Before traversing through the pores, NP460 and NPC43 cells migrated around the pores but NPC43 cells had a lower migration speed with less lamellipodia spreading. After traversing to trenches below, NPC43 cells moved faster with an alternated elongated morphology (mesenchymal migration mode) and round morphology (amoeboid migration mode) compared with only mesenchymal migration mode for NP460 cells. The cell traversing probability through porous membrane on platforms with 30 μm wide trenches below was found to be the highest when the guiding grating was perpendicular to the trenches below and the lowest when the guiding grating was parallel to the trenches below. The present study shows important information on cell migration in complex 3D microenvironment with various dimensions and could provide insight for pathology and treatment of nasopharyngeal carcinoma.
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11
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Gaining Micropattern Fidelity in an NOA81 Microsieve Laser Ablation Process. MICROMACHINES 2020; 12:mi12010021. [PMID: 33375445 PMCID: PMC7823379 DOI: 10.3390/mi12010021] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 12/11/2020] [Revised: 12/22/2020] [Accepted: 12/23/2020] [Indexed: 12/25/2022]
Abstract
We studied the micropattern fidelity of a Norland Optical Adhesive 81 (NOA81) microsieve made by soft-lithography and laser micromachining. Ablation opens replicated cavities, resulting in three-dimensional (3D) micropores. We previously demonstrated that microsieves can capture cells by passive pumping. Flow, capture yield, and cell survival depend on the control of the micropore geometry and must yield high reproducibility within the device and from device to device. We investigated the NOA81 film thickness, the laser pulse repetition rate, the number of pulses, and the beam focusing distance. For NOA81 films spin-coated between 600 and 1200 rpm, the pulse number controls the breaching of films to form the pore’s aperture and dominates the process. Pulse repetition rates between 50 and 200 Hz had no observable influence. We also explored laser focal plane to substrate distance to find the most effective ablation conditions. Scanning electron micrographs (SEM) of focused ion beam (FIB)-cut cross sections of the NOA81 micropores and inverted micropore copies in polydimethylsiloxane (PDMS) show a smooth surface topology with minimal debris. Our studies reveal that the combined process allows for a 3D micropore quality from device to device with a large enough process window for biological studies.
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12
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Zhang WG, Liu ZY, Pang SW. Separation of nasopharyngeal epithelial cells from carcinoma cells on 3D scaffold platforms. Biotechnol Bioeng 2020; 118:1444-1455. [PMID: 33241857 DOI: 10.1002/bit.27640] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/14/2020] [Revised: 10/27/2020] [Accepted: 11/21/2020] [Indexed: 12/27/2022]
Abstract
Scaffold microstructures were developed to mimic a three-dimensional extracellular matrix in studying cell migration and invasion. The multiple-layer scaffold platforms were designed to investigate cell migration and separation from top to bottom layer. Two cell lines including immortalized nasopharyngeal epithelial (NP460) cells and nasopharyngeal carcinoma (NPC43) cells with Epstein-Barr virus were compared in this study. On one-layer platforms with trench depth of 15 µm, both NP460 and NPC43 cells were guided to migrate along the 18-µm-wide trenches, and exhibited random migration directions when the trench width was 10 or 50 µm. Nearly no cell was found to migrate in the 10-µm-wide trenches on one-layer platforms. However, the NP460 and NPC43 cells showed very different probability in the narrow trenches on two-layer platforms, making it possible to separate the nasopharyngeal epithelial cells from the carcinoma cells. Moreover, 1-µm deep grating topography on the top layer inhibited NP460 cells to migrate from top ridges to the 10-µm-wide trenches, but promoted such behavior for NPC43 cells. The results demonstrated in This study suggest that the engineered multiple-layer scaffold platforms could be used to separate carcinoma cells in NPC tumor as a potential treatment of NPC.
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Affiliation(s)
- W G Zhang
- Department of Electrical Engineering, City University of Hong Kong, Hong Kong.,Centre for Biosystems, Neuroscience, and Nanotechnology, City University of Hong Kong, Hong Kong
| | - Z Y Liu
- Department of Electrical Engineering, City University of Hong Kong, Hong Kong.,Centre for Biosystems, Neuroscience, and Nanotechnology, City University of Hong Kong, Hong Kong
| | - S W Pang
- Department of Electrical Engineering, City University of Hong Kong, Hong Kong.,Centre for Biosystems, Neuroscience, and Nanotechnology, City University of Hong Kong, Hong Kong
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13
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Refaaq FM, Chen X, Pang SW. Effects of topographical guidance cues on osteoblast cell migration. Sci Rep 2020; 10:20003. [PMID: 33203986 PMCID: PMC7672072 DOI: 10.1038/s41598-020-77103-0] [Citation(s) in RCA: 16] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/21/2020] [Accepted: 11/05/2020] [Indexed: 12/13/2022] Open
Abstract
Cell migration is a fundamental process that is crucial for many biological functions in the body such as immune responses and tissue regeneration. Dysregulation of this process is associated with cancer metastasis. In this study, polydimethylsiloxane platforms with various topographical features were engineered to explore the influence of guiding patterns on MC3T3-E1 osteoblast cell migration. Focusing on the guiding effects of grating patterns, variations such as etch depth, pattern discontinuity, and bending angles were investigated. In all experiments, MC3T3-E1 cells on patterned surfaces demonstrated a higher migration speed and alignment when compared to flat surfaces. The study revealed that an increase in etch depth from 150 nm to 4.5 μm enhanced cell alignment and elongation along the grating patterns. In the presence of discontinuous elements, cell migration speed was accelerated when compared to gratings of the same etch depth. These results indicated that cell directionality preference was influenced by a high level of pattern discontinuity. On patterns with bends, cells were more inclined to reverse on 45° bends, with 69% of cells reversing at least once, compared to 54% on 135° bends. These results are attributed to cell morphology and motility mechanisms that are associated with surface topography, where actin filament structures such as filopodia and lamellipodia are essential in sensing the surrounding environment and controlling cell displacement. Knowledge of geometric guidance cues could provide a better understanding on how cell migration is influenced by extracellular matrix topography in vivo.
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Affiliation(s)
- F M Refaaq
- Department of Electrical Engineering, Centre for Biosystems, Neuroscience, and Nanotechnology, City University of Hong Kong, Kowloon, Hong Kong, China
| | - X Chen
- Department of Electrical Engineering, Centre for Biosystems, Neuroscience, and Nanotechnology, City University of Hong Kong, Kowloon, Hong Kong, China
| | - S W Pang
- Department of Electrical Engineering, Centre for Biosystems, Neuroscience, and Nanotechnology, City University of Hong Kong, Kowloon, Hong Kong, China.
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14
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Lam BP, Cheung SKC, Lam YW, Pang SW. Microenvironmental topographic cues influence migration dynamics of nasopharyngeal carcinoma cells from tumour spheroids. RSC Adv 2020; 10:28975-28983. [PMID: 35520045 PMCID: PMC9055862 DOI: 10.1039/d0ra03740k] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/26/2020] [Accepted: 07/22/2020] [Indexed: 12/13/2022] Open
Abstract
Tumour metastasis is a complex process that strongly influences the prognosis and treatment of cancer. Apart from intracellular factors, recent studies have indicated that metastasis also depends on microenvironmental factors such as the biochemical, mechanical and topographical properties of the surrounding extracellular matrix (ECM) of tumours. In this study, as a proof of concept, we conducted tumour spheroid dissemination assay on engineered surfaces with micrograting patterns. Nasopharyngeal spheroids were generated by the 3D culture of nasopharyngeal carcinoma (NPC43) cells, a newly established cell line that maintains a high level of Epstein–Barr virus, a hallmark of NPC. Three types of collagen I-coated polydimethylsiloxane (PDMS) substrates were used, with 15 μm deep “trenches” that grated the surfaces: (a) 40/10 μm ridges (R)/trenches (T), (b) 18/18 μm (R/T) and (c) 50/50 μm (R/T). The dimensions of these patterns were designed to test how various topographical cues, different with respect to the size of tumour spheroids and individual NPC43 cells, might affect dissemination behaviours. Spreading efficiencies on all three patterned surfaces, especially 18/18 μm (R/T), were lower than that on flat PDMS surface. The outspreading cell sheets on flat and 40/10 μm (R/T) surfaces were relatively symmetrical but appeared ellipsoid and aligned with the main axes of the 18/18 μm (R/T) and 50/50 μm (R/T) grating platforms. Focal adhesions (FAs) were found to preferentially formed on the ridges of all patterns. The number of FAs per spheroid was strongly influenced by the grating pattern, with the least FAs on the 40/10 μm (R/T) and the most on the 50/50 μm (R/T) substrate. Taken together, these data indicate a previously unknown effect of surface topography on the efficiency and directionality of cancer cell spreading from tumour spheroids, suggesting that topography, like ECM biochemistry and stiffness, can influence the migration dynamics in 3D cell culture models. Investigation of collective migration of nasopharyngeal carcinoma cells from tumour spheroids on micro-engineered platforms that induced asymmetrical tumour shape.![]()
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Affiliation(s)
- Bowie P. Lam
- Department of Electrical Engineering
- City University of Hong Kong
- Hong Kong
- Centre for Biosystems, Neuroscience, and Nanotechnology
- City University of Hong Kong
| | - Sarah K. C. Cheung
- Centre for Biosystems, Neuroscience, and Nanotechnology
- City University of Hong Kong
- Hong Kong
- Department of Chemistry
- City University of Hong Kong
| | - Yun W. Lam
- Centre for Biosystems, Neuroscience, and Nanotechnology
- City University of Hong Kong
- Hong Kong
- Department of Chemistry
- City University of Hong Kong
| | - Stella W. Pang
- Department of Electrical Engineering
- City University of Hong Kong
- Hong Kong
- Centre for Biosystems, Neuroscience, and Nanotechnology
- City University of Hong Kong
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15
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Tsang C, Liu Z, Zhang W, You C, Jones G, Tsao S, Pang S. Integration of biochemical and topographic cues for the formation and spatial distribution of invadosomes in nasopharyngeal epithelial cells. Acta Biomater 2020; 101:168-182. [PMID: 31683015 DOI: 10.1016/j.actbio.2019.10.043] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/26/2019] [Revised: 10/16/2019] [Accepted: 10/30/2019] [Indexed: 01/03/2023]
Abstract
Invadosomes are invasive protrusions generated by cells which can secrete matrix metalloproteinases for focal digestion of extracellular matrix. They also aid invasive cancer cells in their transmigration through vascular endothelium. However, how the physical and chemical cues in a three-dimensional (3D) system signal the spatial localization of invadosomes remains largely unknown. Here we study the topographic guidance of invadosome formation in invasive nasopharyngeal cells under the stimulation of an inflammatory cytokine, TGF-β1, using engineered gratings with different width and depth. We first report that TGF-β1 can act as an external signal to upregulate the formation of invadosomes with a random distribution on a plane 2D surface. When the cells were seeded on parallel 3D gratings of 5 µm width and 1 µm depth, most of the invadosomes aligned to the edges of the gratings, indicating a topographic cue to the control of invadosome localization. While the number of invadosomes per cell were not upregulated when the cells were seeded on 3D topography, guidance of invadosomes localization to edges is correlated with cell migration directionality on 1 µm deep gratings. Invadosomes preferentially form at edges when the cells move at a lower speed and are guided along narrow gratings. The invadosomes forming at 3D edges also have a longer half-life than those forming on a plane surface. These data suggest that there are integrated biochemical and 3D geometric cues underlying the spatial regulation of invasive structures so as to elicit efficient invasion or metastasis of cells. STATEMENT OF SIGNIFICANCE: Nasopharyngeal cells were integrated with the biological cues and matrix topography to govern the activity and spatial distribution of invadosomes. The biochemical induction of invadosome formation by TGF-β1 in nasopharyngeal cells was observed. When the cells were seeded on parallel 3D gratings, most of the invadosomes aligned to the edges of the gratings due to topographical induced invadosome localization. While the number of invadosomes per cell were not upregulated, guidance of invadosomes localization to edges is correlated with cell migration directionality on 1 µm deep gratings. Invadosomes preferentially form at edges with a higher stability when the cells are guided along narrow gratings. The integrated biochemical and 3D geometric cues could elicit efficient invasion or metastasis of cells.
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16
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Xu Y, Pang SW. Natural killer cell migration control in microchannels by perturbations and topography. LAB ON A CHIP 2019; 19:2466-2475. [PMID: 31225540 DOI: 10.1039/c9lc00356h] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/09/2023]
Abstract
Natural killer (NK) cells are lymphocytes which play an important role in the immune system by recognizing and killing potentially malignant cells without antigen sensitization, and could be utilized in cancer therapy. NK cell migration is an essential process to find and kill target cells, which is well known to be driven by the chemotaxis effect. NK cells also experience a topographical effect induced by the extracellular matrix (ECM) during their migration. However, topographical effects on NK cell locomotion in three dimensional (3D) environments are not well studied yet. In this work, polydimethylsiloxane based platforms containing microchannels with different types of perturbations and decorated with various surface patterns were fabricated to systematically study the topographical effect on NK cell migration with and without the chemotaxis effect. The results showed that perturbation sites in channels induced pauses and reversals in chemotaxis driven NK cell migration. Surface topography such as gratings in confined environments could introduce directional preference to NK cell movement even without chemoattractants. These findings showed that NK cell migration could be controlled by contact guidance, which provides future possibility to manipulate NK cell migration in controlled in vitro bioengineering systems. Results in this study showed that the complex topography of 3D microenvironments in the ECM could have significant effects on NK cell migration in different tissues and organs, and provided insight for explaining the dynamics of NK cell activities in clinical experiments.
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Affiliation(s)
- Yuanhao Xu
- Department of Electronic Engineering, Center for Biosystems, Neuroscience, and Nanotechnology, City University of Hong Kong, Hong Kong.
| | - Stella W Pang
- Department of Electronic Engineering, Center for Biosystems, Neuroscience, and Nanotechnology, City University of Hong Kong, Hong Kong.
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17
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Hui J, Pang S. Cell traction force in a confined microenvironment with double-sided micropost arrays. RSC Adv 2019; 9:8575-8584. [PMID: 35518671 PMCID: PMC9061871 DOI: 10.1039/c8ra10170a] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/11/2018] [Accepted: 03/07/2019] [Indexed: 11/21/2022] Open
Abstract
Three-dimensional (3D) cell migrations are regulated by force interactions between cells and a 3D extracellular matrix (ECM). Mapping the 3D traction force generated by cells on the surrounding ECM with controlled confinement and contact area will be useful in understanding cell migration. In this study, double-sided micropost arrays were fabricated. The cell traction force was mapped by microposts on the top and bottom of opposing surfaces with a controlled separating distance to create different confinements. The density of micropost arrays was modified to investigate the effect of cell contact area on 3D traction force development. Using MC3T3-E1 osteoblastic cells, the leading traction force was found to increase with additional contact surface on the top. Summing force vectors on both surfaces, a large force imbalance was found from the leading to trailing regions for fast migrating cells. With 10 μm separation and densely arranged microposts, the traction force on the top surface was the largest at 28.6 ± 2.5 nN with the highest migration speed of 0.61 ± 0.07 μm min−1. Decreasing the density of the top micropost arrays resulted in a reduced traction force on the top and lower migration speed. With 15 μm separation, the cell traction force on the top and migration speed further decreased simultaneously. These results revealed traction force development on 3D ECM with varied degrees of confinement and contact area, which is important in regulating 3D cell migration. Double-sided micropost arrays to monitor three-dimensional cell traction force development over time on top and bottom surfaces with controlled confinement and contact area.![]()
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Affiliation(s)
- Jianan Hui
- Department of Electronic Engineering
- City University of Hong Kong
- China
- Center for Biosystems, Neuroscience, and Nanotechnology
- City University of Hong Kong
| | - Stella W. Pang
- Department of Electronic Engineering
- City University of Hong Kong
- China
- Center for Biosystems, Neuroscience, and Nanotechnology
- City University of Hong Kong
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18
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Moussa HI, Logan M, Wong K, Rao Z, Aucoin MG, Tsui TY. Nanoscale-Textured Tantalum Surfaces for Mammalian Cell Alignment. MICROMACHINES 2018; 9:E464. [PMID: 30424397 PMCID: PMC6187670 DOI: 10.3390/mi9090464] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 07/12/2018] [Revised: 09/07/2018] [Accepted: 09/10/2018] [Indexed: 02/06/2023]
Abstract
Tantalum is one of the most important biomaterials used for surgical implant devices. However, little knowledge exists about how nanoscale-textured tantalum surfaces affect cell morphology. Mammalian (Vero) cell morphology on tantalum-coated comb structures was studied using high-resolution scanning electron microscopy and fluorescence microscopy. These structures contained parallel lines and trenches with equal widths in the range of 0.18 to 100 μm. Results showed that as much as 77% of adherent cell nuclei oriented within 10° of the line axes when deposited on comb structures with widths smaller than 10 μm. However, less than 20% of cells exhibited the same alignment performance on blanket tantalum films or structures with line widths larger than 50 μm. Two types of line-width-dependent cell morphology were observed. When line widths were smaller than 0.5 μm, nanometer-scale pseudopodia bridged across trench gaps without contacting the bottom surfaces. In contrast, pseudopodia structures covered the entire trench sidewalls and the trench bottom surfaces of comb structures with line-widths larger than 0.5 μm. Furthermore, results showed that when a single cell simultaneously adhered to multiple surface structures, the portion of the cell contacting each surface reflected the type of morphology observed for cells individually contacting the surfaces.
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Affiliation(s)
- Hassan I Moussa
- Department of Chemical Engineering, University of Waterloo, Waterloo, ON N2L 3G1, Canada.
- Waterloo Institute of Nanotechnology, University of Waterloo, Waterloo, ON N2L 3G1, Canada.
| | - Megan Logan
- Department of Chemical Engineering, University of Waterloo, Waterloo, ON N2L 3G1, Canada.
- Waterloo Institute of Nanotechnology, University of Waterloo, Waterloo, ON N2L 3G1, Canada.
| | - Kingsley Wong
- Department of Chemical Engineering, University of Waterloo, Waterloo, ON N2L 3G1, Canada.
- Waterloo Institute of Nanotechnology, University of Waterloo, Waterloo, ON N2L 3G1, Canada.
| | - Zheng Rao
- Department of Chemical Engineering, University of Waterloo, Waterloo, ON N2L 3G1, Canada.
- Waterloo Institute of Nanotechnology, University of Waterloo, Waterloo, ON N2L 3G1, Canada.
| | - Marc G Aucoin
- Department of Chemical Engineering, University of Waterloo, Waterloo, ON N2L 3G1, Canada.
- Waterloo Institute of Nanotechnology, University of Waterloo, Waterloo, ON N2L 3G1, Canada.
| | - Ting Y Tsui
- Department of Chemical Engineering, University of Waterloo, Waterloo, ON N2L 3G1, Canada.
- Waterloo Institute of Nanotechnology, University of Waterloo, Waterloo, ON N2L 3G1, Canada.
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19
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Integrated Circuit-Based Biofabrication with Common Biomaterials for Probing Cellular Biomechanics. Trends Biotechnol 2016; 34:171-186. [DOI: 10.1016/j.tibtech.2015.11.005] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/11/2015] [Revised: 11/03/2015] [Accepted: 11/18/2015] [Indexed: 01/10/2023]
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20
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Zhou SF, Gopalakrishnan S, Xu YH, Yang J, Lam YW, Pang SW. A Unidirectional Cell Switching Gate by Engineering Grating Length and Bending Angle. PLoS One 2016; 11:e0147801. [PMID: 26821058 PMCID: PMC4731054 DOI: 10.1371/journal.pone.0147801] [Citation(s) in RCA: 14] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/09/2015] [Accepted: 01/09/2016] [Indexed: 11/18/2022] Open
Abstract
On a microgrooved substrate, cells migrate along the pattern, and at random positions, reverse their directions. Here, we demonstrate that these reversals can be controlled by introducing discontinuities to the pattern. On "V-shaped grating patterns", mouse osteogenic progenitor MC3T3-E1 cells reversed predominately at the bends and the ends. The patterns were engineered in a way that the combined effects of angle- and length-dependence could be examined in addition to their individual effects. Results show that when the bend was placed closer to one end, migration behaviour of cells depends on their direction of approach. At an obtuse bend (135°), more cells reversed when approaching from the long segment than from the short segment. But at an acute bend (45°), this relationship was reversed. Based on this anisotropic behaviour, the designed patterns effectively allowed cells to move in one direction but blocked migrations in the opposing direction. This study demonstrates that by the strategic placement of bends and ends on grating patterns, we can engineer effective unidirectional switching gates that can control the movement of adherent cells. The knowledge developed in this study could be utilised in future cell sorting or filtering platforms without the need for chemotaxis or microfluidic control.
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Affiliation(s)
- Shu Fan Zhou
- Department of Electronic Engineering, City University of Hong Kong, Kowloon, Hong Kong
- Centre for Biosystems, Neuroscience, and Nanotechnology, City University of Hong Kong, Kowloon, Hong Kong
| | - Singaram Gopalakrishnan
- Centre for Biosystems, Neuroscience, and Nanotechnology, City University of Hong Kong, Kowloon, Hong Kong
- Department of Biology and Chemistry, City University of Hong Kong, Kowloon, Hong Kong
| | - Yuan Hao Xu
- Department of Electronic Engineering, City University of Hong Kong, Kowloon, Hong Kong
- Centre for Biosystems, Neuroscience, and Nanotechnology, City University of Hong Kong, Kowloon, Hong Kong
| | - Jie Yang
- Centre for Biosystems, Neuroscience, and Nanotechnology, City University of Hong Kong, Kowloon, Hong Kong
- Department of Biology and Chemistry, City University of Hong Kong, Kowloon, Hong Kong
| | - Yun Wah Lam
- Centre for Biosystems, Neuroscience, and Nanotechnology, City University of Hong Kong, Kowloon, Hong Kong
- Department of Biology and Chemistry, City University of Hong Kong, Kowloon, Hong Kong
| | - Stella W Pang
- Department of Electronic Engineering, City University of Hong Kong, Kowloon, Hong Kong
- Centre for Biosystems, Neuroscience, and Nanotechnology, City University of Hong Kong, Kowloon, Hong Kong
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21
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Premnath P, Venkatakrishnan K, Tan B. Programming cancer through phase-functionalized silicon based biomaterials. Sci Rep 2015; 5:10826. [PMID: 26043430 PMCID: PMC4455305 DOI: 10.1038/srep10826] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/16/2014] [Accepted: 04/17/2015] [Indexed: 11/09/2022] Open
Abstract
Applications of biomaterials in cancer therapy has been limited to drug delivery systems and markers in radiation therapy. In this article, we introduce the concept of phase-functionalization of silicon to preferentially select cancer cell populations for survival in a catalyst and additive free approach. Silicon is phase-functionalized by the interaction of ultrafast laser pulses, resulting in the formation of rare phases of SiO2 in conjunction with differing silicon crystal lattices. The degree of phase-functionalization is programmed to dictate the degree of repulsion of cancer cells. Unstable phases of silicon oxides are synthesized during phase-functionalization and remain stable at ambient conditions. This change in phase of silicon as well as formation of oxides contributes to changes in surface chemistry as well as surface energy. These material properties elicit in precise control of migration, cytoskeleton shape, direction and population. To the best of our knowledge, phase-functionalized silicon without any changes in topology or additive layers and its applications in cancer therapy has not been reported before. This unique programmable phase-functionalized silicon has the potential to change current trends in cancer research and generate focus on biomaterials as cancer repelling or potentially cancer killing surfaces.
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Affiliation(s)
- Priyatha Premnath
- Department of Mechanical and Industrial Engineering, Ryerson University, 350 Victoria Street, Toronto M5B2K3
| | - Krishnan Venkatakrishnan
- Department of Mechanical and Industrial Engineering, Ryerson University, 350 Victoria Street, Toronto M5B2K3
| | - Bo Tan
- Department of Aerospace Engineering, Ryerson University, 350 Victoria Street, Toronto M5B2K3
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22
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Li W, Tang QY, Jadhav AD, Narang A, Qian WX, Shi P, Pang SW. Large-scale topographical screen for investigation of physical neural-guidance cues. Sci Rep 2015; 5:8644. [PMID: 25728549 DOI: 10.1038/srep08644] [Citation(s) in RCA: 58] [Impact Index Per Article: 6.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/22/2014] [Accepted: 01/29/2015] [Indexed: 12/23/2022] Open
Abstract
A combinatorial approach was used to present primary neurons with a large library of topographical features in the form of micropatterned substrate for high-throughput screening of physical neural-guidance cues that can effectively promote different aspects of neuronal development, including axon and dendritic outgrowth. Notably, the neuronal-guidance capability of specific features was automatically identified using a customized image processing software, thus significantly increasing the screening throughput with minimal subjective bias. Our results indicate that the anisotropic topographies promote axonal and in some cases dendritic extension relative to the isotropic topographies, while dendritic branching showed preference to plain substrates over the microscale features. The results from this work can be readily applied towards engineering novel biomaterials with precise surface topography that can serve as guidance conduits for neuro-regenerative applications. This novel topographical screening strategy combined with the automated processing capability can also be used for high-throughput screening of chemical or genetic regulatory factors in primary neurons.
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Affiliation(s)
- Wei Li
- 1] Department of Mechanical and Biomedical Engineering, City University of Hong Kong, Kowloon, Hong Kong SAR, China [2] Center for Biosystems, Neuroscience, and Nanotechnology, City University of Hong Kong, Kowloon, Hong Kong SAR, China
| | - Qing Yuan Tang
- 1] Department of Electronic Engineering, City University of Hong Kong, Kowloon, Hong Kong SAR, China [2] Center for Biosystems, Neuroscience, and Nanotechnology, City University of Hong Kong, Kowloon, Hong Kong SAR, China
| | - Amol D Jadhav
- 1] Department of Mechanical and Biomedical Engineering, City University of Hong Kong, Kowloon, Hong Kong SAR, China [2] Center for Biosystems, Neuroscience, and Nanotechnology, City University of Hong Kong, Kowloon, Hong Kong SAR, China
| | - Ankit Narang
- 1] Department of Mechanical and Biomedical Engineering, City University of Hong Kong, Kowloon, Hong Kong SAR, China [2] Center for Biosystems, Neuroscience, and Nanotechnology, City University of Hong Kong, Kowloon, Hong Kong SAR, China
| | - Wei Xian Qian
- 1] Department of Electronic Engineering, City University of Hong Kong, Kowloon, Hong Kong SAR, China [2] Center for Biosystems, Neuroscience, and Nanotechnology, City University of Hong Kong, Kowloon, Hong Kong SAR, China [3] School of Electronic and Optical Engineering, Nanjing University of Science and Technology, Nanjing, Jiangsu, China
| | - Peng Shi
- 1] Department of Mechanical and Biomedical Engineering, City University of Hong Kong, Kowloon, Hong Kong SAR, China [2] Center for Biosystems, Neuroscience, and Nanotechnology, City University of Hong Kong, Kowloon, Hong Kong SAR, China [3] Shenzhen Research Institute, City University of Hong Kong Shenzhen, Guangdong, China
| | - Stella W Pang
- 1] Department of Electronic Engineering, City University of Hong Kong, Kowloon, Hong Kong SAR, China [2] Center for Biosystems, Neuroscience, and Nanotechnology, City University of Hong Kong, Kowloon, Hong Kong SAR, China
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23
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Tang QY, Qian WX, Xu YH, Gopalakrishnan S, Wang JQ, Lam YW, Pang SW. Control of cell migration direction by inducing cell shape asymmetry with patterned topography. J Biomed Mater Res A 2014; 103:2383-93. [PMID: 25430523 DOI: 10.1002/jbm.a.35378] [Citation(s) in RCA: 25] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/16/2014] [Revised: 11/11/2014] [Accepted: 11/20/2014] [Indexed: 01/23/2023]
Abstract
In this study, we explored the concept of introducing asymmetry to cell shapes by patterned cell culture substrates, and investigated the consequence of this induced asymmetry to cell migration behaviors. Three patterns, named "Squares", "Grating", and "Arcs" were fabricated, representing different levels of rotational asymmetry. Using time-lapse imaging, we systematically compared the motility and directionality of mouse osteoblastic cells MC3T3-E1 cultured on these patterns. Cells were found to move progressively faster on "Arcs" than on "Grating", and cells on "Squares" were the slowest, suggesting that cell motility correlates with the level of rotational asymmetry of the repeating units of the pattern. Among these three patterns, on the "Arcs" pattern, the least symmetrical one, cells not only moved with the highest velocity but also the strongest directional persistence. Although this enhanced motility was not associated with the detected number of focal adhesion sites in the cells, the pattern asymmetry was reflected in the asymmetrical cell spreading. Cells on the "Arcs" pattern consistently displayed larger cytoplasmic protrusion on one side of the cell. This asymmetry in cell shape determined the direction and speed of cell migration. These observations suggest that topographical patterns that enhance the imbalance between the leading and trailing fronts of adherent cells will increase cell speed and control movement directions. Our discovery shows that complex cell behaviors such as the direction of cell movement are influenced by simple geometrical principles, which can be utilized as the design foundation for platforms that guide and sort cultured cells.
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Affiliation(s)
- Q Y Tang
- Department of Electronic Engineering, City University of Hong Kong, Hong Kong.,Center for Biosystems, Neuroscience, and Nanotechnology, City University of Hong Kong, Hong Kong
| | - W X Qian
- Department of Electronic Engineering, City University of Hong Kong, Hong Kong.,Center for Biosystems, Neuroscience, and Nanotechnology, City University of Hong Kong, Hong Kong.,School of Electronic and Optical Engineering, Nanjing University of Science and Technology, China
| | - Y H Xu
- Department of Electronic Engineering, City University of Hong Kong, Hong Kong.,Center for Biosystems, Neuroscience, and Nanotechnology, City University of Hong Kong, Hong Kong
| | - S Gopalakrishnan
- Center for Biosystems, Neuroscience, and Nanotechnology, City University of Hong Kong, Hong Kong.,Department of Biology and Chemistry, City University of Hong Kong, Hong Kong
| | - J Q Wang
- Department of Electronic Engineering, City University of Hong Kong, Hong Kong.,Center for Biosystems, Neuroscience, and Nanotechnology, City University of Hong Kong, Hong Kong.,College of Electronic Science and Technology, Dalian University of Technology, China
| | - Y W Lam
- Center for Biosystems, Neuroscience, and Nanotechnology, City University of Hong Kong, Hong Kong.,Department of Biology and Chemistry, City University of Hong Kong, Hong Kong
| | - S W Pang
- Department of Electronic Engineering, City University of Hong Kong, Hong Kong.,Center for Biosystems, Neuroscience, and Nanotechnology, City University of Hong Kong, Hong Kong
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