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Ušaj M, Pavlin M, Kandušer M. Feasibility Study for the Use of Gene Electrotransfer and Cell Electrofusion as a Single-Step Technique for the Generation of Activated Cancer Cell Vaccines. J Membr Biol 2024:10.1007/s00232-024-00320-5. [PMID: 39133276 DOI: 10.1007/s00232-024-00320-5] [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: 04/17/2024] [Accepted: 07/20/2024] [Indexed: 08/13/2024]
Abstract
Cell-based therapies hold great potential for cancer immunotherapy. This approach is based on manipulation of dendritic cells to activate immune system against specific cancer antigens. For the development of an effective cell vaccine platform, gene transfer, and cell fusion have been used for modification of dendritic or tumor cells to express immune (co)stimulatory signals and to load dendritic cells with tumor antigens. Both, gene transfer and cell fusion can be achieved by single technique, a cell membrane electroporation. The cell membrane exposed to external electric field becomes temporarily permeable, enabling introduction of genetic material, and also fusogenic, enabling the fusion of cells in the close contact. We tested the feasability of combining gene electrotransfer and electrofusion into a single-step technique and evaluated the effects of electroporation buffer, pulse parameters, and cell membrane fluidity for single or combined method of gene delivery or cell fusdion. We determined the percentage of fused cells expressing green fluorescence protein (GFP) in a murine cell model of melanoma B16F1, cell line used in our previous studies. Our results suggest that gene electrotransfer and cell electrofusion can be applied in a single step. The percentage of viable hybrid cells expressing GFP depends on electric pulse parameters and the composition of the electroporation buffer. Furthermore, our results suggest that cell membrane fluidity is not related to the efficiency of the gene electrotransfer and electrofusion. The protocol is compatible with microfluidic devices, however further optimization of electric pulse parameters and buffers is still needed.
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Affiliation(s)
- Marko Ušaj
- Faculty of Health and Life Sciences, Department of Chemistry and Biomedical Sciences, Linnaeus University, 391 82, Kalmar, Sweden
| | - Mojca Pavlin
- Faculty of Medicine, Institute of Biophysics, University of Ljubljana, Vrazov Trg 2, 1000, Ljubljana, Slovenia
- Faculty of Electrical Engineering, Group for Nano and Biotechnological Applications, University of Ljubljana, Tržaška 25, 1000, Ljubljana, Slovenia
| | - Maša Kandušer
- Institute for Pharmacy, Faculty of Pharmacy, University of Ljubljana, Aškerčeva 7, 1000, Ljubljana, Slovenia.
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Sun H, Hu N, Wang J. Application of Microfluidic Technology in Antibody Screening. Biotechnol J 2022; 17:e2100623. [PMID: 35481726 DOI: 10.1002/biot.202100623] [Citation(s) in RCA: 5] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/16/2021] [Revised: 04/13/2022] [Accepted: 04/23/2022] [Indexed: 11/07/2022]
Abstract
Specific antibodies are widely used in the biomedical field. Current screening methods for specific antibodies mainly involve hybridoma technology and antibody engineering techniques. However, these technologies suffer from tedious screening processes, long preparation periods, high costs, low efficiency, and a degree of automation, which have become a bottleneck for the screening of specific antibodies. To overcome these difficulties, microfluidics has been developed as a promising technology for high-throughput screening and high purity of antibody. In this review, we provide an overview of the recent advances in microfluidic applications for specific antibody screening. In particular, hybridoma technology and four antibody engineering techniques (including phage display, single B cell antibody screening, antibody expression, and cell-free protein synthesis) based on microfluidics have been introduced, challenges, and the future outlook of these technologies are also discussed. This article is protected by copyright. All rights reserved.
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Affiliation(s)
- Heng Sun
- Key Laboratory of Biorheological Science and Technology, Ministry of Education, College of Bioengineering, Chongqing University, Chongqing, 400044, China
| | - Ning Hu
- Key Laboratory of Biorheological Science and Technology, Ministry of Education, College of Bioengineering, Chongqing University, Chongqing, 400044, China
| | - Jianhua Wang
- Key Laboratory of Biorheological Science and Technology, Ministry of Education, College of Bioengineering, Chongqing University, Chongqing, 400044, China
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Wang L, Zhao C, Wijnperlé D, Duits MHG, Mugele F. Design of a hybrid advective-diffusive microfluidic system with ellipsometric detection for studying adsorption. BIOMICROFLUIDICS 2016; 10:034113. [PMID: 27375818 PMCID: PMC4902818 DOI: 10.1063/1.4953105] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 04/10/2016] [Accepted: 05/19/2016] [Indexed: 06/06/2023]
Abstract
Establishing and maintaining concentration gradients that are stable in space and time is critical for applications that require screening the adsorption behavior of organic or inorganic species onto solid surfaces for wide ranges of fluid compositions. In this work, we present a design of a simple and compact microfluidic device based on steady-state diffusion of the analyte, between two control channels where liquid is pumped through. The device generates a near-linear distribution of concentrations. We demonstrate this via experiments with dye solutions and comparison to finite-element numerical simulations. In a subsequent step, the device is combined with total internal reflection ellipsometry to study the adsorption of (cat)ions on silica surfaces from CsCl solutions at variable pH. Such a combined setup permits a fast determination of an adsorption isotherm. The measured optical thickness is compared to calculations from a triple layer model for the ion distribution, where surface complexation reactions of the silica are taken into account. Our results show a clear enhancement of the ion adsorption with increasing pH, which can be well described with reasonable values for the equilibrium constants of the surface reactions.
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Affiliation(s)
- Lei Wang
- Physics of Complex Fluids Group, MESA+ Institute, University of Twente , P.O. Box 217, 7500 AE Enschede, The Netherlands
| | - Cunlu Zhao
- Physics of Complex Fluids Group, MESA+ Institute, University of Twente , P.O. Box 217, 7500 AE Enschede, The Netherlands
| | - Daniel Wijnperlé
- Physics of Complex Fluids Group, MESA+ Institute, University of Twente , P.O. Box 217, 7500 AE Enschede, The Netherlands
| | - Michel H G Duits
- Physics of Complex Fluids Group, MESA+ Institute, University of Twente , P.O. Box 217, 7500 AE Enschede, The Netherlands
| | - Frieder Mugele
- Physics of Complex Fluids Group, MESA+ Institute, University of Twente , P.O. Box 217, 7500 AE Enschede, The Netherlands
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Robinson T, Verboket PE, Eyer K, Dittrich PS. Controllable electrofusion of lipid vesicles: initiation and analysis of reactions within biomimetic containers. LAB ON A CHIP 2014; 14:2852-9. [PMID: 24911345 DOI: 10.1039/c4lc00460d] [Citation(s) in RCA: 23] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/18/2023]
Abstract
We present a microfluidic device that is able to trap multiple giant unilamellar vesicles (GUVs) and initiate electrofusion via integrated microelectrodes. PDMS posts were designed to trap and isolate two or more vesicles. Electrodes patterned onto the glass surface of the microchannels are able to apply a short, high voltage pulse across the traps for controllable electrofusion of the GUVs. The entire array of traps and electrodes are designed such that an average of 60 individual fusion experiments can be performed on-chip. An assay based on Förster resonance energy transfer (FRET) is performed to show successful lipid mixing. Not only can the device be used to record the dynamics of lipid membrane fusion, but it can be used for reaction monitoring by fusing GUVs containing reactants. We demonstrate this by fusing vesicles encapsulating femtolitre volumes of cobalt chloride or EDTA and monitoring the amount of the complexation product over time.
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Affiliation(s)
- T Robinson
- Department of Chemistry and Applied Biosciences, ETH Zurich, Zurich, 8093, Switzerland.
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5
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Kandušer M, Ušaj M. Cell electrofusion: past and future perspectives for antibody production and cancer cell vaccines. Expert Opin Drug Deliv 2014; 11:1885-98. [DOI: 10.1517/17425247.2014.938632] [Citation(s) in RCA: 28] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/19/2023]
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Terpitz U, Sukhorukov VL, Zimmermann D. Prototype for automatable, dielectrophoretically-accessed intracellular membrane-potential measurements by metal electrodes. Assay Drug Dev Technol 2012; 11:9-16. [PMID: 22994967 DOI: 10.1089/adt.2012.455] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/13/2023] Open
Abstract
Functional access to membrane proteins, for example, ion channels, of individual cells is an important prerequisite in drug discovery studies. The highly sophisticated patch-clamp method is widely used for electrogenic membrane proteins, but is demanding for the operator, and its automation remains challenging. The dielectrophoretically-accessed, intracellular membrane-potential measurement (DAIMM) method is a new technique showing high potential for automation of electrophysiological data recording in the whole-cell configuration. A cell suspension is brought between a mm-scaled planar electrode and a μm-scaled tip electrode, placed opposite to each other. Due to the asymmetric electrode configuration, the application of alternating electric fields (1-5 MHz) provokes a dielectrophoretic force acting on the target cell. As a consequence, the cell is accelerated and pierced by the tip electrode, hence functioning as the internal (working) electrode. We used the light-gated cation channel Channelrhodopsin-2 as a reporter protein expressed in HEK293 cells to characterize the DAIMM method in comparison with the patch-clamp technique.
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Affiliation(s)
- Ulrich Terpitz
- Department of Biophysical Chemistry, Max Planck Institute of Biophysics, Frankfurt am Main, Germany.
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Hu N, Yang J, Qian S, Zhang X, Joo SW, Zheng X. A cell electrofusion microfluidic chip using discrete coplanar vertical sidewall microelectrodes. Electrophoresis 2012; 33:1980-6. [PMID: 22806463 DOI: 10.1002/elps.201100579] [Citation(s) in RCA: 9] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/16/2023]
Abstract
A novel cell electrofusion microfluidic chip using discrete coplanar vertical sidewall electrodes has been designed, fabricated, and tested. The device contains a serpentine-shaped microchannel with 22 500 pairs of vertical sidewall microelectrodes patterned on two opposing vertical sidewalls of the microchannel. The adjacent microelectrodes on each sidewall are separated by coplanar SiO(2) -Polysilicon-SiO(2) /silicon. This design of coplanar discrete vertical sidewall electrodes eliminates the "dead area" present in previous designs using continuous three-dimensional (3D) protruding sidewall electrodes, and generates uniform electric field along the height of the microchannel, leading to a lower voltage required for cell fusion compared to designs using 2D thin-film electrodes. This device is tested to fuse NIH3T3 cells under a low voltage (∼9 V). Almost 100% cells are aligned to the edge of the discrete microelectrodes, and cell-cell pairing efficiency reaches 70%. The electrofusion efficiency is above 40% of the total cells loaded into the device, which is much higher than traditional fusion methods and existing microfluidic devices using continuous 3D protruding sidewall microelectrodes.
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Affiliation(s)
- Ning Hu
- Key Laboratory of Biorheological Science and Technology, Ministry of Education, Key Laboratory for Optoelectronic Technology and Systems, Ministry of Education Chongqing University, Chongqing, P. R. China
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Abstract
Control is intrinsic to biological organisms, whose cells are in a constant state of sensing and response to numerous external and self-generated stimuli. Diverse means are used to study the complexity through control-based approaches in these cellular systems, including through chemical and genetic manipulations, input-output methodologies, feedback approaches, and feed-forward approaches. We first discuss what happens in control-based approaches when we are not actively examining or manipulating cells. We then present potential methods to determine what the cell is doing during these times and to reverse-engineer the cellular system. Finally, we discuss how we can control the cell's extracellular and intracellular environments, both to probe the response of the cells using defined experimental engineering-based technologies and to anticipate what might be achieved by applying control-based approaches to affect cellular processes. Much work remains to apply simplified control models and develop new technologies to aid researchers in studying and utilizing cellular and molecular processes.
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Affiliation(s)
- Philip R LeDuc
- Department of Mechanical Engineering, Carnegie Mellon University, Pittsburgh, PA 15213, USA.
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Development and Prospect of Cell-electrofusion Chip Technology. CHINESE JOURNAL OF ANALYTICAL CHEMISTRY 2012. [DOI: 10.1016/s1872-2040(11)60533-1] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/20/2022]
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Hu N, Yang J, Qian S, Joo SW, Zheng X. A cell electrofusion microfluidic device integrated with 3D thin-film microelectrode arrays. BIOMICROFLUIDICS 2011; 5:34121-3412112. [PMID: 22662046 PMCID: PMC3364834 DOI: 10.1063/1.3630125] [Citation(s) in RCA: 25] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 06/02/2011] [Accepted: 08/03/2011] [Indexed: 05/07/2023]
Abstract
A microfluidic device integrated with 3D thin film microelectrode arrays wrapped around serpentine-shaped microchannel walls has been designed, fabricated and tested for cell electrofusion. Each microelectrode array has 1015 discrete microelectrodes patterned on each side wall, and the adjacent microelectrodes are separated by coplanar dielectric channel wall. The device was tested to electrofuse K562 cells under a relatively low voltage. Under an AC electric field applied between the pair of the microelectrode arrays, cells are paired at the edge of each discrete microelectrode due to the induced positive dielectrophoresis. Subsequently, electric pulse signals are sequentially applied between the microelectrode arrays to induce electroporation and electrofusion. Compared to the design with thin film microelectrode arrays deposited at the bottom of the side walls, the 3D thin film microelectrode array could induce electroporation and electrofusion under a lower voltage. The staggered electrode arrays on opposing side walls induce inhomogeneous electric field distribution, which could avoid multi-cell fusion. The alignment and pairing efficiencies of K562 cells in this device were 99% and 70.7%, respectively. The electric pulse of low voltage (∼9 V) could induce electrofusion of these cells, and the fusion efficiency was about 43.1% of total cells loaded into the device, which is much higher than that of the convectional and most existing microfluidics-based electrofusion devices.
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Hu N, Yang J, Yin ZQ, Ai Y, Qian S, Svir IB, Xia B, Yan JW, Hou WS, Zheng XL. A high-throughput dielectrophoresis-based cell electrofusion microfluidic device. Electrophoresis 2011; 32:2488-95. [PMID: 21853446 DOI: 10.1002/elps.201100082] [Citation(s) in RCA: 25] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/27/2011] [Revised: 04/04/2011] [Accepted: 04/04/2011] [Indexed: 12/17/2022]
Abstract
A high-throughput cell electrofusion microfluidic chip has been designed, fabricated on a silicon-on-insulator wafer and tested for in vitro cell fusion under a low applied voltage. The developed chip consists of six individual straight microchannels with a 40-μm thickness conductive highly doped Si layer as the microchannel wall. In each microchannel, there are 75 pairs of counter protruding microelectrodes, between which the cell electrofusion is performed. The entire highly doped Si layer is covered by a 2-μm thickness aluminum film to maintain a consistent electric field between different protruding microelectrode pairs. A 150-nm thickness SiO₂ film is subsequently deposited on the top face of each protruding microelectrode for better biocompatibility. Owing to the short distance between two counter protruding microelectrodes, a high electric field can be generated for cell electrofusion with a low voltage imposed across the electrodes. Both mammalian cells and plant protoplasts were used to test the cell electrofusion. About 42-68% cells were aligned to form cell-cell pairs by the dielectrophoretic force. After cell alignment, cell pairs were fused to form hybrid cells under the control of cell electroporation and electrofusion signals. The averaged fusion efficiency in the paired cells is above 40% (the highest was about 60%), which is much higher than the traditional polyethylene glycol method (<5%) and traditional electrofusion methods (∼12%). An individual cell electrofusion process could be completed within 10 min, indicating a capability of high throughput.
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Affiliation(s)
- Ning Hu
- Key Laboratory of Biorheological Science and Technology (Chongqing University), Ministry of Education, Bioengineering College, Chongqing University, Chongqing, P. R. China
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Sanges D, Lluis F, Cosma MP. Cell-fusion-mediated reprogramming: pluripotency or transdifferentiation? Implications for regenerative medicine. ADVANCES IN EXPERIMENTAL MEDICINE AND BIOLOGY 2011; 713:137-59. [PMID: 21432018 DOI: 10.1007/978-94-007-0763-4_9] [Citation(s) in RCA: 23] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 12/18/2022]
Abstract
Cell-cell fusion is a natural process that occurs not only during development, but as has emerged over the last few years, also with an important role in tissue regeneration. Interestingly, in-vitro studies have revealed that after fusion of two different cell types, the developmental potential of these cells can change. This suggests that the mechanisms by which cells differentiate during development to acquire their identities is not irreversible, as was considered until a few years ago. To date, it is well established that the fate of a cell can be changed by a process known as reprogramming. This mainly occurs in two different ways: the differentiated state of a cell can be reversed back into a pluripotent state (pluripotent reprogramming), or it can be switched directly to a different differentiated state (lineage reprogramming). In both cases, these possibilities of obtaining sources of autologous somatic cells to maintain, replace or rescue different tissues has provided new and fundamental insights in the stem-cell-therapy field. Most interestingly, the concept that cell reprogramming can also occur in vivo by spontaneous cell fusion events is also emerging, which suggests that this mechanism can be implicated not only in cellular plasticity, but also in tissue regeneration. In this chapter, we will summarize the present knowledge of the molecular mechanisms that mediate the restoration of pluripotency in vitro through cell fusion, as well as the studies carried out over the last 3 decades on lineage reprogramming, both in vitro and in vivo. How the outcome of these studies relate to regenerative medicine applications will also be discussed.
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Affiliation(s)
- Daniela Sanges
- Center for Genomic Regulation (CRG), 08003 Barcelona, Spain.
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Velve-Casquillas G, Le Berre M, Piel M, Tran PT. Microfluidic tools for cell biological research. NANO TODAY 2010; 5:28-47. [PMID: 21152269 PMCID: PMC2998071 DOI: 10.1016/j.nantod.2009.12.001] [Citation(s) in RCA: 207] [Impact Index Per Article: 14.8] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/21/2023]
Abstract
Microfluidic technology is creating powerful tools for cell biologists to control the complete cellular microenvironment, leading to new questions and new discoveries. We review here the basic concepts and methodologies in designing microfluidic devices, and their diverse cell biological applications.
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Affiliation(s)
| | | | | | - Phong T. Tran
- Institut Curie, UMR 144 CNRS, Paris 75005, France
- University of Pennsylvania, Cell and Developmental Biology, Philadelphia, PA 19104, USA
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Le Gac S, van den Berg A. Single cells as experimentation units in lab-on-a-chip devices. Trends Biotechnol 2009; 28:55-62. [PMID: 19914725 DOI: 10.1016/j.tibtech.2009.10.005] [Citation(s) in RCA: 56] [Impact Index Per Article: 3.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/26/2009] [Revised: 10/12/2009] [Accepted: 10/22/2009] [Indexed: 12/12/2022]
Abstract
'Lab-on-a-chip' technology (LOC) has now reached a mature state and is employed commonly in research in the life sciences. LOC devices make novel experimentation possible while providing a sophisticated environment for cellular investigation. As a next step, we introduce here the concept of a 'lab-in-a-cell': the use of a single cell as a minimal and highly confined experimental unit, or experimentation in the simple, but still unequalled, platform provided by nature itself. LOC provides the appropriate format and set of tools for LIC experimentation, and we discuss here three types of LIC investigation: the elucidation of signaling pathways; the creation of novel production units; and the use of microfluidics for assisted reproduction techniques.
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Affiliation(s)
- Séverine Le Gac
- BIOS The Lab-on-a-Chip Group, MESA+ Institute for Nanotechnology, University of Twente, The Netherlands
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HU N, YANG J, ZHENG XL, YIN ZQ, XU HW, ZHANG XG, CAO Y, YANG J, XIA B, XU R, YAN JW, JIANG F. Polyimide Membrane Based Cell-electrofusion Chip. CHINESE JOURNAL OF ANALYTICAL CHEMISTRY 2009. [DOI: 10.1016/s1872-2040(08)60126-7] [Citation(s) in RCA: 17] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/25/2022]
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CAO Y, YANG J, YIN ZQ, HOU WS, ZHENG XL, HU N, YANG J, XU R, ZHANG RQ. Electric Field Simulation of High-throughput Cell Electrofusion Chip. CHINESE JOURNAL OF ANALYTICAL CHEMISTRY 2008. [DOI: 10.1016/s1872-2040(08)60033-x] [Citation(s) in RCA: 10] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 10/22/2022]
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Fukuta K, Kohri K, Fukuda H, Watanabe M, Sugimura T, Nakagama H. Induction of multinucleated cells and apoptosis in the PC-3 prostate cancer cell line by low concentrations of polyethylene glycol 1000. Cancer Sci 2008; 99:1055-62. [PMID: 18380794 PMCID: PMC11159189 DOI: 10.1111/j.1349-7006.2008.00781.x] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022] Open
Abstract
Polyethylene glycol (PEG) has been reported to inhibit the development of colonic lesions in carcinogen-treated rats when administered orally. However, the precise mechanism for the chemopreventive activity of PEG remains largely elusive. Based on a characteristic feature of PEG as a 'fusogen', we investigated its potential as a chemotherapeutic agent through the induction of multinucleated cell formation and apoptosis induction in PC-3 prostate cancer cells. When PC-3 cells were treated with 0.5 and 1.0% PEG 1000, multinucleated cells were induced at a frequency of 8.4 and 13%, respectively, 36 h after PEG treatment under high cell density (1 x 10(6) cells in 100 microL PEG solution) in vitro. Although abnormality of cell cycle progression was not evident in PEG-treated PC-3 cells, multinucleated cells substantially disappeared at around 38 h due to apoptosis. In contrast, no apparent growth suppression was observed when PC-3 cells were exposed to up to 1.0% PEG at a much lower cell density, namely under ordinary culture conditions. Furthermore, injection of 0.5% PEG solution in vivo into PC-3 xenografts implanted in BALB/c-nu/nu male mice significantly suppressed tumor growth compared to phosphate-buffered saline injection. Multinucleated TdT-mediated dUTP-biotin nick end-labeling (TUNEL)-positive cells were observed inside the PEG-injected tumors. PEG was here demonstrated to have anticell proliferation and antitumor effects via induction of apoptosis, possibly by cell fusion. PEG injection therapy could therefore be adopted as an alternative chemotherapeutic strategy for localized prostate cancers, including those that become refractory to androgen-deprivation therapy.
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Affiliation(s)
- Katsuhiro Fukuta
- Biochemistry Division, National Cancer Center Research Institute, 5-1-1, Tsukiji, Chuo-ku, Tokyo 104-0045, Japan
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Zhiqiang Z, Xiaolin Z, Jiangong X, Jianguo C, Jing W, Zhiguo L, Xing W. A 3-d microelectrodes array microchip applied to cell fusion. CONFERENCE PROCEEDINGS : ... ANNUAL INTERNATIONAL CONFERENCE OF THE IEEE ENGINEERING IN MEDICINE AND BIOLOGY SOCIETY. IEEE ENGINEERING IN MEDICINE AND BIOLOGY SOCIETY. ANNUAL CONFERENCE 2007; 2005:1282-5. [PMID: 17282429 DOI: 10.1109/iembs.2005.1616660] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/06/2022]
Abstract
A cell-to-cell fusion technique using 3-D microelectrodes array microchip has been developed. It permits cell-to-cell fusion operation in large amount simultaneously. And it needs much lower voltage (alternating voltage and pulse voltage) than the conventional cell fusion techniques. An array of 16 (4×4) microelectrodes can be fabricated on a 1×1cm silicon wafer. And an experimental system, including circuit control unit, temperature control unit,etc.,has been developed to fuse cells. The alternating voltage is applied to the electrodes makes cells in alignment and in pairs firstly. Dielectrophoresis (DEP) force is used to form cell pairs in the microchip and makes cell pairs contact each other tightly. And then fusion of the cell pairs is induced by electric pulse is applied between electrodes. Microelectrodes of 8μm carbon-fiber are used to test the feasibility of the proposal experimental system, Human hepatocarcinoma SMMC-7721 cells are used as specimens. It's observed that SMMC-7721 cells formed cell pairs and fused successfully.
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Affiliation(s)
- Zhao Zhiqiang
- Key Lab of Biomechanics and Tissue Engineering under the State Education Ministry, Bioenginering College, Chongqing University, 400044, China
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Lynch BP, Hilton AM, Simpson GJ. Nanoscale dielectrophoretic spectroscopy of individual immobilized mammalian blood cells. Biophys J 2006; 91:2678-86. [PMID: 16798803 PMCID: PMC1562388 DOI: 10.1529/biophysj.106.082412] [Citation(s) in RCA: 14] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/06/2006] [Accepted: 05/23/2006] [Indexed: 11/18/2022] Open
Abstract
Dielectrophoretic force microscopy (DEPFM) and spectroscopy have been performed on individual intact surface-immobilized mammalian red blood cells. Dielectrophoretic force spectra were obtained in situ in approximately 125 ms and could be acquired over a region comparable in dimension to the effective diameter of a scanning probe microscopy tip. Good agreement was observed between the measured dielectrophoretic spectra and predictions using a single-shell cell model. In addition to allowing for highly localized dielectric characterization, DEPFM provided a simple means for noncontact imaging of mammalian blood cells under aqueous conditions. These studies demonstrate the feasibility of using DEPFM to monitor localized changes in membrane capacitance in real time with high spatial resolution on immobilized cells, complementing previous studies of mobile whole cells and cell suspensions.
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Affiliation(s)
- Brian P Lynch
- Department of Chemistry, Purdue University, West Lafayette, Indiana 47907, USA
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Estes DJ, Lopez SR, Fuller AO, Mayer M. Triggering and visualizing the aggregation and fusion of lipid membranes in microfluidic chambers. Biophys J 2006; 91:233-43. [PMID: 16617088 PMCID: PMC1479077 DOI: 10.1529/biophysj.105.076398] [Citation(s) in RCA: 41] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/18/2005] [Accepted: 04/05/2006] [Indexed: 11/18/2022] Open
Abstract
We present a method that makes it possible to trigger, observe, and quantify membrane aggregation and fusion of giant liposomes in microfluidic chambers. Using electroformation from spin-coated films of lipids on transparent indium tin oxide electrodes, we formed two-dimensional networks of closely packed, surface-attached giant liposomes. We investigated the effects of fusogenic agents by simply flowing these molecules into the chambers and analyzing the resulting shape changes of more than 100 liposomes in parallel. We used this setup to quantify membrane fusion by several well-studied mechanisms, including fusion triggered by Ca2+, polyethylene glycol, and biospecific tethering. Directly observing many liposomes simultaneously proved particularly useful for studying fusion events in the presence of low concentrations of fusogenic agents, when fusion was rare and probabilistic. We applied this microfluidic fusion assay to investigate a novel 30-mer peptide derived from a recently identified human receptor protein, B5, that is important for membrane fusion during the entry of herpes simplex virus into host cells. This peptide triggered fusion of liposomes at an approximately 6 times higher probability than control peptides and caused irreversible interactions between adjacent membranes; it was, however, less fusogenic than Ca2+ at comparable concentrations. Closely packed, surface-attached giant liposomes in microfluidic chambers offer a method to observe membrane aggregation and fusion in parallel without requiring the use of micromanipulators. This technique makes it possible to characterize rapidly novel fusogenic agents under well-defined conditions.
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Affiliation(s)
- Daniel J Estes
- Department of Biomedical Engineering, College of Engineering, University of Michigan, Ann Arbor, Michigan 48109, USA
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Tan WH, Takeuchi S. Timing controllable electrofusion device for aqueous droplet-based microreactors. LAB ON A CHIP 2006; 6:757-63. [PMID: 16738727 DOI: 10.1039/b517178d] [Citation(s) in RCA: 45] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/09/2023]
Abstract
This paper describes an electrofusion device for controlling the precise moment of fusion between droplets by applying an electric field. This device allows (i) accurate determination of the start of chemical/biological reactions, (ii) minimum contact of reactants with channel walls--eliminating surface absorption problems, (iii) easy fabrication and (iv) continuous observation of initiated reaction. We demonstrated the fusion of beta-galactosidase and fluorescein di-beta-D-galactopyranoside (FDG) droplets, and observed the enzymatic reaction using fluorescence microscopy. In addition, sequential fusion of pico-litre droplets was also accomplished.
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Affiliation(s)
- Wei-Heong Tan
- CIRMM/IIS, Institute of Industrial Science, University of Tokyo, 4-6-1 Komaba, Meguro-ku, Tokyo 153-8505, Japan.
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Park T, Lee M, Choo J, Kim YS, Lee EK, Kim DJ, Lee SH. Analysis of passive mixing behavior in a poly(dimethylsiloxane) microfluidic channel using confocal fluorescence and Raman microscopy. APPLIED SPECTROSCOPY 2004; 58:1172-1179. [PMID: 15527517 DOI: 10.1366/0003702042336019] [Citation(s) in RCA: 17] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/24/2023]
Abstract
Confocal fluorescence microscopy (CFM) and confocal Raman microscopy (CRM) have been applied to monitor the laminar flow mixing behavior in a poly(dimethylsiloxane) (PDMS) microfluidic channel. Two passive PDMS micromixing devices were fabricated for this purpose: a two-dimensional round-wave channel and a three-dimensional serpentine channel. The microscale laminar flow mixing of ethanol and isopropanol was evaluated using the CFM and CRM at various flow rates. The mixing behavior of confluent streams in the microchannel was assessed by determining the degree of color change in Rhodamine 6G dye on mixing using the CFM. However, it was also possible to quantitatively evaluate the mixing process without employing a fluorescence label using the CRM. The results show a strong potential for CRM as a highly sensitive detection tool to measure fundamental fluid mixing processes and to provide detailed information on chemical changes of non-fluorescent reaction mixtures in a PDMS microfluidic channel.
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Affiliation(s)
- Taehan Park
- Department of Chemistry, Hanyang University, Ansan 426-791, Korea
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Abstract
Electroporation is a widely used method for the introduction of polar and charged agents such as dyes, drugs, DNA, RNA, proteins, peptides, and amino acids into cells. Traditionally, electroporation is performed with large electrodes in a batch mode for treatment of a large number of cells in suspension. Recently, microelectrodes that can produce extremely localized electric fields, such as solid carbon fiber microelectrodes, electrolyte-filled capillaries and micropipettes as well as chip-based microfabricated electrode arrays, have proven useful to electroporate single cells and subcellular structures. Single-cell electroporation opens up a new window of opportunities in manipulating the genetic, metabolic, and synthetic contents of single targeted cells in tissue slices, cell cultures, in microfluidic channels or at specific loci on a chip-based device.
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Affiliation(s)
- Jessica Olofsson
- Department of Physical Chemistry and Microtechnology Centre, Chalmers, SE-412 96, Göteborg, Sweden
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Abstract
Technological advances in miniaturization have found a niche in biology and signal the beginning of a new revolution. Most of the attention and advances have been made with DNA chips yet a lot of progress is being made in the use of other biomolecules and cells. A variety of reviews have covered only different aspects and technologies but leading to the shared terminology of "biochips." This review provides a basic introduction and an in-depth survey of the different technologies and applications involving the use of non-DNA molecules such as proteins and cells. The review focuses on microarrays and microfluidics, but also describes some cellular systems (studies involving patterning and sensor chips) and nanotechnology. The principles of each technology including parameters involved in biochip design and operation are outlined. A discussion of the different biological and biomedical applications illustrates the significance of biochips in biotechnology.
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Affiliation(s)
- Jocelyn H Ng
- IMI Consulting GmbH, Auf dem Amtshof 3, 30938 Burgwedel, Germany.
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Affiliation(s)
- Deirdre R Meldrum
- Genomation Laboratory, Department of Electrical Engineering, University of Washington, Seattle, WA 98195-2500, USA.
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Khandurina J, Guttman A. Microchip-based high-throughput screening analysis of combinatorial libraries. Curr Opin Chem Biol 2002; 6:359-66. [PMID: 12968633 DOI: 10.1016/s1367-5931(02)00323-x] [Citation(s) in RCA: 66] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Abstract
In recent years, there have been significant advances in biochemical assay miniturization and integration of microchip-based technologies with combinatorial library screening for high-throughput and large-scale applications. Small-molecule microarrays, protein arrays and cell-based arrays and conventional DNA arrays as well as microfluidic approaches in HTS are discussed in this review.
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Affiliation(s)
- Julia Khandurina
- Torrey Mesa Research Institute, 3115 Merryfield Row, San Diego, CA 92121, USA
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