1
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Leong LM, Storace DA. Imaging different cell populations in the mouse olfactory bulb using the genetically encoded voltage indicator ArcLight. NEUROPHOTONICS 2024; 11:033402. [PMID: 38288247 PMCID: PMC10823906 DOI: 10.1117/1.nph.11.3.033402] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Figures] [Subscribe] [Scholar Register] [Received: 09/01/2023] [Revised: 11/30/2023] [Accepted: 12/14/2023] [Indexed: 01/31/2024]
Abstract
Genetically encoded voltage indicators (GEVIs) are protein-based optical sensors that allow for measurements from genetically defined populations of neurons. Although in vivo imaging in the mammalian brain with early generation GEVIs was difficult due to poor membrane expression and low signal-to-noise ratio, newer and more sensitive GEVIs have begun to make them useful for answering fundamental questions in neuroscience. We discuss principles of imaging using GEVIs and genetically encoded calcium indicators, both useful tools for in vivo imaging of neuronal activity, and review some of the recent mechanistic advances that have led to GEVI improvements. We provide an overview of the mouse olfactory bulb (OB) and discuss recent studies using the GEVI ArcLight to study different cell types within the bulb using both widefield and two-photon microscopy. Specific emphasis is placed on using GEVIs to begin to study the principles of concentration coding in the OB, how to interpret the optical signals from population measurements in the in vivo brain, and future developments that will push the field forward.
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Affiliation(s)
- Lee Min Leong
- Florida State University, Department of Biological Science, Tallahassee, Florida, United States
| | - Douglas A. Storace
- Florida State University, Department of Biological Science, Tallahassee, Florida, United States
- Florida State University, Program in Neuroscience, Tallahassee, Florida, United States
- Florida State University, Institute of Molecular Biophysics, Tallahassee, Florida, United States
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2
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Sözer EB, Semenov I, Thomas Vernier P. Dihydroethidium-derived fluorescence in electrically stressed cells indicates intracellular microenvironment modifications independent of ROS. Bioelectrochemistry 2024; 160:108751. [PMID: 38851174 DOI: 10.1016/j.bioelechem.2024.108751] [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: 01/03/2024] [Revised: 05/15/2024] [Accepted: 05/27/2024] [Indexed: 06/10/2024]
Abstract
Intracellular reactive oxygen species (ROS) generation is widely suggested as a trigger for biological consequences of electric field exposures, such as those in electroporation applications. ROS are linked with membrane barrier function degradation, genetic damage, and complex events like immunological cell death. Dihydroethidium (DHE) is commonly used to monitor ROS in cells. DHE is linked to intracellular ROS by a primary oxidation product, Ethidium (Eth+), that shows increased fluorescence upon binding to polynucleotides. We observed changes in DHE-derived fluorescence in Chinese hamster ovary (CHO) cells post 300-ns electric pulse exposures, comparing them to tert-butyl-hydroperoxide (t-BHP) induced oxidative stress. Immediate intracellular fluorescence changes were noted in both cases, but with distinct localization patterns. After electrical stress, cytosolic DHE-derived fluorescence intensity decreases, and nucleolar intensity increases. Conversely, t-BHP exposure increases DHE-derived fluorescence uniformly across the cell. Surprisingly, fluorescence patterns after electrical stress in Eth+-loaded cells is identical to those in DHE-loaded cells, in kinetics and localization patterns. These findings indicate that DHE-derived fluorescence changes after pulsed electric field stress are not due to intracellular ROS generation leading to DHE oxidation, but rather indicate stress-induced intracellular microenvironment alterations affecting Eth+ fluorescence.
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Affiliation(s)
- Esin B Sözer
- Old Dominion University, Frank Reidy Research Center for Bioelectrics, Norfolk, VA, USA.
| | - Iurii Semenov
- Old Dominion University, Frank Reidy Research Center for Bioelectrics, Norfolk, VA, USA
| | - P Thomas Vernier
- Old Dominion University, Frank Reidy Research Center for Bioelectrics, Norfolk, VA, USA.
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3
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Milan HFM, Almazloum AA, Bassani RA, Bassani JWM. Membrane polarization at the excitation threshold induced by external electric fields in cardiomyocytes of rats at different developmental stages. Med Biol Eng Comput 2023; 61:2637-2647. [PMID: 37405671 DOI: 10.1007/s11517-023-02868-1] [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: 02/03/2023] [Accepted: 06/07/2023] [Indexed: 07/06/2023]
Abstract
External electric fields (E), used for cardiac pacing and defibrillation/cardioversion, induce a spatially variable change in cardiomyocyte transmembrane potential (ΔVm) that depends on cell geometry and E orientation. This study investigates E-induced ΔVm in cardiomyocytes from rats at different ages, which show marked size/geometry variation. Using a tridimensional numerical electromagnetic model recently proposed (NM3D), it was possible: (a) to evaluate the suitability of the simpler, prolate spheroid analytical model (PSAM) to calculate amplitude and location of ΔVm maximum (ΔVmax) for E = 1 V.cm-1; and (b) to estimate the ΔVmax required for excitation (ΔVT) from experimentally determined threshold E values (ET). Ventricular myocytes were isolated from neonatal, weaning, adult, and aging Wistar rats. NM3D was constructed as the extruded 2D microscopy cell image, while measured minor and major cell dimensions were used for PSAM. Acceptable ΔVm estimates can be obtained with PSAM from paralelepidal cells for small θ. ET, but not ΔVT, was higher for neonate cells. ΔVT was significantly greater in the cell from older animals, which indicate lower responsiveness to E associated with aging, rather than with altered cell geometry/dimensions. ΔVT might be used as a non-invasive indicator of cell excitability as it is little affected by cell geometry/size.
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Affiliation(s)
- Hugo F M Milan
- Department of Electronics and Biomedical Engineering, School of Electrical and Computer Engineering, University of Campinas (UNICAMP), Cidade Universitária Zeferino Vaz, Av. Albert Einstein 400, Campinas, SP, 13083-852, Brazil.
| | - Ahmad A Almazloum
- Department of Electronics and Biomedical Engineering, School of Electrical and Computer Engineering, University of Campinas (UNICAMP), Cidade Universitária Zeferino Vaz, Av. Albert Einstein 400, Campinas, SP, 13083-852, Brazil
| | - Rosana A Bassani
- Department of Electronics and Biomedical Engineering, School of Electrical and Computer Engineering, University of Campinas (UNICAMP), Cidade Universitária Zeferino Vaz, Av. Albert Einstein 400, Campinas, SP, 13083-852, Brazil
- LabNECC, Center for Biomedical Engineering (CEB), University of Campinas (UNICAMP), R. Alexander Fleming 163, Cidade Universitária Zeferino Vaz, Campinas, SP, 13083-881, Brazil
| | - José W M Bassani
- Department of Electronics and Biomedical Engineering, School of Electrical and Computer Engineering, University of Campinas (UNICAMP), Cidade Universitária Zeferino Vaz, Av. Albert Einstein 400, Campinas, SP, 13083-852, Brazil
- LabNECC, Center for Biomedical Engineering (CEB), University of Campinas (UNICAMP), R. Alexander Fleming 163, Cidade Universitária Zeferino Vaz, Campinas, SP, 13083-881, Brazil
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4
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Ruiz-Fernández AR, Campos L, Villanelo F, Garate JA, Perez-Acle T. Protein-Mediated Electroporation in a Cardiac Voltage-Sensing Domain Due to an nsPEF Stimulus. Int J Mol Sci 2023; 24:11397. [PMID: 37511161 PMCID: PMC10379607 DOI: 10.3390/ijms241411397] [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: 04/29/2023] [Revised: 06/15/2023] [Accepted: 07/05/2023] [Indexed: 07/30/2023] Open
Abstract
This study takes a step in understanding the physiological implications of the nanosecond pulsed electric field (nsPEF) by integrating molecular dynamics simulations and machine learning techniques. nsPEF, a state-of-the-art technology, uses high-voltage electric field pulses with a nanosecond duration to modulate cellular activity. This investigation reveals a relatively new and underexplored phenomenon: protein-mediated electroporation. Our research focused on the voltage-sensing domain (VSD) of the NaV1.5 sodium cardiac channel in response to nsPEF stimulation. We scrutinized the VSD structures that form pores and thereby contribute to the physical chemistry that governs the defibrillation effect of nsPEF. To do so, we conducted a comprehensive analysis involving the clustering of 142 replicas simulated for 50 ns under nsPEF stimuli. We subsequently pinpointed the representative structures of each cluster and computed the free energy between them. We find that the selected VSD of NaV1.5 forms pores under nsPEF stimulation, but in a way that significant differs from the traditional VSD opening. This study not only extends our understanding of nsPEF and its interaction with protein channels but also adds a new effect to further study.
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Affiliation(s)
| | - Leonardo Campos
- Computational Biology Lab, Fundación Ciencia & Vida, Santiago 7780272, Chile
- Facultad de Ingeniería y Tecnología, Universidad San Sebastián, Santiago 8420524, Chile
| | - Felipe Villanelo
- Computational Biology Lab, Fundación Ciencia & Vida, Santiago 7780272, Chile
- Facultad de Ingeniería y Tecnología, Universidad San Sebastián, Santiago 8420524, Chile
| | - Jose Antonio Garate
- Computational Biology Lab, Fundación Ciencia & Vida, Santiago 7780272, Chile
- Facultad de Ingeniería y Tecnología, Universidad San Sebastián, Santiago 8420524, Chile
- Millennium Nucleus im NanoBioPhysics, Universidad de Valparaiso, Valparaiso 2351319, Chile
| | - Tomas Perez-Acle
- Computational Biology Lab, Fundación Ciencia & Vida, Santiago 7780272, Chile
- Facultad de Ingeniería y Tecnología, Universidad San Sebastián, Santiago 8420524, Chile
- Centro Interdisciplinario de Neurociencia de Valparaíso, Universidad de Valparaíso, Valparaiso 2360102, Chile
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5
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Guedert R, Brasil Pintarelli G, Mena Barreto Silva FR, Ota Hisayasu Suzuki D. Effects of pulse repetition rate in static electrochemotherapy models. Bioelectrochemistry 2023; 153:108499. [PMID: 37413821 DOI: 10.1016/j.bioelechem.2023.108499] [Citation(s) in RCA: 1] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/03/2023] [Revised: 06/28/2023] [Accepted: 06/29/2023] [Indexed: 07/08/2023]
Abstract
Electroporation alters cell membrane structure and tissue electrical properties by short and intense pulsed electric fields (PEF). Static mathematical models are often used to explain the change in electrical properties of tissues caused by electroporation. Electric pulse repetition rate may play an important role, as tissue dielectric dispersion, electroporation dynamics, and Joule heating may affect the electrical properties. In this work, we investigate the effects on the magnitude of the electric current when the repetition rate of the standard electrochemotherapy protocol is increased. Liver, oral mucosa, and muscle tissues were studied. Ex vivo animal experiments show that the magnitude of the electric current increases when the repetition rate is changed from 1 Hz to 5 kHz (10.8% for liver, 5.8% for oral mucosa, and 4.7% for muscle). Although a correction factor could reduce the error to less than 1%, dynamic models seem to be necessary to analyze different protocol signatures. Authors should be aware that static models and experimental results can only be compared if they use exactly the same PEF signature. The repetition rate is a key information to consider in the pretreatment computer study because the current at 1 Hz PEF differs from a 5 kHz PEF.
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Affiliation(s)
- Raul Guedert
- Institute of Biomedical Engineering, Federal University of Santa Catarina, Florianópolis, SC, Brazil.
| | - Guilherme Brasil Pintarelli
- Department of Control and Automation Engineering, Federal University of Santa Catarina, Blumenau, SC, Brazil.
| | - Fátima Regina Mena Barreto Silva
- Hormone and Signals Transduction Laboratory, Núcleo de Bioeletricidade Celular (NUBIOCEL), Departamento de Bioquímica, Center of Biological Sciences, Federal University of Santa Catarina, Florianópolis, SC, Brazil.
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6
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Aseyev N, Ivanova V, Balaban P, Nikitin E. Current Practice in Using Voltage Imaging to Record Fast Neuronal Activity: Successful Examples from Invertebrate to Mammalian Studies. BIOSENSORS 2023; 13:648. [PMID: 37367013 DOI: 10.3390/bios13060648] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 05/17/2023] [Revised: 06/09/2023] [Accepted: 06/12/2023] [Indexed: 06/28/2023]
Abstract
The optical imaging of neuronal activity with potentiometric probes has been credited with being able to address key questions in neuroscience via the simultaneous recording of many neurons. This technique, which was pioneered 50 years ago, has allowed researchers to study the dynamics of neural activity, from tiny subthreshold synaptic events in the axon and dendrites at the subcellular level to the fluctuation of field potentials and how they spread across large areas of the brain. Initially, synthetic voltage-sensitive dyes (VSDs) were applied directly to brain tissue via staining, but recent advances in transgenic methods now allow the expression of genetically encoded voltage indicators (GEVIs), specifically in selected neuron types. However, voltage imaging is technically difficult and limited by several methodological constraints that determine its applicability in a given type of experiment. The prevalence of this method is far from being comparable to patch clamp voltage recording or similar routine methods in neuroscience research. There are more than twice as many studies on VSDs as there are on GEVIs. As can be seen from the majority of the papers, most of them are either methodological ones or reviews. However, potentiometric imaging is able to address key questions in neuroscience by recording most or many neurons simultaneously, thus providing unique information that cannot be obtained via other methods. Different types of optical voltage indicators have their advantages and limitations, which we focus on in detail. Here, we summarize the experience of the scientific community in the application of voltage imaging and try to evaluate the contribution of this method to neuroscience research.
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Affiliation(s)
- Nikolay Aseyev
- Institute of Higher Nervous Activity and Neurophysiology, Russian Academy of Sciences, Butlerova 5A, Moscow 117485, Russia
| | - Violetta Ivanova
- Institute of Higher Nervous Activity and Neurophysiology, Russian Academy of Sciences, Butlerova 5A, Moscow 117485, Russia
| | - Pavel Balaban
- Institute of Higher Nervous Activity and Neurophysiology, Russian Academy of Sciences, Butlerova 5A, Moscow 117485, Russia
| | - Evgeny Nikitin
- Institute of Higher Nervous Activity and Neurophysiology, Russian Academy of Sciences, Butlerova 5A, Moscow 117485, Russia
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7
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Ibrahimi N, Vallet L, Andre FM, Rivaletto M, Novac BM, Mir LM, Pécastaing L. An Overview of Subnanosecond Pulsed Electric Field Biological Effects: Toward Contactless Technologies for Cancer Treatment. Bioelectricity 2023. [DOI: 10.1089/bioe.2022.0031] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 04/07/2023] Open
Affiliation(s)
- Njomza Ibrahimi
- Laboratoire des Sciences de l'Ingénieur Appliquées à la Mécanique et au Génie Électrique–Fédération IPRA, EA4581, Université de Pau et des Pays de l'Adour/E2S UPPA, Pau, France
| | - Leslie Vallet
- Université Paris-Saclay, CNRS, Gustave Roussy, UMR 9018, Metabolic and Systemic Aspects of Oncogenesis (METSY), Villejuif, France
| | - Franck M. Andre
- Université Paris-Saclay, CNRS, Gustave Roussy, UMR 9018, Metabolic and Systemic Aspects of Oncogenesis (METSY), Villejuif, France
| | - Marc Rivaletto
- Laboratoire des Sciences de l'Ingénieur Appliquées à la Mécanique et au Génie Électrique–Fédération IPRA, EA4581, Université de Pau et des Pays de l'Adour/E2S UPPA, Pau, France
| | - Bucur M. Novac
- Laboratoire des Sciences de l'Ingénieur Appliquées à la Mécanique et au Génie Électrique–Fédération IPRA, EA4581, Université de Pau et des Pays de l'Adour/E2S UPPA, Pau, France
- Wolfson School of Mechanical, Electrical and Manufacturing Engineering, Loughborough University, Loughborough, United Kingdom
| | - Lluis M. Mir
- Université Paris-Saclay, CNRS, Gustave Roussy, UMR 9018, Metabolic and Systemic Aspects of Oncogenesis (METSY), Villejuif, France
| | - Laurent Pécastaing
- Laboratoire des Sciences de l'Ingénieur Appliquées à la Mécanique et au Génie Électrique–Fédération IPRA, EA4581, Université de Pau et des Pays de l'Adour/E2S UPPA, Pau, France
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8
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Zare F, Ghasemi N, Bansal N, Hosano H. Advances in pulsed electric stimuli as a physical method for treating liquid foods. Phys Life Rev 2023; 44:207-266. [PMID: 36791571 DOI: 10.1016/j.plrev.2023.01.007] [Citation(s) in RCA: 8] [Impact Index Per Article: 8.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/24/2023] [Accepted: 01/28/2023] [Indexed: 02/05/2023]
Abstract
There is a need for alternative technologies that can deliver safe and nutritious foods at lower costs as compared to conventional processes. Pulsed electric field (PEF) technology has been utilised for a plethora of different applications in the life and physical sciences, such as gene/drug delivery in medicine and extraction of bioactive compounds in food science and technology. PEF technology for treating liquid foods involves engineering principles to develop the equipment, and quantitative biochemistry and microbiology techniques to validate the process. There are numerous challenges to address for its application in liquid foods such as the 5-log pathogen reduction target in food safety, maintaining the food quality, and scale up of this physical approach for industrial integration. Here, we present the engineering principles associated with pulsed electric fields, related inactivation models of microorganisms, electroporation and electropermeabilization theory, to increase the quality and safety of liquid foods; including water, milk, beer, wine, fruit juices, cider, and liquid eggs. Ultimately, we discuss the outlook of the field and emphasise research gaps.
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Affiliation(s)
- Farzan Zare
- School of Information Technology and Electrical Engineering, The University of Queensland, Brisbane, St Lucia QLD 4072, Australia; School of Agriculture and Food Sciences, The University of Queensland, St Lucia QLD 4072, Australia
| | - Negareh Ghasemi
- School of Information Technology and Electrical Engineering, The University of Queensland, Brisbane, St Lucia QLD 4072, Australia
| | - Nidhi Bansal
- School of Agriculture and Food Sciences, The University of Queensland, St Lucia QLD 4072, Australia
| | - Hamid Hosano
- Biomaterials and Bioelectrics Department, Institute of Industrial Nanomaterials, Kumamoto University, Kumamoto 860-8555, Japan.
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9
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Radzevičiūtė E, Malyško-Ptašinskė V, Kulbacka J, Rembiałkowska N, Novickij J, Girkontaitė I, Novickij V. Nanosecond electrochemotherapy using bleomycin or doxorubicin: Influence of pulse amplitude, duration and burst frequency. Bioelectrochemistry 2022; 148:108251. [DOI: 10.1016/j.bioelechem.2022.108251] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/20/2022] [Revised: 07/08/2022] [Accepted: 08/21/2022] [Indexed: 11/02/2022]
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10
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Rems L, Tang X, Zhao F, Pérez-Conesa S, Testa I, Delemotte L. Identification of electroporation sites in the complex lipid organization of the plasma membrane. eLife 2022; 11:e74773. [PMID: 35195069 PMCID: PMC8912918 DOI: 10.7554/elife.74773] [Citation(s) in RCA: 7] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/16/2021] [Accepted: 02/22/2022] [Indexed: 11/13/2022] Open
Abstract
The plasma membrane of a biological cell is a complex assembly of lipids and membrane proteins, which tightly regulate transmembrane transport. When a cell is exposed to strong electric field, the membrane integrity becomes transiently disrupted by formation of transmembrane pores. This phenomenon termed electroporation is already utilized in many rapidly developing applications in medicine including gene therapy, cancer treatment, and treatment of cardiac arrhythmias. However, the molecular mechanisms of electroporation are not yet sufficiently well understood; in particular, it is unclear where exactly pores form in the complex organization of the plasma membrane. In this study, we combine coarse-grained molecular dynamics simulations, machine learning methods, and Bayesian survival analysis to identify how formation of pores depends on the local lipid organization. We show that pores do not form homogeneously across the membrane, but colocalize with domains that have specific features, the most important being high density of polyunsaturated lipids. We further show that knowing the lipid organization is sufficient to reliably predict poration sites with machine learning. Additionally, by analysing poration kinetics with Bayesian survival analysis we show that poration does not depend solely on local lipid arrangement, but also on membrane mechanical properties and the polarity of the electric field. Finally, we discuss how the combination of atomistic and coarse-grained molecular dynamics simulations, machine learning methods, and Bayesian survival analysis can guide the design of future experiments and help us to develop an accurate description of plasma membrane electroporation on the whole-cell level. Achieving this will allow us to shift the optimization of electroporation applications from blind trial-and-error approaches to mechanistic-driven design.
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Affiliation(s)
- Lea Rems
- KTH Royal Institute of Technology, Dept. Applied Physics, Science for Life LaboratorySolnaSweden
- University of Ljubljana, Faculty of Electrical EngineeringLjubljanaSlovenia
| | - Xinru Tang
- KTH Royal Institute of Technology, Dept. Applied Physics, Science for Life LaboratorySolnaSweden
- University of Chinese Academy of SciencesBeijingChina
| | - Fangwei Zhao
- KTH Royal Institute of Technology, Dept. Applied Physics, Science for Life LaboratorySolnaSweden
- University of Chinese Academy of SciencesBeijingChina
| | - Sergio Pérez-Conesa
- KTH Royal Institute of Technology, Dept. Applied Physics, Science for Life LaboratorySolnaSweden
| | - Ilaria Testa
- KTH Royal Institute of Technology, Dept. Applied Physics, Science for Life LaboratorySolnaSweden
| | - Lucie Delemotte
- KTH Royal Institute of Technology, Dept. Applied Physics, Science for Life LaboratorySolnaSweden
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11
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Ahamed MK, Ahmed M, Karal MAS. Quantification of pulsed electric field for the rupture of giant vesicles with various surface charges, cholesterols and osmotic pressures. PLoS One 2022; 17:e0262555. [PMID: 35025973 PMCID: PMC8757908 DOI: 10.1371/journal.pone.0262555] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/01/2021] [Accepted: 12/28/2021] [Indexed: 12/02/2022] Open
Abstract
Electropermeabilization is a promising phenomenon that occurs when pulsed electric field with high frequency is applied to cells/vesicles. We quantify the required values of pulsed electric fields for the rupture of cell-sized giant unilamellar vesicles (GUVs) which are prepared under various surface charges, cholesterol contents and osmotic pressures. The probability of rupture and the average time of rupture are evaluated under these conditions. The electric field changes from 500 to 410 Vcm-1 by varying the anionic lipid mole fraction from 0 to 0.60 for getting the maximum probability of rupture (i.e., 1.0). In contrast, the same probability of rupture is obtained for changing the electric field from 410 to 630 Vcm-1 by varying the cholesterol mole fraction in the membranes from 0 to 0.40. These results suggest that the required electric field for the rupture decreases with the increase of surface charge density but increases with the increase of cholesterol. We also quantify the electric field for the rupture of GUVs containing anionic mole fraction of 0.40 under various osmotic pressures. In the absence of osmotic pressure, the electric field for the rupture is obtained 430 Vcm-1, whereas the field is 300 Vcm-1 in the presence of 17 mOsmL-1, indicating the instability of GUVs at higher osmotic pressures. These investigations open an avenue of possibilities for finding the electric field dependent rupture of cell-like vesicles along with the insight of biophysical and biochemical processes.
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Affiliation(s)
- Md. Kabir Ahamed
- Department of Physics, Bangladesh University of Engineering and Technology, Dhaka, Bangladesh
| | - Marzuk Ahmed
- Department of Physics, Bangladesh University of Engineering and Technology, Dhaka, Bangladesh
| | - Mohammad Abu Sayem Karal
- Department of Physics, Bangladesh University of Engineering and Technology, Dhaka, Bangladesh
- * E-mail:
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12
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Lee D, Chan SSY, Aksic N, Bajalovic N, Loke DK. Ultralong-Time Recovery and Low-Voltage Electroporation for Biological Cell Monitoring Enabled by a Microsized Multipulse Framework. ACS OMEGA 2021; 6:35325-35333. [PMID: 34984264 PMCID: PMC8717367 DOI: 10.1021/acsomega.1c04257] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 08/09/2021] [Accepted: 10/20/2021] [Indexed: 05/05/2023]
Abstract
Long-term nondestructive monitoring of cells is of significant importance for understanding cell proliferation, cell signaling, cell death, and other processes. However, traditional monitoring methods are limited to a certain range of testing conditions and may reduce cell viability. Here, we present a microgap, multishot electroporation (M2E) system for monitoring cell recovery for up to ∼2 h using ∼5 V pulses and with excellent cell viability using a medium cell population. Electric field simulations reveal the bias-voltage- and gap-size-dependent electric field intensities in the M2E system. In addition to excellent transparency with low cell toxicity, the M2E system does not require specialized components, expensive materials, complicated fabrication processes, or cell manipulations; it just consists of a micrometer-sized pattern and a low-voltage square-wave generator. Ultimately, the M2E system can offer a long-term and nontoxic method of cell monitoring.
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Affiliation(s)
- Denise Lee
- Department
of Science, Mathematics and Technology, Singapore University of Technology and Design, Singapore 487372, Singapore
| | - Sophia S. Y. Chan
- Department
of Science, Mathematics and Technology, Singapore University of Technology and Design, Singapore 487372, Singapore
| | - Nemanja Aksic
- Department
of Science, Mathematics and Technology, Singapore University of Technology and Design, Singapore 487372, Singapore
| | - Natasa Bajalovic
- Department
of Science, Mathematics and Technology, Singapore University of Technology and Design, Singapore 487372, Singapore
| | - Desmond K. Loke
- Department
of Science, Mathematics and Technology, Singapore University of Technology and Design, Singapore 487372, Singapore
- Office
of Innovation, Changi General Hospital, Singapore 529889, Singapore
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13
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Pulse Duration Dependent Asymmetry in Molecular Transmembrane Transport Due to Electroporation in H9c2 Rat Cardiac Myoblast Cells In Vitro. Molecules 2021; 26:molecules26216571. [PMID: 34770979 PMCID: PMC8588460 DOI: 10.3390/molecules26216571] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/03/2021] [Revised: 10/09/2021] [Accepted: 10/22/2021] [Indexed: 11/17/2022] Open
Abstract
Electroporation (EP) is one of the successful physical methods for intracellular drug delivery, which temporarily permeabilizes plasma membrane by exposing cells to electric pulses. Orientation of cells in electric field is important for electroporation and, consequently, for transport of molecules through permeabilized plasma membrane. Uptake of molecules after electroporation are the greatest at poles of cells facing electrodes and is often asymmetrical. However, asymmetry reported was inconsistent and inconclusive-in different reports it was either preferentially anodal or cathodal. We investigated the asymmetry of polar uptake of calcium ions after electroporation with electric pulses of different durations, as the orientation of elongated cells affects electroporation to a different extent when using electric pulses of different durations in the range of 100 ns to 100 µs. The results show that with 1, 10, and 100 µs pulses, the uptake of calcium ions is greater at the pole closer to the cathode than at the pole closer to the anode. With shorter 100 ns pulses, the asymmetry is not observed. A different extent of electroporation at different parts of elongated cells, such as muscle or cardiac cells, may have an impact on electroporation-based treatments such as drug delivery, pulse-field ablation, and gene electrotransfection.
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14
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Kiester AS, Ibey BL, Coker ZN, Pakhomov AG, Bixler JN. Strobe photography mapping of cell membrane potential with nanosecond resolution. Bioelectrochemistry 2021; 142:107929. [PMID: 34438186 DOI: 10.1016/j.bioelechem.2021.107929] [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: 10/01/2020] [Revised: 08/07/2021] [Accepted: 08/10/2021] [Indexed: 10/20/2022]
Abstract
The ability to directly observe membrane potential charging dynamics across a full microscopic field of view is vital for understanding interactions between a biological system and a given electrical stimulus. Accurate empirical knowledge of cell membrane electrodynamics will enable validation of fundamental hypotheses posited by the single shell model, which includes the degree of voltage change across a membrane and cellular sensitivity to external electric field non-uniformity and directionality. To this end, we have developed a high-speed strobe microscopy system with a time resolution of ~ 6 ns that allows us to acquire time-sequential data for temporally repeatable events (non-injurious electrostimulation). The imagery from this system allows for direct comparison of membrane voltage change to both computationally simulated external electric fields and time-dependent membrane charging models. Acquisition of a full microscope field of view enables the selection of data from multiple cell locations experiencing different electrical fields in a single image sequence for analysis. Using this system, more realistic membrane parameters can be estimated from living cells to better inform predictive models. As a proof of concept, we present evidence that within the range of membrane conductivity used in simulation literature, higher values are likely more valid.
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Affiliation(s)
- Allen S Kiester
- Bioeffects Division, Airman System Directorate, 711th Human Performance Wing, Air Force Research Laboratory, JBSA Fort Sam Houston, TX, USA
| | - Bennett L Ibey
- Bioeffects Division, Airman System Directorate, 711th Human Performance Wing, Air Force Research Laboratory, JBSA Fort Sam Houston, TX, USA
| | | | - Andrei G Pakhomov
- Frank Reidy Research Center for Bioelectrics, Old Dominion University, Norfolk, VA, USA
| | - Joel N Bixler
- Bioeffects Division, Airman System Directorate, 711th Human Performance Wing, Air Force Research Laboratory, JBSA Fort Sam Houston, TX, USA.
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15
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Kiełbik A, Szlasa W, Novickij V, Szewczyk A, Maciejewska M, Saczko J, Kulbacka J. Effects of high-frequency nanosecond pulses on prostate cancer cells. Sci Rep 2021; 11:15835. [PMID: 34349171 PMCID: PMC8339066 DOI: 10.1038/s41598-021-95180-7] [Citation(s) in RCA: 10] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/27/2021] [Accepted: 07/21/2021] [Indexed: 02/07/2023] Open
Abstract
Electroporation with pulsed electric fields show a potential to be applied as an experimental focal therapy of tumors. Sub-microsecond regime of electric pulses displays unique electrophysical features operative in cells and membranes. Recently, MHz compression of nanosecond pulses electric fields (nsPEFs) bursts proved to enhance the effectiveness of the therapy. High morbidity of prostate cancer (PCa) and risk of overtreatment associated with this malignancy call for new minimal-invasive treatment alternative. Herein we present the in vitro study for developing applications based on this new technology. In this study, we used flow cytometric analysis, cell viability assay, caspase activity analysis, wound healing assay, confocal microscopy study, and immunofluorescence to investigate the biological effect of high-frequency nsPEFs on PCa cells. Our results show that high-frequency nsPEFs induces the permeabilization and cell death of PCa cells. The cytotoxicity is significantly enhanced in MHz compression of pulses and with the presence of extracellular Ca2+. High-frequency nsPEFs trigger changes in PCa cells' cytoskeleton and their mobility. The presented data show a therapeutic potential of high-frequency nsPEFs in a PCa setting. The sub-microsecond regime of pulses can potentially be applied in nanosecond electroporation protocols for PCa treatment.
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Affiliation(s)
- Aleksander Kiełbik
- grid.4495.c0000 0001 1090 049XMedical University Hospital, Borowska 213, 50-556 Wrocław, Poland ,grid.4495.c0000 0001 1090 049XDepartment of Molecular and Cellular Biology, Faculty of Pharmacy, Wroclaw Medical University, Wrocław, Poland
| | - Wojciech Szlasa
- grid.4495.c0000 0001 1090 049XFaculty of Medicine, Wroclaw Medical University, Wrocław, Poland
| | - Vitalij Novickij
- grid.9424.b0000 0004 1937 1776Institute of High Magnetic Fields, Vilnius Gediminas Technical University, Vilnius, Lithuania
| | - Anna Szewczyk
- grid.4495.c0000 0001 1090 049XDepartment of Molecular and Cellular Biology, Faculty of Pharmacy, Wroclaw Medical University, Wrocław, Poland ,grid.8505.80000 0001 1010 5103Department of Animal Developmental Biology, Institute of Experimental Biology, University of Wroclaw, 50-328 Wrocław, Poland
| | - Magdalena Maciejewska
- grid.413454.30000 0001 1958 0162Hirszfeld Institute of Immunology and Experimental Therapy, Polish Academy of Sciences, 53-114 Wrocław, Poland
| | - Jolanta Saczko
- grid.4495.c0000 0001 1090 049XDepartment of Molecular and Cellular Biology, Faculty of Pharmacy, Wroclaw Medical University, Wrocław, Poland
| | - Julita Kulbacka
- grid.4495.c0000 0001 1090 049XDepartment of Molecular and Cellular Biology, Faculty of Pharmacy, Wroclaw Medical University, Wrocław, Poland
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16
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Exploring the Conformational Changes Induced by Nanosecond Pulsed Electric Fields on the Voltage Sensing Domain of a Ca 2+ Channel. MEMBRANES 2021; 11:membranes11070473. [PMID: 34206827 PMCID: PMC8303878 DOI: 10.3390/membranes11070473] [Citation(s) in RCA: 9] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 03/15/2021] [Revised: 06/11/2021] [Accepted: 06/13/2021] [Indexed: 12/21/2022]
Abstract
Nanosecond Pulsed Electric Field (nsPEF or Nano Pulsed Stimulation, NPS) is a technology that delivers a series of pulses of high-voltage electric fields during a short period of time, in the order of nanoseconds. The main consequence of nsPEF upon cells is the formation of nanopores, which is followed by the gating of ionic channels. Literature is conclusive in that the physiological mechanisms governing ion channel gating occur in the order of milliseconds. Hence, understanding how these channels can be activated by a nsPEF would be an important step in order to conciliate fundamental biophysical knowledge with improved nsPEF applications. To get insights on both the kinetics and thermodynamics of ion channel gating induced by nsPEF, in this work, we simulated the Voltage Sensing Domain (VSD) of a voltage-gated Ca2+ channel, inserted in phospholipidic membranes with different concentrations of cholesterol. We studied the conformational changes of the VSD under a nsPEF mimicked by the application of a continuous electric field lasting 50 ns with different intensities as an approach to reveal novel mechanisms leading to ion channel gating in such short timescales. Our results show that using a membrane with high cholesterol content, under an nsPEF of 50 ns and E→ = 0.2 V/nm, the VSD undergoes major conformational changes. As a whole, our work supports the notion that membrane composition may act as an allosteric regulator, specifically cholesterol content, which is fundamental for the response of the VSD to an external electric field. Moreover, changes on the VSD structure suggest that the gating of voltage-gated Ca2+ channels by a nsPEF may be due to major conformational changes elicited in response to the external electric field. Finally, the VSD/cholesterol-bilayer under an nsPEF of 50 ns and E→ = 0.2 V/nm elicits a pore formation across the VSD suggesting a new non-reported effect of nsPEF into cells, which can be called a “protein mediated electroporation”.
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Carr L, Golzio M, Orlacchio R, Alberola G, Kolosnjaj-Tabi J, Leveque P, Arnaud-Cormos D, Rols MP. A nanosecond pulsed electric field (nsPEF) can affect membrane permeabilization and cellular viability in a 3D spheroids tumor model. Bioelectrochemistry 2021; 141:107839. [PMID: 34020398 DOI: 10.1016/j.bioelechem.2021.107839] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Key Words] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/20/2020] [Revised: 05/03/2021] [Accepted: 05/05/2021] [Indexed: 12/01/2022]
Abstract
Three-dimensional (3D) cellular models represent more realistically the complexity of in vivo tumors compared to 2D cultures. While 3D models were largely used in classical electroporation, the effects of nanosecond pulsed electric field (nsPEF) have been poorly investigated. In this study, we evaluated the biological effects induced by nsPEF on spheroid tumor model derived from the HCT-116 human colorectal carcinoma cell line. By varying the number of pulses (from 1 to 500) and the polarity (unipolar and bipolar), the response of nsPEF exposure (10 ns duration, 50 kV/cm) was assessed either immediately after the application of the pulses or over a period lasting up to 6 days. Membrane permeabilization and cellular death occurred following the application of at least 100 pulses. The extent of the response increased with the number of pulses, with a significant decrease of viability, 24 h post-exposure, when 250 and 500 pulses were applied. The effects were highly reduced when an equivalent number of bipolar pulses were delivered. This reduction was eliminated when a 100 ns interphase interval was introduced into the bipolar pulses. Altogether, our results show that nsPEF effects, previously observed at the single cell level, also occur in more realistic 3D tumor spheroids models.
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Affiliation(s)
- Lynn Carr
- Univ. Limoges, CNRS, XLIM, UMR 7252, F-87000 Limoges, France; School of Electronic Engineering, Bangor University, Bangor, UK
| | - Muriel Golzio
- Institut de Pharmacologie et de Biologie Structurale, Université de Toulouse, CNRS, UPS, 31077 Toulouse, France
| | - Rosa Orlacchio
- Univ. Limoges, CNRS, XLIM, UMR 7252, F-87000 Limoges, France
| | - Geraldine Alberola
- Institut de Pharmacologie et de Biologie Structurale, Université de Toulouse, CNRS, UPS, 31077 Toulouse, France
| | - Jelena Kolosnjaj-Tabi
- Institut de Pharmacologie et de Biologie Structurale, Université de Toulouse, CNRS, UPS, 31077 Toulouse, France
| | | | - Delia Arnaud-Cormos
- Univ. Limoges, CNRS, XLIM, UMR 7252, F-87000 Limoges, France; Institut Universitaire de France (IUF), 75005 Paris, France.
| | - Marie-Pierre Rols
- Institut de Pharmacologie et de Biologie Structurale, Université de Toulouse, CNRS, UPS, 31077 Toulouse, France.
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18
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5 ns electric pulses induce Ca 2+-dependent exocytotic release of catecholamine from adrenal chromaffin cells. Bioelectrochemistry 2021; 140:107830. [PMID: 33965669 DOI: 10.1016/j.bioelechem.2021.107830] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/28/2020] [Revised: 04/21/2021] [Accepted: 04/23/2021] [Indexed: 12/12/2022]
Abstract
Previously we reported that adrenal chromaffin cells exposed to a 5 ns, 5 MV/m pulse release the catecholamines norepinephrine (NE) and epinephrine (EPI) in a Ca2+-dependent manner. Here we determined that NE and EPI release increased with pulse number (one versus five and ten pulses at 1 Hz), established that release occurs by exocytosis, and characterized the exocytotic response in real-time. Evidence of an exocytotic mechanism was the appearance of dopamine-β-hydroxylase on the plasma membrane, and the demonstration by total internal reflection fluorescence microscopy studies that a train of five or ten pulses at 1 Hz triggered the release of the fluorescent dye acridine orange from secretory granules. Release events were Ca2+-dependent, longer-lived relative to those evoked by nicotinic receptor stimulation, and occurred with a delay of several seconds despite an immediate rise in Ca2+. In complementary studies, cells labeled with the plasma membrane fluorescent dye FM 1-43 and exposed to a train of ten pulses at 1 Hz underwent Ca2+-dependent increases in FM 1-43 fluorescence indicative of granule fusion with the plasma membrane due to exocytosis. These results demonstrate the effectiveness of ultrashort electric pulses for stimulating catecholamine release, signifying their promise as a novel electrostimulation modality for neurosecretion.
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Abstract
All living cells interact dynamically with a constantly changing world. Eukaryotes, in particular, evolved radically new ways to sense and react to their environment. These advances enabled new and more complex forms of cellular behaviour in eukaryotes, including directional movement, active feeding, mating, and responses to predation. But what are the key events and innovations during eukaryogenesis that made all of this possible? Here we describe the ancestral repertoire of eukaryotic excitability and discuss five major cellular innovations that enabled its evolutionary origin. The innovations include a vastly expanded repertoire of ion channels, the emergence of cilia and pseudopodia, endomembranes as intracellular capacitors, a flexible plasma membrane and the relocation of chemiosmotic ATP synthesis to mitochondria, which liberated the plasma membrane for more complex electrical signalling involved in sensing and reacting. We conjecture that together with an increase in cell size, these new forms of excitability greatly amplified the degrees of freedom associated with cellular responses, allowing eukaryotes to vastly outperform prokaryotes in terms of both speed and accuracy. This comprehensive new perspective on the evolution of excitability enriches our view of eukaryogenesis and emphasizes behaviour and sensing as major contributors to the success of eukaryotes. This article is part of the theme issue 'Basal cognition: conceptual tools and the view from the single cell'.
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Affiliation(s)
- Kirsty Y. Wan
- Living Systems Institute, University of Exeter, Stocker Road, Exeter EX4 4QD, UK
| | - Gáspár Jékely
- Living Systems Institute, University of Exeter, Stocker Road, Exeter EX4 4QD, UK
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20
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Abstract
The paper describes major issues related to the design of a portable SiC-based DC supply developed for evaluation of a high-voltage Marx generator. This generator is developed to be a part of an electromagnetic cannon providing very high voltage and current pulses aiming at the destruction of electronics equipment in a specific area. The portable DC supply offers a very high voltage gain: input voltage is 24 V, while the generator requires supply voltages up to 50 kV. Thus, the system contains two stages designed on the basis of SiC power devices operating with frequencies up to 100 kHz. At first, the input voltage is boosted up to 400 V by a non-isolated double-boost converter, and then a resonant DC-DC converter with a special transformer elevates the voltage to the required level. In the paper, the main components of the laboratory setup are presented, and experimental results of the DC supply and whole system are also shown.
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21
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Rajabi F, Gusbeth C, Frey W, Maisch J, Nick P. Nanosecond pulsed electrical fields enhance product recovery in plant cell fermentation. PROTOPLASMA 2020; 257:1585-1594. [PMID: 32651872 PMCID: PMC7567687 DOI: 10.1007/s00709-020-01534-9] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 04/06/2020] [Accepted: 07/03/2020] [Indexed: 05/20/2023]
Abstract
The potential of pharmacologically active secondary plant metabolites is limited by the low yield from often rare plants, and the lack of economically feasible chemical synthesis of these complex compounds. Plant cell fermentation offers an alternative strategy to overcome these constraints. However, the efficiency of this approach is limited by intracellular sequestration of the products, such that continuous bioprocessing is not possible. As a precondition for such a, more attractive, continuous process, it is of great importance to stimulate the export of the product into the medium without impairing viability and, thus, the productivity of the cells. Using nicotine alkaloids of tobacco as a case study, an alternative strategy is explored, where nanosecond pulsed electric fields (nsPEFs) are applied for the efficient downstream recovery of the products. To maintain cell viability and allow for the further use of biomass, cells were exposed to strong (1-20 kV·cm-1), but very short (10-100 ns) electric pulses, which leads to a temporary permeabilisation of cell membranes. Using two transgenic cell lines, where two key genes involved in the metabolism of the anti-Alzheimer compound nornicotine were overexpressed, we could show that this nsPEF treatment improved the partitioning of some nicotine alkaloids to the culture medium without impairing viability, nor the synthesis of alkaloids. However, this release was only partial and did not work for nornicotine. Thus, nsPEFs produced a fractionation of alkaloids. We explain this electrofractionation by a working model considering the differential intracellular compartmentalization of nicotineic alkaloids.
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Affiliation(s)
- Fatemeh Rajabi
- Molecular Cell Biology, Botanical Institute, Karlsruhe Institute of Technology, Karlsruhe, Germany
| | - Christian Gusbeth
- Institute for Pulsed Power and Microwave Technology (IHM), Karlsruhe Institute of Technology, Karlsruhe, Germany
| | - Wolfgang Frey
- Institute for Pulsed Power and Microwave Technology (IHM), Karlsruhe Institute of Technology, Karlsruhe, Germany
| | - Jan Maisch
- Molecular Cell Biology, Botanical Institute, Karlsruhe Institute of Technology, Karlsruhe, Germany
| | - Peter Nick
- Molecular Cell Biology, Botanical Institute, Karlsruhe Institute of Technology, Karlsruhe, Germany.
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22
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Novickij V, Malyško V, Želvys A, Balevičiūtė A, Zinkevičienė A, Novickij J, Girkontaitė I. Electrochemotherapy Using Doxorubicin and Nanosecond Electric Field Pulses: A Pilot in Vivo Study. Molecules 2020; 25:E4601. [PMID: 33050300 PMCID: PMC7587179 DOI: 10.3390/molecules25204601] [Citation(s) in RCA: 8] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/22/2020] [Revised: 10/06/2020] [Accepted: 10/09/2020] [Indexed: 12/23/2022] Open
Abstract
Pulsed electric field (PEF) is frequently used for intertumoral drug delivery resulting in a well-known anticancer treatment-electrochemotherapy. However, electrochemotherapy is associated with microsecond range of electrical pulses, while nanosecond range electrochemotherapy is almost non-existent. In this work, we analyzed the feasibility of nanosecond range pulse bursts for successful doxorubicin-based electrochemotherapy in vivo. The conventional microsecond (1.4 kV/cm × 100 µs × 8) procedure was compared to the nanosecond (3.5 kV/cm × 800 ns × 250) non-thermal PEF-based treatment. As a model, Sp2/0 tumors were developed. Additionally, basic current and voltage measurements were performed to detect the characteristic conductivity-dependent patterns and to serve as an indicator of successful tumor permeabilization both in the nano and microsecond pulse range. It was shown that nano-electrochemotherapy can be the logical evolution of the currently established European Standard Operating Procedures for Electrochemotherapy (ESOPE) protocols, offering better energy control and equivalent treatment efficacy.
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Affiliation(s)
- Vitalij Novickij
- Faculty of Electronics, Vilnius Gediminas Technical University, 03227 Vilnius, Lithuania; (V.M.); (J.N.)
| | - Veronika Malyško
- Faculty of Electronics, Vilnius Gediminas Technical University, 03227 Vilnius, Lithuania; (V.M.); (J.N.)
| | - Augustinas Želvys
- Department of Immunology, State Research Institute Centre for Innovative Medicine, 08406 Vilnius, Lithuania; (A.Ž.); (A.B.); (A.Z.); (I.G.)
| | - Austėja Balevičiūtė
- Department of Immunology, State Research Institute Centre for Innovative Medicine, 08406 Vilnius, Lithuania; (A.Ž.); (A.B.); (A.Z.); (I.G.)
| | - Auksė Zinkevičienė
- Department of Immunology, State Research Institute Centre for Innovative Medicine, 08406 Vilnius, Lithuania; (A.Ž.); (A.B.); (A.Z.); (I.G.)
| | - Jurij Novickij
- Faculty of Electronics, Vilnius Gediminas Technical University, 03227 Vilnius, Lithuania; (V.M.); (J.N.)
| | - Irutė Girkontaitė
- Department of Immunology, State Research Institute Centre for Innovative Medicine, 08406 Vilnius, Lithuania; (A.Ž.); (A.B.); (A.Z.); (I.G.)
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23
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Zoccoler M, de Oliveira PX. METROID: an automated method for robust quantification of subcellular fluorescence events at low SNR. BMC Bioinformatics 2020; 21:332. [PMID: 32709217 PMCID: PMC7379836 DOI: 10.1186/s12859-020-03661-9] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/02/2019] [Accepted: 07/14/2020] [Indexed: 11/23/2022] Open
Abstract
Background In cell biology, increasing focus has been directed to fast events at subcellular space with the advent of fluorescent probes. As an example, voltage sensitive dyes (VSD) have been used to measure membrane potentials. Yet, even the most recently developed genetically encoded voltage sensors have demanded exhausting signal averaging through repeated experiments to quantify action potentials (AP). This analysis may be further hampered in subcellular signals defined by small regions of interest (ROI), where signal-to-noise ratio (SNR) may fall substantially. Signal processing techniques like blind source separation (BSS) are designed to separate a multichannel mixture of signals into uncorrelated or independent sources, whose potential to separate ROI signal from noise has been poorly explored. Our aims are to develop a method capable of retrieving subcellular events with minimal a priori information from noisy cell fluorescence images and to provide it as a computational tool to be readily employed by the scientific community. Results In this paper, we have developed METROID (Morphological Extraction of Transmembrane potential from Regions Of Interest Device), a new computational tool to filter fluorescence signals from multiple ROIs, whose code and graphical interface are freely available. In this tool, we developed a new ROI definition procedure to automatically generate similar-area ROIs that follow cell shape. In addition, simulations and real data analysis were performed to recover AP and electroporation signals contaminated by noise by means of four types of BSS: Principal Component Analysis (PCA), Independent Component Analysis (ICA), and two versions with discrete wavelet transform (DWT). All these strategies allowed for signal extraction at low SNR (− 10 dB) without apparent signal distortion. Conclusions We demonstrate the great capability of our method to filter subcellular signals from noisy fluorescence images in a single trial, avoiding repeated experiments. We provide this novel biomedical application with a graphical user interface at 10.6084/m9.figshare.11344046.v1, and its code and datasets are available in GitHub at https://github.com/zoccoler/metroid.
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Affiliation(s)
- Marcelo Zoccoler
- Department of Biomedical Engineering (DEB), School of Electrical and Computer Engineering, University of Campinas, 400, Albert Einstein Avenue, Campinas, SP, 13083-852, Brazil.
| | - Pedro X de Oliveira
- Department of Biomedical Engineering (DEB), School of Electrical and Computer Engineering, University of Campinas, 400, Albert Einstein Avenue, Campinas, SP, 13083-852, Brazil.,Center for Biomedical Engineering (CEB), University of Campinas, Campinas, SP, Brazil
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Pakhomov AG, Pakhomova ON. The interplay of excitation and electroporation in nanosecond pulse stimulation. Bioelectrochemistry 2020; 136:107598. [PMID: 32711366 DOI: 10.1016/j.bioelechem.2020.107598] [Citation(s) in RCA: 22] [Impact Index Per Article: 5.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/06/2020] [Revised: 07/09/2020] [Accepted: 07/10/2020] [Indexed: 12/11/2022]
Abstract
Conventional electric stimuli of micro- and millisecond duration excite or activate cells at voltages 10-100 times below the electroporation threshold. This ratio is remarkably different for nanosecond electric pulses (nsEP), which caused excitation and activation only at or above the electroporation threshold in diverse cell lines, primary cardiomyocytes, neurons, and chromaffin cells. Depolarization to the excitation threshold often results from (or is assisted by) the loss of the resting membrane potential due to ion leaks across the membrane permeabilized by nsEP. Slow membrane resealing and the build-up of electroporation damages prevent repetitive excitation by nsEP. However, peripheral nerves and muscles are exempt from this rule and withstand multiple cycles of excitation by nsEP without the loss of function or signs of electroporation. We show that the damage-free excitation by nsEP may be enabled by the membrane charging time constant sufficiently large to (1) cap the peak transmembrane voltage during nsEP below the electroporation threshold, and (2) extend the post-nsEP depolarization long enough to activate voltage-gated ion channels. The low excitatory efficacy of nsEP compared to longer pulses makes them advantageous for medical applications where the neuromuscular excitation is an unwanted side effect, such as electroporation-based cancer and tissue ablation.
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Affiliation(s)
- Andrei G Pakhomov
- Frank Reidy Research Center for Bioelectrics, Old Dominion University, Norfolk, VA 23508, USA.
| | - Olga N Pakhomova
- Frank Reidy Research Center for Bioelectrics, Old Dominion University, Norfolk, VA 23508, USA
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25
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Rems L, Kasimova MA, Testa I, Delemotte L. Pulsed Electric Fields Can Create Pores in the Voltage Sensors of Voltage-Gated Ion Channels. Biophys J 2020; 119:190-205. [PMID: 32559411 PMCID: PMC7335976 DOI: 10.1016/j.bpj.2020.05.030] [Citation(s) in RCA: 29] [Impact Index Per Article: 7.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/11/2019] [Revised: 03/31/2020] [Accepted: 05/15/2020] [Indexed: 12/21/2022] Open
Abstract
Pulsed electric fields are increasingly used in medicine to transiently increase the cell membrane permeability via electroporation to deliver therapeutic molecules into the cell. One type of event that contributes to this increase in membrane permeability is the formation of pores in the membrane lipid bilayer. However, electrophysiological measurements suggest that membrane proteins are affected as well, particularly voltage-gated ion channels (VGICs). The molecular mechanisms by which the electric field could affects these molecules remain unidentified. In this study, we used molecular dynamics simulations to unravel the molecular events that take place in different VGICs when exposing them to electric fields mimicking electroporation conditions. We show that electric fields can induce pores in the voltage-sensor domains (VSDs) of different VGICs and that these pores form more easily in some channels than in others. We demonstrate that poration is more likely in VSDs that are more hydrated and are electrostatically more favorable for the entry of ions. We further show that pores in VSDs can expand into so-called complex pores, which become stabilized by lipid headgroups. Our results suggest that such complex pores are considerably more stable than conventional lipid pores, and their formation can lead to severe unfolding of VSDs from the channel. We anticipate that such VSDs become dysfunctional and unable to respond to changes in transmembrane voltage, which is in agreement with previous electrophysiological measurements showing a decrease in the voltage-dependent transmembrane ionic currents after pulse treatment. Finally, we discuss the possibility of activation of VGICs by submicrosecond-duration pulses. Overall, our study reveals a new, to our knowledge, mechanism of electroporation through membranes containing VGICs.
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Affiliation(s)
- Lea Rems
- Science for Life Laboratory, Department of Applied Physics, KTH Royal Institute of Technology, Solna, Sweden
| | - Marina A Kasimova
- Science for Life Laboratory, Department of Applied Physics, KTH Royal Institute of Technology, Solna, Sweden
| | - Ilaria Testa
- Science for Life Laboratory, Department of Applied Physics, KTH Royal Institute of Technology, Solna, Sweden
| | - Lucie Delemotte
- Science for Life Laboratory, Department of Applied Physics, KTH Royal Institute of Technology, Solna, Sweden.
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26
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Nath S, Sinha KP, Thaokar RM. Development of transmembrane potential in concentric spherical, confocal spheroidal, and bispherical vesicles subjected to nanosecond-pulse electric field. Phys Rev E 2020; 101:062407. [PMID: 32688463 DOI: 10.1103/physreve.101.062407] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/23/2020] [Accepted: 05/11/2020] [Indexed: 06/11/2023]
Abstract
Electroporation of concentric compound spherical and confocal spheroidal as well as eccentric compound spherical vesicles, considered to be good models for corresponding nucleate cells, are investigated with an emphasis on their response to nanosecond pulse electric field (nsPEF). Analytical models are developed for the estimation of the transmembrane potential (TMP) across the bilayers of the inner and the outer vesicles and finite-element simulations are also carried out for the eccentric case. Our calculations show that with an increase in the aspect ratio, while the TMP decreases when nsPEF is used, it increases for confocal spheroids when the pulse width is greater than the membrane charging time, leading to fully charged vesicles. Bipolar pulses are shown to effectively control the TMP for a desired time period in the nsPEF regime, and a fast decay of the TMP to zero can be achieved by judicious use of pulse polarity. The external conductivity is found to significantly influence the TMP in nsPEF, unlike millisecond pulses where its effect is insignificant. Additionally the critical electric field required to induce a TMP of 1 V at the inner vesicle is presented for different pulse widths, rise time, as well as membrane capacitance, and the TMP of the outer vesicle is found to be within limits of reversible poration. It is found that the maximum TMP has a roughly linear dependence on the outer aspect ratio of the vesicle. We also introduce a new method to obtain the particular solution to the Laplace equation for bispherical system, and it is validated with finite-element simulations. Our study on nsPEF electroporation of bispherical vesicles shows that the north pole TMP is typically greater than the south pole, thereby suggesting the typical pathway a charged species might take inside an eccentric nucleate cell under electroporation.
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Affiliation(s)
- Shoubhanik Nath
- Department of Chemical Engineering, IIT Bombay, Mumbai 400076, India
| | | | - Rochish M Thaokar
- Department of Chemical Engineering, IIT Bombay, Mumbai 400076, India
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Papachristou I, Silve A, Jianu A, Wüstner R, Nazarova N, Müller G, Frey W. Evaluation of pulsed electric fields effect on the microalgae cell mechanical stability through high pressure homogenization. ALGAL RES 2020. [DOI: 10.1016/j.algal.2020.101847] [Citation(s) in RCA: 9] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
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Kašėta V, Kaušylė A, Kavaliauskaitė J, Petreikytė M, Stirkė A, Biziulevičienė G. Detection of intracellular biomarkers in viable cells using millisecond pulsed electric fields. Exp Cell Res 2020; 389:111877. [DOI: 10.1016/j.yexcr.2020.111877] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/15/2019] [Revised: 01/06/2020] [Accepted: 01/24/2020] [Indexed: 01/22/2023]
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Effects of Actin Cytoskeleton Disruption on Electroporation In Vitro. Appl Biochem Biotechnol 2020; 191:1545-1561. [PMID: 32157625 DOI: 10.1007/s12010-020-03271-4] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/23/2019] [Accepted: 02/13/2020] [Indexed: 01/26/2023]
Abstract
The role of actin fibers in cellular responses to external electric pulses is not clear yet. In this study, we utilized the blocker of actin polymerization, cytochalasin D (cytoD), and investigated its effects on the electropore generation. Eight 100 μs electric pulses of sub-kilovolt per centimeter voltage with 100 ms intervals were applied to adhered cells in vitro, and the membrane permeability was quantified using membrane-impermeable propidium iodide (PI) dye. With cytoD application, the transfer of PI dye decreased significantly in all the applied voltages. At the same time, the roughness of cells increased, the membrane stiffness decreased, and the transmembrane resting potential decreased. Our result supports that actin fibers have clear effects on electroporation through modulating membrane properties including transmembrane resting potential.
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Roome CJ, Kuhn B. Voltage imaging with ANNINE dyes and two-photon microscopy of Purkinje dendrites in awake mice. Neurosci Res 2020; 152:15-24. [DOI: 10.1016/j.neures.2019.11.007] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/18/2019] [Revised: 11/07/2019] [Accepted: 11/12/2019] [Indexed: 12/13/2022]
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Kim HB, Lee S, Shen Y, Ryu PD, Lee Y, Chung JH, Sung CK, Baik KY. Physicochemical factors that affect electroporation of lung cancer and normal cell lines. Biochem Biophys Res Commun 2019; 517:703-708. [PMID: 31387747 DOI: 10.1016/j.bbrc.2019.07.119] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/24/2019] [Accepted: 07/30/2019] [Indexed: 01/04/2023]
Abstract
Electroporation is used for cancer therapy to efficiently destroy cancer tissues by transferring anticancer drugs into cancer cells or by irreversible tumor ablation without resealing pores. There is growing interest in the electroporation method for the treatment of lung cancer, which has the highest mortality rate among cancers. Improving the cancer cell selectivity has the potential to expand its use. However, the factors that influence the cell selectivity of electroporation are debatable. We aimed to identify the important factors that influence the efficiency of electroporation in lung cells. The electropermeabilization of lung cancer cells (H460, A549, and HCC1588) and normal lung cells (MRC5, WI26 and L132) was evaluated by the transfer of fluorescence dyes. We found that membrane permeabilization increased as cell size, membrane stiffness, resting transmembrane potential, and lipid cholesterol ratio increased. Among them, lipid composition was found to be the most relevant factor in the electroporation of lung cells. Our results provide insight into the differences between lung cancer cells and normal lung cells and provide a basis for enhancing the sensitivity of lung cancers cells to electroporation.
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Affiliation(s)
- Hong Bae Kim
- Department of Biosystems & Biomaterials Science and Engineering, Seoul National University, Seoul, 08826, South Korea
| | - Seho Lee
- Department of Brain and Cognitive Engineering, Korea University, Seoul, 02841, South Korea
| | - Yiming Shen
- Department of Veterinary Pharmacology, College of Veterinary Medicine and Research Institute for Veterinary Science, Seoul National University, Seoul, 08826, South Korea
| | - Pan-Dong Ryu
- Department of Veterinary Pharmacology, College of Veterinary Medicine and Research Institute for Veterinary Science, Seoul National University, Seoul, 08826, South Korea
| | - Yunmi Lee
- Department of Chemistry, Kwangwoon University, Seoul, 01897, South Korea
| | - Jong Hoon Chung
- Department of Biosystems & Biomaterials Science and Engineering, Seoul National University, Seoul, 08826, South Korea
| | - Chang Kyu Sung
- Department of Radiology, Seoul National University College of Medicine, Seoul, 07061, South Korea.
| | - Ku Youn Baik
- Department of Electrical and Biological Physics, Kwangwoon University, Seoul, 01897, South Korea.
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Kuhn B, Roome CJ. Primer to Voltage Imaging With ANNINE Dyes and Two-Photon Microscopy. Front Cell Neurosci 2019; 13:321. [PMID: 31379507 PMCID: PMC6646528 DOI: 10.3389/fncel.2019.00321] [Citation(s) in RCA: 22] [Impact Index Per Article: 4.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/23/2019] [Accepted: 07/01/2019] [Indexed: 11/24/2022] Open
Abstract
ANNINE-6 and ANNINE-6plus are voltage-sensitive dyes that when combined with two-photon microscopy are ideal for recording of neuronal voltages in vivo, in both bulk loaded tissue and the dendrites of single neurons. Here, we describe in detail but for a broad audience the voltage sensing mechanism of fast voltage-sensitive dyes, with a focus on ANNINE dyes, and how voltage imaging can be optimized with one-photon and two-photon excitation. Under optimized imaging conditions the key strengths of ANNINE dyes are their high sensitivity (0.5%/mV), neglectable bleaching and phototoxicity, a linear response to membrane potential, and a temporal resolution which is faster than the optical imaging devices currently used in neurobiology (order of nanoseconds). ANNINE dyes in combination with two-photon microscopy allow depth-resolved voltage imaging in bulk loaded tissue to study average membrane voltage oscillations and sensory responses. Alternatively, if ANNINE-6plus is applied internally, supra and sub threshold voltage changes can be recorded from dendrites of single neurons in awake animals. Interestingly, in our experience ANNINE-6plus labeling is impressively stable in vivo, such that voltage imaging from single Purkinje neuron dendrites can be performed for 2 weeks after a single electroporation of the neuron. Finally, to maximize their potential for neuroscience studies, voltage imaging with ANNINE dyes and two-photon microscopy can be combined with electrophysiological recording, calcium imaging, and/or pharmacology, even in awake animals.
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Affiliation(s)
- Bernd Kuhn
- Okinawa Institute of Science and Technology Graduate University, Okinawa, Japan
| | - Christopher J Roome
- Okinawa Institute of Science and Technology Graduate University, Okinawa, Japan
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Vadlamani RA, Nie Y, Detwiler DA, Dhanabal A, Kraft AM, Kuang S, Gavin TP, Garner AL. Nanosecond pulsed electric field induced proliferation and differentiation of osteoblasts and myoblasts. J R Soc Interface 2019; 16:20190079. [PMID: 31213169 DOI: 10.1098/rsif.2019.0079] [Citation(s) in RCA: 16] [Impact Index Per Article: 3.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/16/2022] Open
Abstract
Low-intensity electric fields can induce changes in cell differentiation and cytoskeletal stresses that facilitate manipulation of osteoblasts and mesenchymal stem cells; however, the application times (tens of minutes) are of the order of physiological mechanisms, which can complicate treatment consistency. Intense nanosecond pulsed electric fields (nsPEFs) can overcome these challenges by inducing similar stresses on shorter timescales while additionally inducing plasma membrane nanoporation, ion transport and intracellular structure manipulation. This paper shows that treating myoblasts and osteoblasts with five 300 ns PEFs with intensities from 1.5 to 25 kV cm-1 increased proliferation and differentiation. While nsPEFs above 5 kV cm-1 decreased myoblast population growth, 10 and 20 kV cm-1 trains increased myoblast population by approximately fivefold 48 h after exposure when all cell densities were set to the same level after exposure. Three trials of the PEF-treated osteoblasts showed that PEF trains between 2.5 and 10 kV cm-1 induced the greatest population growth compared to the control 48 h after treatment. Trains of nsPEFs between 1.5 and 5 kV cm-1 induced the most nodule formation in osteoblasts, indicating bone formation. These results demonstrate the potential utility for nsPEFs to rapidly modulate stem cells for proliferation and differentiation and motivate future experiments to optimize PEF parameters for in vivo applications.
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Affiliation(s)
- Ram Anand Vadlamani
- 1 School of Nuclear Engineering, Purdue University , West Lafayette, IN 47907 , USA
| | - Yaohui Nie
- 2 Department of Health and Kinesiology, Purdue University , West Lafayette, IN 47907 , USA
| | | | - Agni Dhanabal
- 3 Department of Agricultural and Biological Engineering, Purdue University , West Lafayette, IN 47907 , USA
| | - Alan M Kraft
- 1 School of Nuclear Engineering, Purdue University , West Lafayette, IN 47907 , USA
| | - Shihuan Kuang
- 4 Department of Animal Sciences, Purdue University , West Lafayette, IN 47907 , USA
| | - Timothy P Gavin
- 2 Department of Health and Kinesiology, Purdue University , West Lafayette, IN 47907 , USA
| | - Allen L Garner
- 1 School of Nuclear Engineering, Purdue University , West Lafayette, IN 47907 , USA.,3 Department of Agricultural and Biological Engineering, Purdue University , West Lafayette, IN 47907 , USA.,5 School of Electrical and Computer Engineering, Purdue University , West Lafayette, IN 47907 , USA
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Kotnik T, Rems L, Tarek M, Miklavčič D. Membrane Electroporation and Electropermeabilization: Mechanisms and Models. Annu Rev Biophys 2019; 48:63-91. [PMID: 30786231 DOI: 10.1146/annurev-biophys-052118-115451] [Citation(s) in RCA: 339] [Impact Index Per Article: 67.8] [Reference Citation Analysis] [Abstract] [Key Words] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/09/2022]
Abstract
Exposure of biological cells to high-voltage, short-duration electric pulses causes a transient increase in their plasma membrane permeability, allowing transmembrane transport of otherwise impermeant molecules. In recent years, large steps were made in the understanding of underlying events. Formation of aqueous pores in the lipid bilayer is now a widely recognized mechanism, but evidence is growing that changes to individual membrane lipids and proteins also contribute, substantiating the need for terminological distinction between electroporation and electropermeabilization. We first revisit experimental evidence for electrically induced membrane permeability, its correlation with transmembrane voltage, and continuum models of electropermeabilization that disregard the molecular-level structure and events. We then present insights from molecular-level modeling, particularly atomistic simulations that enhance understanding of pore formation, and evidence of chemical modifications of membrane lipids and functional modulation of membrane proteins affecting membrane permeability. Finally, we discuss the remaining challenges to our full understanding of electroporation and electropermeabilization.
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Affiliation(s)
- Tadej Kotnik
- Faculty of Electrical Engineering, University of Ljubljana, SI-1000 Ljubljana, Slovenia; ,
| | - Lea Rems
- Science for Life Laboratory, Department of Applied Physics, KTH Royal Institute of Technology, 17165 Solna, Sweden;
| | - Mounir Tarek
- Université de Lorraine, CNRS, LPCT, F-54000 Nancy, France;
| | - Damijan Miklavčič
- Faculty of Electrical Engineering, University of Ljubljana, SI-1000 Ljubljana, Slovenia; ,
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Du X, Wang J, Zhou Q, Zhang L, Wang S, Zhang Z, Yao C. Advanced physical techniques for gene delivery based on membrane perforation. Drug Deliv 2018; 25:1516-1525. [PMID: 29968512 PMCID: PMC6058615 DOI: 10.1080/10717544.2018.1480674] [Citation(s) in RCA: 71] [Impact Index Per Article: 11.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/18/2022] Open
Abstract
Gene delivery as a promising and valid tool has been used for treating many serious diseases that conventional drug therapies cannot cure. Due to the advancement of physical technology and nanotechnology, advanced physical gene delivery methods such as electroporation, magnetoporation, sonoporation and optoporation have been extensively developed and are receiving increasing attention, which have the advantages of briefness and nontoxicity. This review introduces the technique detail of membrane perforation, with a brief discussion for future development, with special emphasis on nanoparticles mediated optoporation that have developed as an new alternative transfection technique in the last two decades. In particular, the advanced physical approaches development and new technology are highlighted, which intends to stimulate rapid advancement of perforation techniques, develop new delivery strategies and accelerate application of these techniques in clinic.
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Affiliation(s)
- Xiaofan Du
- a Key Laboratory of Biomedical Information Engineering of Ministry of Education, Institute of Biomedical Analytical Technology and Instrumentation , School of Life Science and Technology, Xi'an Jiaotong University , Xi'an , People's Republic of China
| | - Jing Wang
- a Key Laboratory of Biomedical Information Engineering of Ministry of Education, Institute of Biomedical Analytical Technology and Instrumentation , School of Life Science and Technology, Xi'an Jiaotong University , Xi'an , People's Republic of China
| | - Quan Zhou
- a Key Laboratory of Biomedical Information Engineering of Ministry of Education, Institute of Biomedical Analytical Technology and Instrumentation , School of Life Science and Technology, Xi'an Jiaotong University , Xi'an , People's Republic of China
| | - Luwei Zhang
- a Key Laboratory of Biomedical Information Engineering of Ministry of Education, Institute of Biomedical Analytical Technology and Instrumentation , School of Life Science and Technology, Xi'an Jiaotong University , Xi'an , People's Republic of China
| | - Sijia Wang
- a Key Laboratory of Biomedical Information Engineering of Ministry of Education, Institute of Biomedical Analytical Technology and Instrumentation , School of Life Science and Technology, Xi'an Jiaotong University , Xi'an , People's Republic of China
| | - Zhenxi Zhang
- a Key Laboratory of Biomedical Information Engineering of Ministry of Education, Institute of Biomedical Analytical Technology and Instrumentation , School of Life Science and Technology, Xi'an Jiaotong University , Xi'an , People's Republic of China
| | - Cuiping Yao
- a Key Laboratory of Biomedical Information Engineering of Ministry of Education, Institute of Biomedical Analytical Technology and Instrumentation , School of Life Science and Technology, Xi'an Jiaotong University , Xi'an , People's Republic of China
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36
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Ricard C, Arroyo ED, He CX, Portera-Cailliau C, Lepousez G, Canepari M, Fiole D. Two-photon probes for in vivo multicolor microscopy of the structure and signals of brain cells. Brain Struct Funct 2018; 223:3011-3043. [PMID: 29748872 PMCID: PMC6119111 DOI: 10.1007/s00429-018-1678-1] [Citation(s) in RCA: 27] [Impact Index Per Article: 4.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/12/2017] [Accepted: 05/03/2018] [Indexed: 02/07/2023]
Abstract
Imaging the brain of living laboratory animals at a microscopic scale can be achieved by two-photon microscopy thanks to the high penetrability and low phototoxicity of the excitation wavelengths used. However, knowledge of the two-photon spectral properties of the myriad fluorescent probes is generally scarce and, for many, non-existent. In addition, the use of different measurement units in published reports further hinders the design of a comprehensive imaging experiment. In this review, we compile and homogenize the two-photon spectral properties of 280 fluorescent probes. We provide practical data, including the wavelengths for optimal two-photon excitation, the peak values of two-photon action cross section or molecular brightness, and the emission ranges. Beyond the spectroscopic description of these fluorophores, we discuss their binding to biological targets. This specificity allows in vivo imaging of cells, their processes, and even organelles and other subcellular structures in the brain. In addition to probes that monitor endogenous cell metabolism, studies of healthy and diseased brain benefit from the specific binding of certain probes to pathology-specific features, ranging from amyloid-β plaques to the autofluorescence of certain antibiotics. A special focus is placed on functional in vivo imaging using two-photon probes that sense specific ions or membrane potential, and that may be combined with optogenetic actuators. Being closely linked to their use, we examine the different routes of intravital delivery of these fluorescent probes according to the target. Finally, we discuss different approaches, strategies, and prerequisites for two-photon multicolor experiments in the brains of living laboratory animals.
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Affiliation(s)
- Clément Ricard
- Brain Physiology Laboratory, CNRS UMR 8118, 75006, Paris, France
- Faculté de Sciences Fondamentales et Biomédicales, Université Paris Descartes, PRES Sorbonne Paris Cité, 75006, Paris, France
- Fédération de Recherche en Neurosciences FR 3636, Paris, 75006, France
| | - Erica D Arroyo
- Department of Neurology, David Geffen School of Medicine, University of California, Los Angeles, USA
| | - Cynthia X He
- Department of Neurology, David Geffen School of Medicine, University of California, Los Angeles, USA
| | - Carlos Portera-Cailliau
- Department of Neurology, David Geffen School of Medicine, University of California, Los Angeles, USA
- Department of Neurobiology, David Geffen School of Medicine, University of California, Los Angeles, USA
| | - Gabriel Lepousez
- Unité Perception et Mémoire, Département de Neuroscience, Institut Pasteur, 25 rue du Docteur Roux, 75724, Paris Cedex 15, France
| | - Marco Canepari
- Laboratory for Interdisciplinary Physics, UMR 5588 CNRS and Université Grenoble Alpes, 38402, Saint Martin d'Hères, France
- Laboratories of Excellence, Ion Channel Science and Therapeutics, Grenoble, France
- Institut National de la Santé et Recherche Médicale (INSERM), Grenoble, France
| | - Daniel Fiole
- Unité Biothérapies anti-Infectieuses et Immunité, Département des Maladies Infectieuses, Institut de Recherche Biomédicale des Armées, BP 73, 91223, Brétigny-sur-Orge cedex, France.
- Human Histopathology and Animal Models, Infection and Epidemiology Department, Institut Pasteur, 28 rue du docteur Roux, 75725, Paris Cedex 15, France.
- ESRF-The European Synchrotron, 38043, Grenoble cedex, France.
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37
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Gowrishankar TR, Stern JV, Smith KC, Weaver JC. Nanopore occlusion: A biophysical mechanism for bipolar cancellation in cell membranes. Biochem Biophys Res Commun 2018; 503:1194-1199. [DOI: 10.1016/j.bbrc.2018.07.024] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/04/2018] [Accepted: 07/06/2018] [Indexed: 12/21/2022]
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38
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Ryan HA, Hirakawa S, Yang E, Zhou C, Xiao S. High-Voltage, Multiphasic, Nanosecond Pulses to Modulate Cellular Responses. IEEE TRANSACTIONS ON BIOMEDICAL CIRCUITS AND SYSTEMS 2018; 12:338-350. [PMID: 29570061 DOI: 10.1109/tbcas.2017.2786586] [Citation(s) in RCA: 20] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/08/2023]
Abstract
Nanosecond electric pulses are an effective power source in plasma medicine and biological stimulation, in which biophysical responses are governed by peak power and not energy. While uniphasic nanosecond pulse generators are widely available, the recent discovery that biological effects can be uniquely modulated by reversing the polarity of nanosecond duration pulses calls for the development of a multimodal pulse generator. This paper describes a method to generate nanosecond multiphasic pulses for biomedical use, and specifically demonstrates its ability to cancel or enhance cell swelling and blebbing. The generator consists of a series of the fundamental module, which includes a capacitor and a MOSFET switch. A positive or a negative phase pulse module can be produced based on how the switch is connected. Stacking the modules in series can increase the voltage up to 5 kV. Multiple stacks in parallel can create multiphase outputs. As each stack is independently controlled and charged, multiphasic pulses can be created to produce flexible and versatile pulse waveforms. The circuit topology can be used for high-frequency uniphasic or biphasic nanosecond burst pulse production, creating numerous opportunities for the generator in electroporation applications, tissue ablation, wound healing, and nonthermal plasma generation.
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39
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Schoenbach KH. From the basic science of biological effects of ultrashort electrical pulses to medical therapies. Bioelectromagnetics 2018. [DOI: 10.1002/bem.22117] [Citation(s) in RCA: 21] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/04/2023]
Affiliation(s)
- Karl H. Schoenbach
- Frank Reidy Research Center for Bioelectrics; Old Dominion University; Norfolk Virginia
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40
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Vijayarangan V, Delalande A, Dozias S, Pouvesle JM, Pichon C, Robert E. Cold Atmospheric Plasma Parameters Investigation for Efficient Drug Delivery in HeLa Cells. IEEE TRANSACTIONS ON RADIATION AND PLASMA MEDICAL SCIENCES 2018. [DOI: 10.1109/trpms.2017.2759322] [Citation(s) in RCA: 28] [Impact Index Per Article: 4.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/08/2022]
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41
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Ahmed S, Miyawaki O, Matsumura K. Enhanced Adsorption of a Protein-Nanocarrier Complex onto Cell Membranes through a High Freeze Concentration by a Polyampholyte Cryoprotectant. LANGMUIR : THE ACS JOURNAL OF SURFACES AND COLLOIDS 2018; 34:2352-2362. [PMID: 29361227 DOI: 10.1021/acs.langmuir.7b03622] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/07/2023]
Abstract
The transportation of biomolecules into cells is of great importance in tissue engineering and as stimulation for antitumor immune cells. Previous freezing strategies at ultracold temperatures (-80 °C) used for intracellular transportation exhibit certain limitations such as extended time requirements and harsh delivery system conditions. Thus, the need remains to develop simplified methods for safe nanomaterial delivery. Here, we demonstrated a unique strategy based on the ice-crystallization-induced freeze concentration for protein intracellular delivery in combination with a polyampholyte cryoprotectant. We found that upon sustained lowering of the temperature from -6 to -20 °C over a short duration, the adsorption of proteins onto the peripheral cell membrane was markedly increased through the facile ice-crystallization-induced freeze concentration. Furthermore, we proposed a freeze concentration factor (α) that depends on the freezing-point depression and is estimated from an analysis of the fraction of frozen water. Notably, the α values of the polyampholyte cryoprotectant were 8-fold higher than those of the currently used cryoprotectant dimethyl sulfoxide (DMSO) at particular temperatures of interest. Our results illustrate that the presence of a polyampholyte cryoprotectant significantly enhanced the adsorption of the protein/nanocarrier complex onto membranes compared to that obtained with DMSO because of the high freeze concentration. The present study demonstrated the direct relationship between freezing and the penetration of proteins across the periphery of the cell membrane by means of increased concentration during freezing. These results may be useful in providing a guideline for the intracellular delivery of biomacromolecules using ice-crystallization-induced continuous freezing combined with polyampholyte cryoprotectants.
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Affiliation(s)
- Sana Ahmed
- School of Materials Science, Japan Advanced Institute of Science and Technology , Nomi, Ishikawa 923-1292, Japan
| | - Osato Miyawaki
- Department of Food Science and Technology, Tokyo University of Marine Science and Technology , 4-5-7 Konan, Minato-ku, Tokyo 108-8477, Japan
| | - Kazuaki Matsumura
- School of Materials Science, Japan Advanced Institute of Science and Technology , Nomi, Ishikawa 923-1292, Japan
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42
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Yan Z, Hui TH, Fong HW, Shao X, Cho WC, Ngan KC, Yip TC, Lin Y. An electroporation platform for Erlotinib resistance screening in living non-small cell lung cancer (NSCLC) cells. Biomed Phys Eng Express 2018. [DOI: 10.1088/2057-1976/aa99e9] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/22/2022]
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43
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Energy dissipation mapping of cancer cells. Micron 2017; 105:24-29. [PMID: 29169143 DOI: 10.1016/j.micron.2017.11.005] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/24/2017] [Revised: 11/11/2017] [Accepted: 11/11/2017] [Indexed: 11/24/2022]
Abstract
The purpose of this study is to map the energy dissipation of Jurkat cells using a single 60 nanosecond pulse electric field (NsPEF), primarily through atomic force microscopy (AFM). The phase shift is generated by the sample elements that do not have a heterogeneous surface. Monitoring and manipulating the phase shift is a powerful way for determining the dissipated energy and plotting the topography. The dissipated energy is a relative value, so the silica wafer and cover slip are given a set reference while the transmission of energy between the tip of the cantilever and cell surfaces is measured. The most important finding is that the magnitude and the number of variations in the dissipated energy change with the strength of NsPEF applied. Utilizing a single low field strength NsPEF (15kV/cm), minor changes in dissipated energy were found. The application of a single high field strength NsPEF (60kV/cm) to Jurkat cells resulted in a higher dissipated energy change versus that of in the low field strength condition. Thus, the dissipated energy from the Jurkat cells changes with the strength of NsPEF. By analyzing the forces via investigation in the tapping mode of the AFM, the stabilization of the cytoskeleton and membrane of the cell are related to the strength of NsPEF applied. Furthermore, the strength of NsPEF indicates a meaningful relationship to the survival of the Jurkat cells.
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Guo S, Jing Y, Burcus NI, Lassiter BP, Tanaz R, Heller R, Beebe SJ. Nano-pulse stimulation induces potent immune responses, eradicating local breast cancer while reducing distant metastases. Int J Cancer 2017; 142:629-640. [PMID: 28944452 DOI: 10.1002/ijc.31071] [Citation(s) in RCA: 62] [Impact Index Per Article: 8.9] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/24/2017] [Revised: 09/12/2017] [Accepted: 09/18/2017] [Indexed: 12/22/2022]
Abstract
Nano-pulse stimulation (NPS) as a developing technology has been studied for minimally invasive, nonthermal local cancer elimination for more than a decade. Here we show that a single NPS treatment results in complete regression of the poorly immunogenic, metastatic 4T1-Luc mouse mammary carcinoma. Impressively, spontaneous distant organ metastases were largely prevented, even in those animals with incomplete tumor regression. All tumor-free mice were protected from secondary tumor cell challenge, demonstrating a vaccine-like effect. NPS treatment induced antitumor immunity, long-term memory T cells, destruction of tumor microenvironment and reversal of the massive increase of immune suppressor cells in the tumor microenvironment and blood. NPS-treated 4T1 cells exhibited release of damage-associated molecular patterns (DAMPs), including calreticulin, HMGB1 and ATP, and activated dendritic cells. Those findings suggest that NPS is a potent immunogenic cell death inducer that elicits antitumor immunity to prevent distant metastases in addition to local tumor eradication.
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Affiliation(s)
- Siqi Guo
- Frank Reidy Research Center for Bioelectrics, Old Dominion University, Norfolk, Virginia, 23508
| | - Yu Jing
- Frank Reidy Research Center for Bioelectrics, Old Dominion University, Norfolk, Virginia, 23508
| | - Niculina I Burcus
- Frank Reidy Research Center for Bioelectrics, Old Dominion University, Norfolk, Virginia, 23508
| | - Brittany P Lassiter
- Frank Reidy Research Center for Bioelectrics, Old Dominion University, Norfolk, Virginia, 23508
| | - Royena Tanaz
- Frank Reidy Research Center for Bioelectrics, Old Dominion University, Norfolk, Virginia, 23508
| | - Richard Heller
- Frank Reidy Research Center for Bioelectrics, Old Dominion University, Norfolk, Virginia, 23508
| | - Stephen J Beebe
- Frank Reidy Research Center for Bioelectrics, Old Dominion University, Norfolk, Virginia, 23508
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45
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Gianulis EC, Casciola M, Xiao S, Pakhomova ON, Pakhomov AG. Electropermeabilization by uni- or bipolar nanosecond electric pulses: The impact of extracellular conductivity. Bioelectrochemistry 2017; 119:10-19. [PMID: 28865240 DOI: 10.1016/j.bioelechem.2017.08.005] [Citation(s) in RCA: 35] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/07/2017] [Revised: 07/05/2017] [Accepted: 08/15/2017] [Indexed: 02/03/2023]
Abstract
Cellular effects caused by nanosecond electric pulses (nsEP) can be reduced by an electric field reversal, a phenomenon known as bipolar cancellation. The reason for this cancellation effect remains unknown. We hypothesized that assisted membrane discharge is the mechanism for bipolar cancellation. CHO-K1 cells bathed in high (16.1mS/cm; HCS) or low (1.8mS/cm; LCS) conductivity solutions were exposed to either one unipolar (300-ns) or two opposite polarity (300+300-ns; bipolar) nsEP (4-40kV/cm) with increasing interpulse intervals (0.1-50μs). Time-lapse YO-PRO-1 (YP) uptake revealed enhanced membrane permeabilization in LCS compared to HCS at all tested voltages. The time-dependence of bipolar cancellation was similar in both solutions, using either identical (22kV/cm) or isoeffective nsEP treatments (12 and 32kV/cm for LCS and HCS, respectively). However, cancellation was significantly stronger in LCS when the bipolar nsEP had no, or very short (<1μs), interpulse intervals. Finally, bipolar cancellation was still present with interpulse intervals as long as 50μs, beyond the time expected for membrane discharge. Our findings do not support assisted membrane discharge as the mechanism for bipolar cancellation. Instead they exemplify the sustained action of nsEP that can be reversed long after the initial stimulus.
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Affiliation(s)
- Elena C Gianulis
- Frank Reidy Research Center for Bioelectrics, Old Dominion University, Norfolk, VA 23508, USA.
| | - Maura Casciola
- Frank Reidy Research Center for Bioelectrics, Old Dominion University, Norfolk, VA 23508, USA
| | - Shu Xiao
- Frank Reidy Research Center for Bioelectrics, Old Dominion University, Norfolk, VA 23508, USA; Department of Electrical and Computer Engineering, Old Dominion University, Norfolk, VA 23508, USA
| | - Olga N Pakhomova
- Frank Reidy Research Center for Bioelectrics, Old Dominion University, Norfolk, VA 23508, USA
| | - Andrei G Pakhomov
- Frank Reidy Research Center for Bioelectrics, Old Dominion University, Norfolk, VA 23508, USA
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46
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Delivery devices for exposure of biological cells to nanosecond pulsed electric fields. Med Biol Eng Comput 2017; 56:85-97. [PMID: 28674780 DOI: 10.1007/s11517-017-1676-0] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/17/2016] [Accepted: 06/25/2017] [Indexed: 12/11/2022]
Abstract
In this paper, delivery devices for nanosecond pulsed electric field exposure of biological samples in direct contact with electrodes or isolated are presented and characterized. They are based on a modified electroporation cuvette and two transverse electromagnetic cells (TEM cells). The devices were used to apply pulses with high intensity (4.5 kV) and short durations (3 and 13 ns). The delivery devices were electromagnetically characterized in the frequency and time domains. Field intensities of around 5, 0.5, and 12 MV m-1 were obtained by numerical simulations of the biological sample positioned in the three delivery devices. Two delivery systems had a homogenous electric field spatial distribution, and one was adapted to permit a highly localized exposure in the vicinity of a needle. Experimental biological investigations were carried out at different field intensities for five cancer cell lines. The results using flow cytometry showed that cells kept polarized mitochondrial membrane but lost plasma membrane integrity following a dose-response trend after exposure to different electric field intensities. Certain cell types (U87, MCF7) showed higher sensitivities to nsPEFs than other lines tested.
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47
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Atkins RM, Fawcett TJ, Gilbert R, Hoff AM, Connolly R, Brown DW, Llewellyn AJ, Jaroszeski MJ. Impedance spectroscopy as an indicator for successful in vivo electric field mediated gene delivery in a murine model. Bioelectrochemistry 2017; 115:33-40. [DOI: 10.1016/j.bioelechem.2017.01.004] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/03/2016] [Revised: 01/20/2017] [Accepted: 01/22/2017] [Indexed: 12/19/2022]
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48
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The Electrode Modality Development in Pulsed Electric Field Treatment Facilitates Biocellular Mechanism Study and Improves Cancer Ablation Efficacy. JOURNAL OF HEALTHCARE ENGINEERING 2017; 2017:3624613. [PMID: 29065589 PMCID: PMC5438864 DOI: 10.1155/2017/3624613] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 01/25/2017] [Accepted: 03/15/2017] [Indexed: 01/04/2023]
Abstract
Pulsed electric field treatment is now widely used in diverse biological and medical applications: gene delivery, electrochemotherapy, and cancer therapy. This minimally invasive technique has several advantages over traditional ablation techniques, such as nonthermal elimination and blood vessel spare effect. Different electrodes are subsequently developed for a specific treatment purpose. Here, we provide a systematic review of electrode modality development in pulsed electric field treatment. For electrodes invented for experiment in vitro, sheet electrode and electrode cuvette, electrodes with high-speed fluorescence imaging system, electrodes with patch-clamp, and electrodes with confocal laser scanning microscopy are introduced. For electrodes invented for experiment in vivo, monopolar electrodes, five-needle array electrodes, single-needle bipolar electrode, parallel plate electrodes, and suction electrode are introduced. The pulsed electric field provides a promising treatment for cancer.
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49
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Dutta D, Palmer XL, Asmar A, Stacey M, Qian S. Nanosecond pulsed electric field induced changes in cell surface charge density. Micron 2017; 100:45-49. [PMID: 28494437 DOI: 10.1016/j.micron.2017.04.009] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/30/2017] [Revised: 04/25/2017] [Accepted: 04/25/2017] [Indexed: 10/19/2022]
Abstract
This study reports that the surface charge density changes in Jurkat cells with the application of single 60 nanosecond pulse electric fields, using atomic force microscopy. Using an atomic force microscope tip and Jurkat cells on silica in a 0.01M KCl ionic concentration, we were able to measure the interfacial forces, while also predicting surface charge densities of both Jurkat cell and silica surfaces. The most important finding is that the pulsing conditions varyingly reduced the cells' surface charge density. This offers a novel way in which to examine cellular effects of pulsed electric fields that may lead to the identification of unique mechanical responses. Compared to a single low field strength NsPEF (15kV/cm) application, exposure of Jurkat cells to a single high field strength NsPEF (60kV/cm) resulted in a further reduction in charge density and major morphological changes. The structural, physical, and chemical properties of biological cells immensely influence their electrostatic force; we were able to investigate this through the use of atomic force microscopy by measuring the surface forces between the AFM's tip and the Jurkat cells under different pulsing conditions as well as the interfacial forces in ionic concentrations.
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Affiliation(s)
- Diganta Dutta
- Physics and Astronomy, University of Nebraska at Kearney, NE, USA.
| | | | - Anthony Asmar
- Frank Reidy Research Center for Bioelectrics, Old Dominion University, Norfolk, VA, USA
| | - Michael Stacey
- Frank Reidy Research Center for Bioelectrics, Old Dominion University, Norfolk, VA, USA
| | - Shizhi Qian
- Institute of Micro & Nanotechnology, Mechanical & Aerospace Engineering Department, Old Dominion University, Norfolk, VA, USA
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50
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Robinson VS, Garner AL, Loveless AM, Neculaes VB. Calculated plasma membrane voltage induced by applying electric pulses using capacitive coupling. Biomed Phys Eng Express 2017. [DOI: 10.1088/2057-1976/aa630a] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/03/2023]
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