Modelling and Differential Quantification of Electric Cell-Substrate Impedance Sensing Growth Curves

Measurement of cell surface coverage has become a common technique for the assessment of growth behavior of cells. As an indirect measurement method, this can be accomplished by monitoring changes in electrode impedance, which constitutes the basis of electric cell-substrate impedance sensing (ECIS). ECIS typically yields growth curves where impedance is plotted against time, and changes in single cell growth behavior or cell proliferation can be displayed without significantly impacting cell physiology. To provide better comparability of ECIS curves in different experimental settings, we developed a large toolset of R scripts for their transformation and quantification. They allow importing growth curves generated by ECIS systems, edit, transform, graph and analyze them while delivering quantitative data extracted from reference points on the curve. Quantification is implemented through three different curve fit algorithms (smoothing spline, logistic model, segmented regression). From the obtained models, curve reference points such as the first derivative maximum, segmentation knots and area under the curve are then extracted. The scripts were tested for general applicability in real-life cell culture experiments on partly anonymized cell lines, a calibration setup with a cell dilution series of impedance versus seeded cell number and finally IPEC-J2 cells treated with 1% and 5% ethanol.

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Electric Cell-Substrate Impedance Sensing To Monitor Viral Growth and Study Cellular Responses to Infection with Alphaherpesviruses in Real Time

mSphere ◽

10.1128/msphere.00039-17 ◽

2017 ◽

Vol 2 (2) ◽

Cited By ~ 13

Author(s):

Matthew R. Pennington ◽

Gerlinde R. Van de Walle

Keyword(s):

Real Time ◽

Cellular Response ◽

Cellular Responses ◽

Cellular Damage ◽

Impedance Sensing ◽

Novel Technologies ◽

Antiviral Therapies ◽

Mucosal Surfaces ◽

Cell Substrate ◽

Hsv 1

ABSTRACT Alphaherpesviruses, including those that commonly infect humans, such as HSV-1 and HSV-2, typically infect and cause cellular damage to epithelial cells at mucosal surfaces, leading to disease. The development of novel technologies to study the cellular responses to infection may allow a more complete understanding of virus replication and the creation of novel antiviral therapies. This study demonstrates the use of ECIS to study various aspects of herpesvirus biology, with a specific focus on changes in cellular morphology as a result of infection. We conclude that ECIS represents a valuable new tool with which to study alphaherpesvirus infections in real time and in an objective and reproducible manner. Electric cell-substrate impedance sensing (ECIS) measures changes in an electrical circuit formed in a culture dish. As cells grow over a gold electrode, they block the flow of electricity and this is read as an increase in electrical impedance in the circuit. ECIS has previously been used in a variety of applications to study cell growth, migration, and behavior in response to stimuli in real time and without the need for cellular labels. Here, we demonstrate that ECIS is also a valuable tool with which to study infection by alphaherpesviruses. To this end, we used ECIS to study the kinetics of cells infected with felid herpesvirus type 1 (FHV-1), a close relative of the human alphaherpesviruses herpes simplex virus 1 (HSV-1) and HSV-2, and compared the results to those obtained with conventional infectivity assays. First, we demonstrated that ECIS can easily distinguish between wells of cells infected with different amounts of FHV-1 and provides information about the cellular response to infection. Second, we found ECIS useful in identifying differences between the replication kinetics of recombinant DsRed Express2-labeled FHV-1, created via CRISPR/Cas9 genome engineering, and wild-type FHV-1. Finally, we demonstrated that ECIS can accurately determine the half-maximal effective concentration of antivirals. Collectively, our data show that ECIS, in conjunction with current methodologies, is a powerful tool that can be used to monitor viral growth and study the cellular response to alphaherpesvirus infection. IMPORTANCE Alphaherpesviruses, including those that commonly infect humans, such as HSV-1 and HSV-2, typically infect and cause cellular damage to epithelial cells at mucosal surfaces, leading to disease. The development of novel technologies to study the cellular responses to infection may allow a more complete understanding of virus replication and the creation of novel antiviral therapies. This study demonstrates the use of ECIS to study various aspects of herpesvirus biology, with a specific focus on changes in cellular morphology as a result of infection. We conclude that ECIS represents a valuable new tool with which to study alphaherpesvirus infections in real time and in an objective and reproducible manner.

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Electrical cell-substrate impedance sensing as a non-invasive tool for cancer cell study

The Analyst ◽

10.1039/c0an00560f ◽

2011 ◽

Vol 136 (2) ◽

pp. 237-245 ◽

Cited By ~ 109

Author(s):

Jongin Hong ◽

Karthikeyan Kandasamy ◽

Mohana Marimuthu ◽

Cheol Soo Choi ◽

Sanghyo Kim

Keyword(s):

Cancer Cell ◽

Impedance Sensing ◽

Non Invasive ◽

Cell Substrate ◽

Cell Study

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Comparison of Leading Biosensor Technologies to Detect Changes in Human Endothelial Barrier Properties in Response to Pro-Inflammatory TNFα and IL1β in Real-Time

Biosensors ◽

10.3390/bios11050159 ◽

2021 ◽

Vol 11 (5) ◽

pp. 159

Author(s):

James J. W. Hucklesby ◽

Akshata Anchan ◽

Simon J. O'Carroll ◽

Charles P. Unsworth ◽

E. Scott Graham ◽

...

Keyword(s):

Human Brain ◽

Real Time ◽

Barrier Properties ◽

Endothelial Barrier ◽

Endothelial Monolayer ◽

Impedance Sensing ◽

Endothelial Monolayers ◽

Impedance Data ◽

Cell Substrate ◽

Limited Frequency

Electric Cell-Substrate Impedance Sensing (ECIS), xCELLigence and cellZscope are commercially available instruments that measure the impedance of cellular monolayers. Despite widespread use of these systems individually, direct comparisons between these platforms have not been published. To compare these instruments, the responses of human brain endothelial monolayers to TNFα and IL1β were measured on all three platforms simultaneously. All instruments detected transient changes in impedance in response to the cytokines, although the response magnitude varied, with ECIS being the most sensitive. ECIS and cellZscope were also able to attribute responses to particular endothelial barrier components by modelling the multifrequency impedance data acquired by these instruments; in contrast the limited frequency xCELLigence data cannot be modelled. Consistent with its superior impedance sensing, ECIS exhibited a greater capacity than cellZscope to distinguish between subtle changes in modelled endothelial monolayer properties. The reduced resolving ability of the cellZscope platform may be due to its electrode configuration, which is necessary to allow access to the basolateral compartment, an important advantage of this instrument. Collectively, this work demonstrates that instruments must be carefully selected to ensure they are appropriate for the experimental questions being asked when assessing endothelial barrier properties.

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