Journal: HardwareX

Article Title: A modular and flexible open source cell incubator system for mobile and stationary use

doi: 10.1016/j.ohx.2024.e00571

Figure Lengend Snippet: Overview of the inkubox system intended for long-term electrophysiological experiments. Here, the incubator system is comprised of a control unit and an incubation chamber called “inkubox”. The incubation chamber provides space for four MaxOne headstages used to obtain neural recordings from CMOS MEAs. The headstages are connected to MaxOne hubs (recording units) via LAN connectors through the inkubox wall, allowing the hubs to be stationed outside of the controlled incubation environment.

Article Snippet: Four recording units (MaxOne, Maxwell Biosystems, Switzerland) for complementary metal–oxide–semiconductor (CMOS) microelectrode arrays (MEA) can be placed within the inkubox chamber for parallel recordings of four neural cultures in a stable environment.

Techniques: Control, Incubation

Journal: bioRxiv

Article Title: Electrophysiological Phenotype Characterization of Human iPSC-Derived Neuronal Cell Lines by Means of High-Density Microelectrode Arrays

doi: 10.1101/2020.09.02.271403

Figure Lengend Snippet: (a) HD-MEA electrical image showing 2D spatial distribution maps of the electrode firing rate (eFR, see Methods, HD-MEA Metrics) as recorded across the entire HD-MEA chip surface from 6’600 electrodes at DIV 21, for rat primary cortical neurons (rPCNs), human motor neurons (hMNs) and human dopaminergic neurons (hDNs). (b) Microscope image of MAP-2 positive (red) stained neurons on HD-MEA chips. Cells were fixed and stained on the HD-MEA chips at DIV 21. (c) Cell-type specific stainings of cultures on HD-MEA chips shown in . Cell nuclei are shown in blue (Hoechst positive), motor neurons (SMI-32 positive) and dopaminergic neurons (TH positive) in yellow, astrocytes (GFAP, S100-β positive) in green. (d) Example voltage traces showing extracellular action potentials (spikes) recorded by two electrodes at DIV 21. Left panel: rat primary cortical neurons. Central panel: human motor neurons. Right panel: human dopaminergic neurons.

Article Snippet: We mostly used the MaxOne HD-MEA produced by MaxWell Biosystems AG ( www.mxwbio.com ).

Techniques: Microscopy, Staining

Journal: bioRxiv

Article Title: Electrophysiological Phenotype Characterization of Human iPSC-Derived Neuronal Cell Lines by Means of High-Density Microelectrode Arrays

doi: 10.1101/2020.09.02.271403

Figure Lengend Snippet: (a) Exemplary 2D spatial distribution maps (6’600 electrodes) of electrode firing rates for motor neurons (top) and dopaminergic neurons (bottom), at DIVs 7, 14 and 21, respectively. (b) Bar plots comparing the mean firing rate (MFR), mean spike amplitude (MSA), mean ISI coefficient of variation (ISIcv) and percentage of active electrodes (pAE) of 12 hMN cultures (blue) and 17 hDN cultures (red) at DIVs 7, 14 and 21. (c) Bar plots comparing the mean firing rate, mean spike amplitude, mean ISI coefficient of variation and percentage of active electrodes of 12 hMN cultures (blue) and 15 hMN-ALS cultures (light blue) at DIVs 7, 14 and 21. (d) Bar plots comparing the mean firing rate, mean spike amplitude, mean ISI coefficient of variation and percentage of active electrodes of 17 hDN cultures (red) and 16 hDN-PD cultures (orange) at DIVs 7, 14 and 21. Each dot represents one HD-MEA or well. Bar heights indicate distribution mean values, and error bars indicate standard deviations. The black stars indicate p values: * p < 0.05, ** p < 0.01, *** p < 0.001, **** p < 0.0001.

Article Snippet: We mostly used the MaxOne HD-MEA produced by MaxWell Biosystems AG ( www.mxwbio.com ).

Techniques:

Journal: bioRxiv

Article Title: Electrophysiological Phenotype Characterization of Human iPSC-Derived Neuronal Cell Lines by Means of High-Density Microelectrode Arrays

doi: 10.1101/2020.09.02.271403

Figure Lengend Snippet: (a) Population spike time histograms simultaneously recorded by 1’024 electrodes from hMN (blue), hMN-ALS (light blue), hDN (red) and hDN-PD (orange) neurons at DIV 21. (b) Bar plots comparing mean burst duration (BD), mean inter-burst interval (IBI) and mean IBI coefficient of variation (IBIcv) of 9 hMN cultures (blue) and 18 hDN cultures (red) at DIVs 14 and DIV 21. Each dot represents one HD-MEA or well. (c) Bar plots comparing mean burst duration, mean IBI and mean IBI coefficient of variation of 9 hMN cultures (blue) and 10 hMN-ALS cultures (light blue) at DIV 14 and DIV 21. Each dot represents one HD-MEA or well. (d) Bar plots comparing mean burst duration, mean IBI and mean IBI coefficient of variation of 18 hDN cultures (red) and 16 hDN-PD cultures (orange) at DIV 14 and DIV 21. Each dot represents one HD-MEA or well. Bar heights indicate distribution mean values, and error bar indicate standard deviations. The black stars indicate p values: * p < 0.05, ** p < 0.01, *** p < 0.001, **** p < 0.0001.

Article Snippet: We mostly used the MaxOne HD-MEA produced by MaxWell Biosystems AG ( www.mxwbio.com ).

Techniques:

Journal: bioRxiv

Article Title: Electrophysiological Phenotype Characterization of Human iPSC-Derived Neuronal Cell Lines by Means of High-Density Microelectrode Arrays

doi: 10.1101/2020.09.02.271403

Figure Lengend Snippet: ( a ) Population spike time histograms simultaneously recorded by 1’024 electrodes from (from left to right) hMN (blue), hMN-ALS (light blue), hDN (red), hDN-PD (orange) neurons at DIV 14 (top) and DIV 21 (bottom). At the left of each panel, an average network burst template is shown for the specific DIV and related neuronal cell type. (b) Bar plots comparing the Pearson Correlation Coefficient (PCC) upon linearly correlating the recorded network bursts to the corresponding average templates represented in the top panel. The graph represents the PCC upon linearly correlating burst of healthy motor neurons (N=9) and ALS motor neurons (N=10) to the template obtained from the healthy motor neurons at DIVs 14 and 21. Each dot represents one HD-MEA or well. Box plots indicate distribution mean value and standard deviation. (c) PCCs for correlating the hMN-ALS template to bursts of hMN (N=9) and hMN-ALS (N=10) lines. (d) PCCs for correlating the hDN template to burst of hDN (N=18) and hDN-PD (N=16) lines. (e) PCCs for correlating the hDN-PD template to bursts of hDN (N=18) and hDN-PD (N=16) lines. The black stars indicate p values: * p < 0.05, ** p < 0.01, *** p < 0.001, **** p < 0.0001.

Article Snippet: We mostly used the MaxOne HD-MEA produced by MaxWell Biosystems AG ( www.mxwbio.com ).

Techniques: Standard Deviation

Journal: bioRxiv

Article Title: Electrophysiological Phenotype Characterization of Human iPSC-Derived Neuronal Cell Lines by Means of High-Density Microelectrode Arrays

doi: 10.1101/2020.09.02.271403

Figure Lengend Snippet: (a) Spatial distribution of action potential (AP) waveforms of sample neurons of (top to bottom) hMN, hMN-ALS, hDN, hDN-PD neuronal lines. Each trace represents a cutout of 6 ms of extracellular voltage signal recorded on the respective electrode at DIV 28. The red traces indicate the waveforms on the electrode featuring the largest signal amplitude. The plots are also displayed in Figure S3 at larger magnification. (b) AP propagation in time and space, after temporal alignment of the signals of selected readout electrodes represented in (a). Points indicate the voltage minima of the recorded traces. The traces are ordered with respect to delay from top to bottom with the top trace featuring the longest delay and coming from the electrode that is most distant to the axonal initial segment (AIS). (c) Linear regression interpolation to compute the AP propagation velocity for the neurons represented in (a) and (b). (d) Bar plots comparing the AP propagation velocity of (left) healthy motor neurons and ALS motor neurons and of (right) healthy and PD dopaminergic neurons, at DIVs 14, 28 and 42. Each dot represents one HD-MEA or well. Bar heights indicate distribution mean values, and error bars indicate standard deviations. Statistical significance is indicated using black stars to compare hMN and hMN-ALS neurons, blue stars to compare hMNs at different DIVs and light blue stars to compare hMN-ALS neurons at different DIVs. The stars indicate p values: * p < 0.05 and ** p < 0.01. The number (N) of hMNs for which velocities were determined at DIVs 14, 28 and 42 is 40, 165 and 80, respectively. The number (N) of hMN-ALSs for which velocities were determined at DIV 14, 28 and 42 is 11, 92 and 76, respectively. The number (N) of hDNs for which velocities were determined at DIVs 28 and 42 is 11 and 17, respectively. The number (N) of hDN-PDs for which velocities were determined at DIVs 14, 28 and 42 is 3, 19 and 14, respectively.

Article Snippet: We mostly used the MaxOne HD-MEA produced by MaxWell Biosystems AG ( www.mxwbio.com ).

Techniques:

Journal: bioRxiv

Article Title: Electrophysiological Phenotype Characterization of Human iPSC-Derived Neuronal Cell Lines by Means of High-Density Microelectrode Arrays

doi: 10.1101/2020.09.02.271403

Figure Lengend Snippet: (a) 2D spatial distribution maps of electrode spike rates recorded from four exemplary HD-MEAs at DIV 14. Signals from 6’600 electrodes per HD-MEA were recorded before drug administration (top row) and one minute after drug administration (bottom row) for different retigabine concentrations. (b) Bar plots representing the relative change (percent) in active electrodes for each applied retigabine concentration and for the vehicle control with respect to pre-treatment conditions. Each dot represents one HD-MEA or well. Bar heights indicate distribution mean values and error bars indicate standard deviations. The dashed gray line marks the values (100%) before drug treatment. The number of HD-MEAs or wells included N=4 for vehicle control and N=5 for each retigabine concentration (1 μM, 5 μM and 10 μM). (c) Population spike time histograms of four representative HD-MEAs, recorded before (top row) and after drug administration (bottom row) for different retigabine concentrations. (d) Bar plots representing the relative change in the mean IBI for each applied retigabine concentration and for the vehicle control, normalized to pre-treatment conditions. (e) Bar plots representing the relative change in axonal velocity upon exposure to the vehicle control (N=8 neurons), 1 μM of retigabine (N=10 neurons) and 5 μM of retigabine (N=9 neurons), normalized to pre-treatment conditions. (f) Spikes/min-values computed as relative change with respect to the situation before drug administration. Plots show spikes/min-values for using signals from the 1’020 most active electrodes at a minimum pitch of 35 μm selected from the overall array of 26’400 electrodes (left), and configurations of 64 electrodes (center) and 16 electrodes at 200 μm pitch (right). For more details, see also Supplemental . The black stars indicate p values with respect to vehicle control. Light blue stars indicate p values between 5 μM and 10 μM retigabine concentrations. * p < 0.05, ** p < 0.01.

Article Snippet: We mostly used the MaxOne HD-MEA produced by MaxWell Biosystems AG ( www.mxwbio.com ).

Techniques: Concentration Assay