The Experts below are selected from a list of 360 Experts worldwide ranked by ideXlab platform
Richard Heller - One of the best experts on this subject based on the ideXlab platform.
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topical gene electrotransfer to the epidermis of hairless guinea pig by non invasive Multielectrode Array
PLOS ONE, 2013Co-Authors: Siqi Guo, Amy Donate, Gaurav Basu, Annelise Israel, Richard HellerAbstract:Topical gene delivery to the epidermis has the potential to be an effective therapy for skin disorders, cutaneous cancers, vaccinations and systemic metabolic diseases. Previously, we reported on a non-invasive Multielectrode Array (MEA) that efficiently delivered plasmid DNA and enhanced expression to the skin of several animal models by in vivo gene electrotransfer. Here, we characterized plasmid DNA delivery with the MEA in a hairless guinea pig model, which has a similar histology and structure to human skin. Significant elevation of gene expression up to 4 logs was achieved with intradermal DNA administration followed by topical non-invasive skin gene electrotransfer. This delivery produced gene expression in the skin of hairless guinea pig up to 12 to 15 days. Gene expression was observed exclusively in the epidermis. Skin gene electrotransfer with the MEA resulted in only minimal and mild skin changes. A low level of human Factor IX was detected in the plasma of hairless guinea pig after gene electrotransfer with the MEA, although a significant increase of Factor IX was obtained in the skin of animals. These results suggest gene electrotransfer with the MEA can be a safe, efficient, non-invasive skin delivery method for skin disorders, vaccinations and potential systemic diseases where low levels of gene products are sufficient.
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electro gene transfer to skin using a noninvasive Multielectrode Array
Journal of Controlled Release, 2011Co-Authors: Siqi Guo, Amy Donate, Gaurav Basu, Cathryn Lundberg, Loree C Heller, Richard HellerAbstract:Because of its large surface area and easy access for both delivery and monitoring, the skin is an attractive target for gene therapy for cutaneous diseases, vaccinations and several metabolic disorders. The critical factors for DNA delivery to the skin by electroporation (EP) are effective expression levels and minimal or no tissue damage. Here, we evaluated the non-invasive Multielectrode Array (MEA) for gene electrotransfer. For these studies we utilized a guinea pig model, which has been shown to have a similar thickness and structure to human skin. Our results demonstrate significantly increased gene expression 2 to 3 logs above injection of plasmid DNA alone over 15 days. Furthermore, gene expression could be enhanced by increasing the size of the treatment area. Transgene-expressing cells were observed exclusively in the epidermal layer of the skin. In contrast to caliper or plate electrodes, skin EP with the MEA greatly reduced muscle twitching and resulted in minimal and completely recoverable skin damage. These results suggest that EP with MEA can be an efficient and non-invasive skin delivery method with less adverse side effects than other EP delivery systems and promising clinical applications.
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evaluation of delivery conditions for cutaneous plasmid electrotransfer using a Multielectrode Array
Gene Therapy, 2011Co-Authors: Bernadette Ferraro, Siqi Guo, Amy Donate, Loree C Heller, Richard Heller, Yolmari CruzAbstract:Electroporation (EP) is a simple in vivo method to deliver normally impermeable molecules, such as plasmid DNA, to a variety of tissues. Delivery of plasmid DNA by EP to a large surface area is not practical because the distance between the electrode pairs, and therefore the applied voltage, must be increased to effectively permeabilize the cell membrane. The design of the Multielectrode Array (MEA) incorporates multiple electrode pairs at a fixed distance to allow for delivery of plasmid DNA to the skin, potentially reducing the sensation associated with in vivo EP. In this report, we evaluate the effects of field strength and pulse width on transgene expression and duration using a plasmid encoding the luciferase reporter gene delivered by intradermal injection in a guinea pig model followed by EP with the MEA. As expected, the level of luciferase expression increased with the magnitude and duration of the voltage applied. In addition to adjusting transgene expression levels by altering fielding strength, levels could also be controlled by adjusting the plasmid dose. Our results indicate that the design of the MEA is a viable option for cutaneous plasmid DNA delivery by in vivo EP to a large surface area.
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electrically mediated delivery of plasmid dna to the skin using a Multielectrode Array
Human Gene Therapy, 2010Co-Authors: Richard Heller, Loree C Heller, Yolmari Cruz, Richard Gilbert, Mark J JaroszeskiAbstract:The easy accessibility of skin makes it an excellent target for gene transfer protocols. To take full advantage of skin as a target for gene transfer, it is important to establish an efficient and reproducible delivery system. Electroporation is a strong candidate to meet this delivery criterion. Electroporation of the skin is a simple, direct, in vivo method to deliver genes for therapy. Previously, delivery to the skin was performed by means of applicators with relatively large distances between electrodes, resulting in significant muscle stimulation and pain. These applicators also had limitations in controlling the directionality of the applied field. To resolve this issue, a system consisting of an Array of electrodes that decreased the distance between them and that were independently addressable for directional control of the field was developed. This new Multielectrode Array (MEA) was compared with an established electrode. In a rat model, comparable reporter expression was seen after delivery with each electrode. Delivery was also evaluated in a guinea pig model to determine the potential of this approach in an animal model with skin thickness and structure similar to human skin. The results clearly showed that effective delivery was related to both the electrode and the parameters chosen. With the MEA, the muscle twitching associated with application of electric fields was notably reduced compared with conventional electrode systems. This is important, as it will facilitate the translation of electroporation-mediated gene delivery to skin for clinical use with DNA vaccines or for therapies for cancer or protein deficiencies.
Nicholas J Maragakis - One of the best experts on this subject based on the ideXlab platform.
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role of human induced pluripotent stem cell derived spinal cord astrocytes in the functional maturation of motor neurons in a Multielectrode Array system
Stem Cells Translational Medicine, 2019Co-Authors: Arens Taga, Raha Dastgheyb, Christa W Habela, Jessica Joseph, Jean Philippe Richard, Sarah K Gross, Giuseppe Lauria, Gabsang Lee, Norman J Haughey, Nicholas J MaragakisAbstract:The ability to generate human-induced pluripotent stem cell (hiPSC)-derived neural cells displaying region-specific phenotypes is of particular interest for modeling central nervous system biology in vitro. We describe a unique method by which spinal cord hiPSC-derived astrocytes (hiPSC-A) are cultured with spinal cord hiPSC-derived motor neurons (hiPSC-MN) in a Multielectrode Array (MEA) system to record electrophysiological activity over time. We show that hiPSC-A enhance hiPSC-MN electrophysiological maturation in a time-dependent fashion. The sequence of plating, density, and age in which hiPSC-A are cocultured with MN, but not their respective hiPSC line origin, are factors that influence neuronal electrophysiology. When compared to coculture with mouse primary spinal cord astrocytes, we observe an earlier and more robust electrophysiological maturation in the fully human cultures, suggesting that the human origin is relevant to the recapitulation of astrocyte/motor neuron crosstalk. Finally, we test pharmacological compounds on our MEA platform and observe changes in electrophysiological activity, which confirm hiPSC-MN maturation. These findings are supported by immunocytochemistry and real-time PCR studies in parallel cultures demonstrating human astrocyte mediated changes in the structural maturation and protein expression profiles of the neurons. Interestingly, this relationship is reciprocal and coculture with neurons influences astrocyte maturation as well. Taken together, these data indicate that in a human in vitro spinal cord culture system, astrocytes support hiPSC-MN maturation in a time-dependent and species-specific manner and suggest a closer approximation of in vivo conditions. Stem Cells Translational Medicine 2019;8:1272&1285.
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role of human induced pluripotent stem cell derived spinal cord astrocytes in the functional maturation of motor neurons in a Multielectrode Array system
bioRxiv, 2019Co-Authors: Arens Taga, Raha Dastgheyb, Christa W Habela, Jessica Joseph, Jean Philippe Richard, Sarah K Gross, Giuseppe Lauria, Gabsang Lee, Norman J Haughey, Nicholas J MaragakisAbstract:The ability to generate human induced pluripotent stem cell (hiPSC)-derived neural cells displaying region-specific phenotypes is of particular interest for modeling central nervous system (CNS) biology in vitro. We describe a unique method by which spinal cord hiPSC-derived astrocytes (hiPSC-A) are cultured with spinal cord hiPSC-derived motor neurons (hiPSC-MN) in a Multielectrode Array (MEA) system to record electrophysiological activity over time. We show that hiPSC-A enhance hiPSC-MN electrophysiological maturation in a time-dependent fashion. The sequence of plating, density, and age in which hiPSC-As are co-cultured with MN, but not their respective hiPSC line origin, are factors that influence neuronal electrophysiology. When compared to co-culture with mouse primary spinal cord astrocytes, we observe an earlier and more robust electrophysiological maturation in the fully human cultures, suggesting that the human origin is relevant to the recapitulation of astrocyte/motor neuron cross-talk. Finally, we test pharmacological compounds on our MEA platform and observe changes in electrophysiological activity which confirm hiPSC-MN maturation. These findings are supported by immunocytochemistry and real time PCR studies in parallel cultures demonstrating human astrocyte mediated changes in the structural maturation and protein expression profiles of the neurons. Interestingly, this relationship is reciprocal and co-culture with neurons influences astrocyte maturation as well. Taken together these data indicate that in a human in vitro spinal cord culture system, astrocytes alter hiPSC-MN maturation in a time-dependent and species specific manner and suggest a closer approximation of in vivo conditions.nnMain PointsO_LIWe developed a method for the co-culture of human iPSC-A/MN for Multielectrode Array recordings.nC_LIO_LIThe morphological, molecular, pharmacological, and electrophysiological characterization of the co-cultures suggests bidirectional maturation.nC_LI
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Role of Human-Induced Pluripotent Stem Cell-Derived Spinal Cord Astrocytes in the Functional Maturation of Motor Neurons in a Multielectrode Array System
'Wiley', 2019Co-Authors: Arens Taga, Raha Dastgheyb, Christa W Habela, Jessica Joseph, Sarah K Gross, Giuseppe Lauria, Gabsang Lee, J. Richard, N. Haughey, Nicholas J MaragakisAbstract:The ability to generate human-induced pluripotent stem cell (hiPSC)-derived neural cells displaying region-specific phenotypes is of particular interest for modeling central nervous system biology in vitro. We describe a unique method by which spinal cord hiPSC-derived astrocytes (hiPSC-A) are cultured with spinal cord hiPSC-derived motor neurons (hiPSC-MN) in a Multielectrode Array (MEA) system to record electrophysiological activity over time. We show that hiPSC-A enhance hiPSC-MN electrophysiological maturation in a time-dependent fashion. The sequence of plating, density, and age in which hiPSC-A are cocultured with MN, but not their respective hiPSC line origin, are factors that influence neuronal electrophysiology. When compared to coculture with mouse primary spinal cord astrocytes, we observe an earlier and more robust electrophysiological maturation in the fully human cultures, suggesting that the human origin is relevant to the recapitulation of astrocyte/motor neuron crosstalk. Finally, we test pharmacological compounds on our MEA platform and observe changes in electrophysiological activity, which confirm hiPSC-MN maturation. These findings are supported by immunocytochemistry and real-time PCR studies in parallel cultures demonstrating human astrocyte mediated changes in the structural maturation and protein expression profiles of the neurons. Interestingly, this relationship is reciprocal and coculture with neurons influences astrocyte maturation as well. Taken together, these data indicate that in a human in vitro spinal cord culture system, astrocytes support hiPSC-MN maturation in a time-dependent and species-specific manner and suggest a closer approximation of in vivo conditions
Evelyne Sernagor - One of the best experts on this subject based on the ideXlab platform.
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Rank order coding: a retinal information decoding strategy revealed by large-scale Multielectrode Array retinal recordings
eNeuro, 2016Co-Authors: Geoffrey Portelli, Alessandro Maccione, Stefano Di Marco, Luca Berdondini, John M. Barrett, Gerrit Hilgen, Timothée Masquelier, Pierre Kornprobst, Evelyne SernagorAbstract:How a population of retinal ganglion cells (RGCs) encodes the visual scene remains an open question. Going beyond individual RGC coding strategies, results in salamander suggest that the relative latencies of an RGC pair encodes spatial information. Thus a population code based on this concerted spiking could be a powerful mechanism to transmit visual information rapidly and efficiently. Here, we tested this hypothesis in mouse by recording simultaneous light-evoked responses from hundreds of RGCs, at pan-retinal level, using a new generation of large-scale, high density Multielectrode Array consisting of 4096 electrodes. Interestingly, we did not find any RGCs exhibiting a clear latency tuning to the stimuli, suggesting that in mouse, individual RGC pairs may not provide sufficient information. We show that a significant amount of information is encoded synergistically in the concerted spiking of large RGC populations. Thus, the RGC population response described with relative activities, or ranks, provides more relevant information than classical independent spike count- or latency- based codes. In particular, we report for the first time that when considering the relative activities across the whole population, the wave of first stimulus-evoked spikes (WFS) is an accurate indicator of stimulus content. We show that this coding strategy co-exists with classical neural codes, and that it is more efficient and faster. Overall, these novel observations suggest that already at the level of the retina, concerted spiking provides a reliable and fast strategy to rapidly transmit new visual scenes.
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a data repository and analysis framework for spontaneous neural activity recordings in developing retina
GigaScience, 2014Co-Authors: Stephen J Eglen, Michael Weeks, Mark Jessop, Jennifer Simonotto, Thomas Jackson, Evelyne SernagorAbstract:During early development, neural circuits fire spontaneously, generating activity episodes with complex spatiotemporal patterns. Recordings of spontaneous activity have been made in many parts of the nervous system over the last 25 years, reporting developmental changes in activity patterns and the effects of various genetic perturbations. We present a curated repository of Multielectrode Array recordings of spontaneous activity in developing mouse and ferret retina. The data have been annotated with minimal metadata and converted into HDF5. This paper describes the structure of the data, along with examples of reproducible research using these data files. We also demonstrate how these data can be analysed in the CARMEN workflow system. This article is written as a literate programming document; all programs and data described here are freely available. 1. We hope this repository will lead to novel analysis of spontaneous activity recorded in different laboratories. 2. We encourage published data to be added to the repository. 3. This repository serves as an example of how Multielectrode Array recordings can be stored for long-term reuse.
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a data repository and analysis framework for spontaneous neural activity recordings in developing retina
bioRxiv, 2013Co-Authors: Stephen J Eglen, Michael Weeks, Mark Jessop, Jennifer Simonotto, Thomas Jackson, Evelyne SernagorAbstract:Background: During early development, neural circuits fire spontaneously, generating activity episodes with complex spatiotemporal patterns. Recordings of spontaneous activity have been made in many parts of the nervous system over the last 20 years, reporting developmental changes in activity patterns and the effects of various genetic perturbations. Results: We present a curated repository of Multielectrode Array recordings of spontaneous activity in developing mouse and ferret retina. The data have been annotated with minimal metadata and converted into the HDF5 format. This paper describes the structure of the data, along with examples of reproducible research using these data files. We also demonstrate how these data can be analysed in the CARMEN workflow system. This article is written as a literate programming document; all programs and data described here are freely available. Conclusions: 1. We hope this repository will lead to novel analysis of spontaneous activity recorded in different laboratories. 2. We encourage published data to be added to the repository. 3. This repository serves as an example of how Multielectrode Array recordings can be stored for long-term reuse.
Lietai Yang - One of the best experts on this subject based on the ideXlab platform.
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threshold chloride levels for localized carbon steel corrosion in simulated concrete pore solutions using coupled Multielectrode Array sensors
Corrosion, 2014Co-Authors: Lietai Yang, Roberto T Pabalan, K T Chiang, Biswajit Dasgupta, Luis IbarraAbstract:Threshold chloride levels for localized corrosion of carbon steel material have been studied in three types of simulated concrete pore solutions: sodium hydroxide-potassium hydroxide (NaOH-KOH) with pH 11.6, calcium hydroxide (Ca[OH]2) with pH 12.6, and sodium hydroxide-potassium hydroxide-calcium hydroxide (NaOH-KOH-Ca[OH]2) with pH 13.3. The nonuniform corrosion rates of carbon steel were measured with coupled Multielectrode Array sensors (CMAS) when the chloride concentration was changed from 0.0005 mol/L to 1 mol/L in each solution. Open-circuit potentials were also measured from the coupling joint of the CMAS probes and electrodes made of rebar specimens immersed in the simulated pore solutions to verify the results from the CMAS probes.
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Corrosion Behavior of Carbon Steel and Stainless Steel Materials under Salt Deposits in Simulated Dry Repository Environments
MRS Proceedings, 2011Co-Authors: Lietai Yang, Lauren Browning, Roberto T Pabalan, Darrell S DunnAbstract:In-situ coupled Multielectrode Array sensors were used to measure the non-uniform corrosion of carbon steel and stainless steel materials under KCl salt deposit in simulated dry repository environments. It was found that the initiation of non-uniform corrosion occurs at a relative humidity that is 14% lower than the deliquescence relative humidity of the chloride salt. It was found also that once significant corrosion had occurred, the non-uniform corrosion process for the carbon steel material under the salt deposit continues at relative humidities as low as 27%.
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internal current effects on localized corrosion rate measurements using coupled Multielectrode Array sensors
Corrosion, 2010Co-Authors: Lietai Yang, Kuangtsan Kenneth Chiang, Pavan K Shukla, Nobuo ShiratoriAbstract:Abstract Coupled Multielectrode Array sensors (CMAS) have been used for real-time monitoring of corrosion, particularly localized corrosion. The internal anodic current on the most anodic electrode...
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a review of coupled Multielectrode Array sensors for corrosion monitoring and a study on the behaviors of the anodic and cathodic electrodes
Journal of Astm International, 2009Co-Authors: Lietai Yang, K T ChiangAbstract:Localized corrosion is often the cause of many failures and unplanned shutdowns in industry. For example, statistics have shown that more than 80 % of the corrosion-induced failures in the chemical processing industry are due to localized corrosion, rather than general corrosion. Thanks to the advancement in coupled Multielectrode Array sensors (CMAS) technology, localized corrosion rates can now be quantitatively measured. If interfaced with controllers, CMAS probes can be used to automatically control the dosing of corrosion inhibitors and reduce the cost for corrosion control. This paper presents an overview for the CMAS technology and the experimental data that verifies the working principles of the CMAS for localized corrosion rate measurement.
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development of crevice free electrodes for Multielectrode Array sensors for applications at high temperatures
Corrosion, 2008Co-Authors: K T Chiang, Lietai YangAbstract:Abstract Coupled Multielectrode Array sensors (CMAS) have been used as online and real-time monitors for localized corrosion in both laboratory and field systems. In a CMAS probe, multiple miniature electrodes made of materials identical to the engineering component are used as sensing electrodes. The application of CMAS at high temperatures, up to 150°C in corrosive environments, however, is limited by degradation of the insulating mounting material, such as epoxy. Degradation of the mounting material can lead to crevice corrosion and causes an increase in the exposed surface area of the electrodes. In this study, the effectiveness of a diamond-like carbon film to protect the Alloy 22 (UNS N06022) electrodes in an acidic sodium chloride-sodium nitrate-potassium nitrate (NaCl-NaNO3-KNO3) salt mixture was demonstrated at 150°C. The average localized corrosion rate measured from the probe with coated electrodes in the NaCl-NaNO3-KNO3 salt mixture at 150°C was approximately 0.43 μm/y. In contrast, the averag...
Arens Taga - One of the best experts on this subject based on the ideXlab platform.
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role of human induced pluripotent stem cell derived spinal cord astrocytes in the functional maturation of motor neurons in a Multielectrode Array system
Stem Cells Translational Medicine, 2019Co-Authors: Arens Taga, Raha Dastgheyb, Christa W Habela, Jessica Joseph, Jean Philippe Richard, Sarah K Gross, Giuseppe Lauria, Gabsang Lee, Norman J Haughey, Nicholas J MaragakisAbstract:The ability to generate human-induced pluripotent stem cell (hiPSC)-derived neural cells displaying region-specific phenotypes is of particular interest for modeling central nervous system biology in vitro. We describe a unique method by which spinal cord hiPSC-derived astrocytes (hiPSC-A) are cultured with spinal cord hiPSC-derived motor neurons (hiPSC-MN) in a Multielectrode Array (MEA) system to record electrophysiological activity over time. We show that hiPSC-A enhance hiPSC-MN electrophysiological maturation in a time-dependent fashion. The sequence of plating, density, and age in which hiPSC-A are cocultured with MN, but not their respective hiPSC line origin, are factors that influence neuronal electrophysiology. When compared to coculture with mouse primary spinal cord astrocytes, we observe an earlier and more robust electrophysiological maturation in the fully human cultures, suggesting that the human origin is relevant to the recapitulation of astrocyte/motor neuron crosstalk. Finally, we test pharmacological compounds on our MEA platform and observe changes in electrophysiological activity, which confirm hiPSC-MN maturation. These findings are supported by immunocytochemistry and real-time PCR studies in parallel cultures demonstrating human astrocyte mediated changes in the structural maturation and protein expression profiles of the neurons. Interestingly, this relationship is reciprocal and coculture with neurons influences astrocyte maturation as well. Taken together, these data indicate that in a human in vitro spinal cord culture system, astrocytes support hiPSC-MN maturation in a time-dependent and species-specific manner and suggest a closer approximation of in vivo conditions. Stem Cells Translational Medicine 2019;8:1272&1285.
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role of human induced pluripotent stem cell derived spinal cord astrocytes in the functional maturation of motor neurons in a Multielectrode Array system
bioRxiv, 2019Co-Authors: Arens Taga, Raha Dastgheyb, Christa W Habela, Jessica Joseph, Jean Philippe Richard, Sarah K Gross, Giuseppe Lauria, Gabsang Lee, Norman J Haughey, Nicholas J MaragakisAbstract:The ability to generate human induced pluripotent stem cell (hiPSC)-derived neural cells displaying region-specific phenotypes is of particular interest for modeling central nervous system (CNS) biology in vitro. We describe a unique method by which spinal cord hiPSC-derived astrocytes (hiPSC-A) are cultured with spinal cord hiPSC-derived motor neurons (hiPSC-MN) in a Multielectrode Array (MEA) system to record electrophysiological activity over time. We show that hiPSC-A enhance hiPSC-MN electrophysiological maturation in a time-dependent fashion. The sequence of plating, density, and age in which hiPSC-As are co-cultured with MN, but not their respective hiPSC line origin, are factors that influence neuronal electrophysiology. When compared to co-culture with mouse primary spinal cord astrocytes, we observe an earlier and more robust electrophysiological maturation in the fully human cultures, suggesting that the human origin is relevant to the recapitulation of astrocyte/motor neuron cross-talk. Finally, we test pharmacological compounds on our MEA platform and observe changes in electrophysiological activity which confirm hiPSC-MN maturation. These findings are supported by immunocytochemistry and real time PCR studies in parallel cultures demonstrating human astrocyte mediated changes in the structural maturation and protein expression profiles of the neurons. Interestingly, this relationship is reciprocal and co-culture with neurons influences astrocyte maturation as well. Taken together these data indicate that in a human in vitro spinal cord culture system, astrocytes alter hiPSC-MN maturation in a time-dependent and species specific manner and suggest a closer approximation of in vivo conditions.nnMain PointsO_LIWe developed a method for the co-culture of human iPSC-A/MN for Multielectrode Array recordings.nC_LIO_LIThe morphological, molecular, pharmacological, and electrophysiological characterization of the co-cultures suggests bidirectional maturation.nC_LI
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Role of Human-Induced Pluripotent Stem Cell-Derived Spinal Cord Astrocytes in the Functional Maturation of Motor Neurons in a Multielectrode Array System
'Wiley', 2019Co-Authors: Arens Taga, Raha Dastgheyb, Christa W Habela, Jessica Joseph, Sarah K Gross, Giuseppe Lauria, Gabsang Lee, J. Richard, N. Haughey, Nicholas J MaragakisAbstract:The ability to generate human-induced pluripotent stem cell (hiPSC)-derived neural cells displaying region-specific phenotypes is of particular interest for modeling central nervous system biology in vitro. We describe a unique method by which spinal cord hiPSC-derived astrocytes (hiPSC-A) are cultured with spinal cord hiPSC-derived motor neurons (hiPSC-MN) in a Multielectrode Array (MEA) system to record electrophysiological activity over time. We show that hiPSC-A enhance hiPSC-MN electrophysiological maturation in a time-dependent fashion. The sequence of plating, density, and age in which hiPSC-A are cocultured with MN, but not their respective hiPSC line origin, are factors that influence neuronal electrophysiology. When compared to coculture with mouse primary spinal cord astrocytes, we observe an earlier and more robust electrophysiological maturation in the fully human cultures, suggesting that the human origin is relevant to the recapitulation of astrocyte/motor neuron crosstalk. Finally, we test pharmacological compounds on our MEA platform and observe changes in electrophysiological activity, which confirm hiPSC-MN maturation. These findings are supported by immunocytochemistry and real-time PCR studies in parallel cultures demonstrating human astrocyte mediated changes in the structural maturation and protein expression profiles of the neurons. Interestingly, this relationship is reciprocal and coculture with neurons influences astrocyte maturation as well. Taken together, these data indicate that in a human in vitro spinal cord culture system, astrocytes support hiPSC-MN maturation in a time-dependent and species-specific manner and suggest a closer approximation of in vivo conditions