Name: an enzyme- and serum-free neural stem cell culture model for emt investigation suited for drug discovery
Uploaded: 2016-08-23T13:00:00
Description: Watch this Scientific Journal Video about An Enzyme- and Serum-free Neural Stem Cell Culture Model for EMT Investigation Suited for Drug Discovery at JoVE.com

The study was supported by the University of Basel Science Foundation and the Swiss National Science Foundation by a grant to MHS and AG (SNF IZLIZ3_157230). We thank: Dr. Tania Rinaldi Burkat for generously providing infrastructure; all members of the Bettler group for discussions and comments. We thank Gerhard Dorne (Leica Microsystems, Switzerland) for professional and competent installation of the Full HD MC170 video camera (Leica Microsystems, Switzerland).

All animal procedures followed the &#39;Guide for the Care and Use of Laboratory Animals&#39; (NIH publication, 8th edition, 2011) and were approved by the Animal Welfare Committee of Basel (Swiss Guidelines for the Care and Use of Animals). By these guidelines the animal protocol is considered of &#34;lowest animal severity grade&#34;.
1. Preparation of Expansion Medium
Note: Work in aseptic conditions as standard for tissue culture.
<ol>
	<li>Take two 15 ml tubes, and add 5 ml of L-glutamine-...

<ol>
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In this study a standardized system for EMT analysis utilizing NSCs is described (summarized in Supplementary Figure 3). The standardization ensures reproducibility (Table 1 and 2). The NSCs are derived from the developing cortex, a tissue that normally does not undergo EMT. This is of advantage for the analysis of early steps in EMT. Initial steps in EMT cannot be adequately studied in tumor cells that have accumulated genetic changes and may have already adopted EMT features. Moreover,...

During several stages of embryonic development, epithelial cells lose their strong adherence to each other (e.g., tight junctions) and acquire a migratory phenotype in a process called epithelial to mesenchymal transition (EMT)1. EMT is required for the formation of additional cell types, such as the mesenchymal neural crest cells, a population that segregates from the neuroepithelium2. EMT is not only essential during embryonic stages but also required at later stages of adult life to maintain physiological processes in the adult organism, such as wound healing3and central nervous system (CNS) regeneration in demyelinating lesions4.
Epithelial tumors are known to reactivate EMT as an initiation step for migration, invasion and metastasis, ultimately leading to cancer progression1,3. EMT is indeed centrally linked to strong migration1,3. The cellular steps of conditioning, initiating, undergoing and maintaining EMT are not fully understood and need further investigation.
Here, a standardized in vitro EMT model system based on NSCs, with defined growth factors and media (no serum and no enzyme usage) is presented. This model system is of relevance for scientists working on EMT. The Snail, Zeb and Twist protein families have been shown to be critical for EMT both in development and disease1. The Snail, Zeb and Twist families are also involved in the presented system. The system is based on a specific region of the forebrain that normally does not undergo EMT providing a particular advantage for the study of initial events during EMT induction.
The model system could potentially be applied to study EMT in epithelia outside the CNS, since key EMT inducers, such as the Snail, Zeb and Twist proteins, are also found during EMT in tissue systems outside the CNS. This model system allows the standardized isolation of NSCs from the developing cortex to study stem cell features in general and EMT in particular. Using this system, we isolated NSCs, induced EMT and studied the subsequent migration under the effect of FGF2 and BMP4. We observed that FGF- and BMP-signaling interacts with TGF&#946;-signaling to promote cell migration, thus validating the model system.

<table border="1" fo:keep-together.within-page="1" fo:keep-with-next.within-page="always">
	<tbody>
		<tr>
			<td>BMP4, rhBMP4</td>
			<td>RnD Systems&#160;</td>
			<td>314-BP-01M</td>
			<td></td>
		</tr>
		<tr>
			<td>Bovine pancreas insulin</td>
			<td>Sigma&#160;</td>
			<td>I1882</td>
			<td></td>
		</tr>
		<tr>
			<td>Boyden chamber, CytoSelect cell invasion assay</td>
			<td>Cell Biolabs</td>
			<td>CBA-110</td>
			<td>24 well plate system</td>
		</tr>
		<tr>
			<td>Cell culture dish with grid</td>
			<td>Ibidi 500 mm dish, 35 mm</td>
			<td>80156</td>
			<td></td>
		</tr>
		<tr>
			<td>CellMask Orange</td>
			<td>Life Technologies</td>
			<td>C10045</td>
			<td>Plasma membrane dye, use at 1:1000 .</td>
		</tr>
		<tr>
			<td>DAPI</td>
			<td>LifeTechnologies</td>
			<td>D1306</td>
			<td>Stock at 5mg/ml. Use at 1:10000. Cancerogenic. Appropriate protection (gloves, coat, goggles) required.</td>
		</tr>
		<tr>
			<td>DMEM/F12 1:1 medium bottle</td>
			<td>Gibco Invitrogen</td>
			<td>21331-020</td>
			<td></td>
		</tr>
		<tr>
			<td>FGF2, rhFGF2</td>
			<td>RnD Systems</td>
			<td>233-FB-01M</td>
			<td></td>
		</tr>
		<tr>
			<td>Fibronectine, bovine</td>
			<td>Sigma&#160;</td>
			<td>F4759</td>
			<td></td>
		</tr>
		<tr>
			<td>Glutamax supplement&#160;</td>
			<td>Gibco Invitrogen&#160;</td>
			<td>35050-061</td>
			<td></td>
		</tr>
		<tr>
			<td>Graphics software with pixel measurement feature</td>
			<td>Fiji</td>
			<td>fiji.sc/Fiji</td>
			<td>version 2.0.0-rc-30/1.49s</td>
		</tr>
		<tr>
			<td>HBSS media</td>
			<td>Sigma&#160;</td>
			<td>H9394</td>
			<td></td>
		</tr>
		<tr>
			<td>Human apo-Transferrin</td>
			<td>Sigma</td>
			<td>T1147</td>
			<td>Possible lung irritant. Avoid inhalation. Use appropriate protection.</td>
		</tr>
		<tr>
			<td>L-glutamine</td>
			<td>Gibco Invitrogen&#160;</td>
			<td>25030-024</td>
			<td></td>
		</tr>
		<tr>
			<td>Nestin, Mouse anti Nestin antibody</td>
			<td>Genetex</td>
			<td>GTX26142</td>
			<td>Use at 1:100, 4% PFA fixation, Triton X100 at 0.1%</td>
		</tr>
		<tr>
			<td>Olig2, Rabbit anti Olig2 antibody</td>
			<td>Provided by Hirohide Takebayash</td>
			<td>Personal stock</td>
			<td>Use at 1:2000, 4% PFA fixation, Triton X100 at 0.1%</td>
		</tr>
		<tr>
			<td>Penicillin/Streptomycin/Fungizone</td>
			<td>Gibco Invitrogen&#160;</td>
			<td>15240-062</td>
			<td></td>
		</tr>
		<tr>
			<td>Podoplanin, Mouse anti Podoplanin antibody</td>
			<td>Acris</td>
			<td>DM3614P</td>
			<td>Use at 1:250, 4% PFA fixation, avoid Triton X100</td>
		</tr>
		<tr>
			<td>Poly-L-ornithine</td>
			<td>Sigma&#160;</td>
			<td>P3655</td>
			<td></td>
		</tr>
		<tr>
			<td>Putrescine</td>
			<td>Sigma&#160;</td>
			<td>P5780</td>
			<td>Skin and eye irritant. Appropriate protection required.</td>
		</tr>
		<tr>
			<td>Sodium selenite</td>
			<td>Sigma&#160;</td>
			<td>S5261</td>
			<td></td>
		</tr>
		<tr>
			<td>Sox10, Rabbit anti Sox10 antibody</td>
			<td>Millipore Chemicon</td>
			<td>AB5774</td>
			<td>Use at 1:200, 4% PFA fixation, Triton X100 at 0.1%</td>
		</tr>
		<tr>
			<td>TGFb1, rhTGFb1</td>
			<td>RnD Systems</td>
			<td>240-B-010</td>
			<td></td>
		</tr>
		<tr>
			<td>Uncoated Petri dishes</td>
			<td>Falcon Corning</td>
			<td>351029</td>
			<td></td>
		</tr>
	</tbody>
</table>

an enzyme- and serum-free neural stem cell culture model for emt investigation suited for drug discovery

Epithelial to mesenchymal transition (EMT) describes the process of epithelium transdifferentiating into mesenchyme. EMT is a fundamental process during embryonic development that also commonly occurs in glioblastoma, the most frequent malignant brain tumor. EMT has also been observed in multiple carcinomas outside the brain including breast cancer, lung cancer, colon cancer, gastric cancer. EMT is centrally linked to malignancy by promoting migration, invasion and metastasis formation. The mechanisms of EMT induction are not fully understood. Here we describe an in vitro system for standardized isolation of cortical neural stem cells (NSCs) and subsequent EMT-induction. This system provides the flexibility to use either single cells or explant culture. In this system, rat or mouse embryonic forebrain NSCs are cultured in a defined medium, devoid of serum and enzymes. The NSCs expressed Olig2 and Sox10, two transcription factors observed in oligodendrocyte precursor cells (OPCs). Using this system, interactions between FGF-, BMP- and TGF&#946;-signaling involving Zeb1, Zeb2, and Twist2 were observed where TGF&#946;-activation significantly enhanced cell migration, suggesting a synergistic BMP-/TGF&#946;-interaction. The results point to a network of FGF-, BMP- and TGF&#946;-signaling to be involved in EMT induction and maintenance. This model system is relevant to investigate EMT in vitro. It is cost-efficient and shows high reproducibility. It also allows for the comparison of different compounds with respect to their migration responses (quantitative distance measurement), and high-throughput screening of compounds to inhibit or enhance EMT (qualitative measurement). The model is therefore well suited to test drug libraries for substances affecting EMT.

This EMT model system is based on the standardized isolation of NSCs both as single cells or as explants from a specific region of the developing neural tube, the central cortex (Figures 1 and 2). For quantitative assessment, explants were seeded right at the center of a 500 &#181;m grid culture dish (Figure 3). Explants from the central cortex were first exposed to FGF2 for two days, followed by additional two days in different combinati...

Watch this Scientific Journal Video about An Enzyme- and Serum-free Neural Stem Cell Culture Model for EMT Investigation Suited for Drug Discovery at JoVE.com

An Enzyme- and Serum-free Neural Stem Cell Culture Model for EMT Investigation Suited for Drug Discovery

Epithelial to mesenchymal transition (EMT) allows cancers to become invasive. To investigate EMT, a neural stem cell (NSC)-based in vitro model devoid of serum and enzymes is described. This standardized system allows quantitative and qualitative assessment of cell migration, gene and protein expression. The model is suited for drug discovery.

Epithelial to mesenchymal transition (EMT) describes the process of epithelium transdifferentiating into mesenchyme. EMT is a fundamental process during ...

The overall goal of this procedure is to induce migration in typically non-migratory cells, to identify specific compounds that activate or block migration. This method can help to answer key questions in the field of cell migration and invasion, and may be of particular interest to scientists working with neural stem cells. The main advantage of this technique is that non-migratory and non-invasive cells can be analyzed during the process of becoming migratory and invasive.The implications of this technique extend toward the identification of novel compounds that block epithelial to mesenchymal transition, or EMT, which occurs in human high-grade gliomas believed to derive from neural stem cells. Though this method can provide insight into EMT and neural stem cells, it can also be used to study other epithelial cancers, such as breast, lung, or colon cancer. On embryonic day 14.5, confirm the correct age of the rat embryos by the presence of beginning digit formation in a rat forelimb.Next, transfer the embryos into individual, uncoated petri dishes filled with ice-cold PBS, which are placed under a stereo microscope. Use a pair of fine-tipped forceps to remove the embryonic hulls. Keep embryos in expansion medium on ice.Using two autoclave-sterilized fine forceps, and starting at the intersection of the developing telencephalon and diencephalon, pull simultaneously anteriorly and posteriorly, to remove the head skin and skull. Then, identify the midbrain-hindbrain boundary separating the mesencephalon from the rhombencephalon, and cut the rhombencephalon just at or below the midbrain-hindbrain boundary. Holding the block of the mesencephalon with a pair of forceps, sever the connection between the telencephalon and diencephalon at the skull base with the facial skeleton, and immerse the telencephalon, diencephalon, mesencephalon block in an uncoated petri dish of expansion medium on ice.When all of the neural blocks have been harvested in the same manner, transfer one telencephalon, diencephalon, mesencephalon block into fresh, ice-cold PBS under the microscope. To separate the mesencephalon from the diencephalon, first sever the tissue between the diencephalon and the telencephalon. Next, split the two telencephalic hemispheres, and identify the medial and lateral ganglionic eminences, which are visible through the future foramen interventriculare.Dissect along a straight line at the intersection between the medial and lateral ganglionic eminences and the anterior cortex, followed by a straight line through the cortex, hippocampus, and choroid plexus. Cut a second straight line through the cortex, hippocampus, and choroid plexus at the intersection of the caudal ganglionic eminence and the posterior cortex. Then, flatten out the telencephalon, identify the cortical hem containing the hippocampus and the choroid plexus.Separate the cortical hem from the cortex, leaving the size of the cortex identical to the size of the ganglionic eminences. Flip the cortex-ganglionic eminence block so that the ventricular side is touching the dish surface, and the meninges are facing up. Pinning the ganglionic eminences to the dish surface with one hand, use forceps in the other hand to peel off the meninges.Then, cut each cortex along the lateral ganglionic eminence, about half of the distance of the diameter of the lateral ganglionic eminence. To prepare the explant cultures, cut the cortices into explants of less than 400 microns in diameter, using a 400 micron grid below the dissection dish as a reference if necessary. Then, transfer all of the explants into a fresh petri dish with ice cold expansion medium.Next, remove the excess fibronectin from a previously-coated 35 millimeter tissue culture dish and allow the dish to dry. Then, place the fibronectin-coated dish over a 10 by 10 millimeter grid and add one milliliter of cold expansion medium to the center of the dish, allowing the medium to form a spherical drop. Place up to eight explants into the center of the drop with at least three millimeters of space between each piece of tissue.Then, carefully place the dish in a cell culture incubator without shaking to allow the explants to attach to the fibronectin-coated surface. After one hour, fill the dish to a final volume of two milliliters of expansion medium plus the growth factors or test substances of interest, and return the plate to the incubator. In this experiment, explants were seeded at the center of 500 micron-grid culture dishes and cultured in different growth factors.In the control and TGF Beta 1 alone treated explants, a strong proliferations, coupled with almost no migration was observed. BMP4 however, induced an intermediate cell migration and proliferation response. With the combination of BMP4 and TGF Beta 1 inducing the strongest migration and proliferation of all the groups.Once mastered, the neural stem cell can be isolated from 10 to 15 embryos in approximately two hours. While attempting this procedure, it is important to maintain all of the embryos and cell explants in ice-cold medium. This cost-efficient and highly-reproducible system provides the flexibility of using either single cells or explant cultures to study cell migration and invasion in vitro.Culturing the cells in large multi-well plates allows analysis of the effects of a variety of compounds on migration and invasion in parallel. Further, the system can be easily adapted for high throughput screening of novel compounds. After watching this video, you should have a good understanding of how to isolate neural stem cells with the potential to undergo EMT from the appropriate region of the developing cortex.

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Research

JoVE Journal

Developmental Biology

Neural Differentiation of Mouse Embryonic Stem Cells in Serum-free Monolayer Culture

The ability to differentiate mouse embryonic stem cells (ESC) to neural progenitors allows the study of the mechanisms controlling neural specification as well as the generation of mature neural cell types for further study. In this protocol we describe a method for the differentiation of ESC to neural progenitors using serum-free, monolayer culture. The method is scalable, efficient and results in production of ~70% neural progenitor cells within 4 - 6 days. It can be applied to ESC from various strains grown under a variety of conditions. Neural progenitors can be allowed to differentiate further into functional neurons and glia or analyzed by microscopy, flow cytometry or molecular techniques. The differentiation process is amenable to time-lapse microscopy and can be combined with the use of reporter lines to monitor the neural specification process. We provide detailed instructions on media preparation and cell density optimization to allow the process to be applied to most ESC lines and a variety of cell culture vessels.

This protocol describes in detail the method for generating neural progenitors from embryonic stem cells using a serum-free monolayer method. These progenitors can be used to derive mature neural cell types or to study the process of neural specification and is amenable to multiwell format scaling for compound screening.

The ability to differentiate mouse embryonic stem cells (ESC) to neural progenitors allows the study of the mechanisms controlling neural specification as ...

Culturing Human Pluripotent and Neural Stem Cells in an Enclosed Cell Culture System for Basic and Preclinical Research

This paper describes how to use a custom manufactured, commercially available enclosed cell culture system for basic and preclinical research. Biosafety cabinets (BSCs) and incubators have long been the standard for culturing and expanding cell lines for basic and preclinical research. However, as the focus of many stem cell laboratories shifts from basic research to clinical translation, additional requirements are needed of the cell culturing system. All processes must be well documented and have exceptional requirements for sterility and reproducibility. In traditional incubators, gas concentrations and temperatures widely fluctuate anytime the cells are removed for feeding, passaging, or other manipulations. Such interruptions contribute to an environment that is not the standard for cGMP and GLP guidelines. These interruptions must be minimized especially when cells are utilized for therapeutic purposes. The motivation to move from the standard BSC and incubator system to a closed system is that such interruptions can be made negligible. Closed systems provide a work space to feed and manipulate cell cultures and maintain them in a controlled environment where temperature and gas concentrations are consistent. This way, pluripotent and multipotent stem cells can be maintained at optimum health from the moment of their derivation all the way to their eventual use in therapy.

Here is a protocol to grow pluripotent stem cells (PSC) and neural stem cells (NSC) in an enclosed cell culture system that permits maximum sterility and reproducibility, replacing the traditional biosafety cabinet and incubator. This equipment meets clinical good manufacturing practice (cGMP) and clinical good lab practice (cGLP) guidelines.

This paper describes how to use a custom manufactured, commercially available enclosed cell culture system for basic and preclinical research. Biosafety ...

Prediction and Validation of Gene Regulatory Elements Activated During Retinoic Acid Induced Embryonic Stem Cell Differentiation

Embryonic development is a multistep process involving activation and repression of many genes. Enhancer elements in the genome are known to contribute to tissue and cell-type specific regulation of gene expression during the cellular differentiation. Thus, their identification and further investigation is important in order to understand how cell fate is determined. Integration of gene expression data (e.g., microarray or RNA-seq) and results of chromatin immunoprecipitation (ChIP)-based genome-wide studies (ChIP-seq) allows large-scale identification of these regulatory regions. However, functional validation of cell-type specific enhancers requires further in vitro and in vivo experimental procedures. Here we describe how active enhancers can be identified and validated experimentally. This protocol provides a step-by-step workflow that includes: 1) identification of regulatory regions by ChIP-seq data analysis, 2) cloning and experimental validation of putative regulatory potential of the identified genomic sequences in a reporter assay, and 3) determination of enhancer activity in vivo by measuring enhancer RNA transcript level. The presented protocol is detailed enough to help anyone to set up this workflow in the lab. Importantly, the protocol can be easily adapted to and used in any cellular model system.

In this work we provide an experimental workflow of how active enhancers can be identified and experimentally validated.

Embryonic development is a multistep process involving activation and repression of many genes. Enhancer elements in the genome are known to contribute to ...

Large-Scale Production of Cardiomyocytes from Human Pluripotent Stem Cells Using a Highly Reproducible Small Molecule-Based Differentiation Protocol

Maximizing the benefit of human pluripotent stem cells (hPSCs) for research, disease modeling, pharmaceutical and clinical applications requires robust methods for the large-scale production of functional cell types, including cardiomyocytes. Here we demonstrate that the temporal manipulation of WNT, TGF-&#946;, and SHH signaling pathways leads to highly efficient cardiomyocyte differentiation of single-cell passaged hPSC lines in both static suspension and stirred suspension bioreactor systems. Employing this strategy resulted in ~ 100% beating spheroids, consistently containing &#62; 80% cardiac troponin T-positive cells after 15 days of culture, validated in multiple hPSC lines. We also report on a variation of this protocol for use with cell lines not currently adapted to single-cell passaging, the success of which has been verified in 42 hPSC lines. Cardiomyocytes generated using these protocols express lineage-specific markers and show expected electrophysiological functionalities. Our protocol presents a simple, efficient and robust platform for the large-scale production of human cardiomyocytes.

Here, we present a robust, fast and scalable cardiomyocyte differentiation protocol for human pluripotent stem cells (hPSCs). Cardiomyocytes derived using this large-scale method can provide sufficient cell numbers for their effective use in human cardiovascular disease modeling, high-throughput drug screening, and potentially clinical applications.

Maximizing the benefit of human pluripotent stem cells (hPSCs) for research, disease modeling, pharmaceutical and clinical applications requires robust ...

Zika Virus Infection of Cultured Human Fetal Brain Neural Stem Cells for Immunocytochemical Analysis

Human fetal brain neural stem cells are a unique non-genetically modified model system to study the impact of various stimuli on human developmental neurobiology. Rather than use an animal model or genetically modified induced pluripotent cells, human neural stem cells provide an effective in vitro system to examine the effects of treatments, screen drugs, or examine individual differences. Here, we provide the detailed protocols for methods used to expand human fetal brain neural stem cells in culture with serum-free media, to differentiate them into various neuronal subtypes and astrocytes via different priming procedures, and to freeze and recover these cells. Furthermore, we describe a procedure of using human fetal brain neural stem cells to study Zika virus infection.

This article details the methods that are used to expand human fetal brain neural stem cells in culture, as well as how to differentiate them into various neuronal subtypes and astrocytes, with an emphasis on the use of neural stem cells to study Zika virus infection.

Human fetal brain neural stem cells are a unique non-genetically modified model system to study the impact of various stimuli on human developmental ...

Using Human Induced Pluripotent Stem Cell-derived Hepatocyte-like Cells for Drug Discovery

The ability to differentiate human induced pluripotent stem cells (iPSCs) into hepatocyte-like cells (HLCs) provides new opportunities to study inborn errors in hepatic metabolism. However, to provide a platform that supports the identification of small molecules that can potentially be used to treat liver disease, the procedure requires a culture format that is compatible with screening thousands of compounds. Here, we describe a protocol using completely defined culture conditions, which allow the reproducible differentiation of human iPSCs to hepatocyte-like cells in 96-well tissue culture plates. We also provide an example of using the platform to screen compounds for their ability to lower Apolipoprotein B (APOB) produced from iPSC-derived hepatocytes generated from a familial hypercholesterolemia patient. The availability of a platform that is compatible with drug discovery should allow researchers to identify novel therapeutics for diseases that affect the liver.

The protocol presented here describes a platform for identifying small molecules for the treatment of liver disease. A step-by-step description is presented detailing how to differentiate iPSCs into cells with hepatocyte characteristics in 96-well plates, and to use the cells to screen for small molecules with potential therapeutic activity.

The ability to differentiate human induced pluripotent stem cells (iPSCs) into hepatocyte-like cells (HLCs) provides new opportunities to study inborn ...

Live Cell Imaging of Chromosome Segregation During Mitosis

Chromosomes must be reliably and uniformly segregated into daughter cells during mitotic cell division. Fidelity of chromosomal segregation is controlled by multiple mechanisms that include the Spindle Assembly Checkpoint (SAC). The SAC is part of a complex feedback system that is responsible for prevention of a cell progress through mitosis unless all chromosomal kinetochores have attached to spindle microtubules. Chromosomal lagging and abnormal chromosome segregation is an indicator of dysfunctional cell cycle control checkpoints and can be used to measure the genomic stability of dividing cells. Deregulation of the SAC can result in the transformation of a normal cell into a malignant cell through the accumulation of errors during chromosomal segregation. Implementation of the SAC and the formation of the kinetochore complex are tightly regulated by interactions between kinases and phosphatase such as Protein Phosphatase 2A (PP2A). This protocol describes live cell imaging of lagging chromosomes in mouse embryonic fibroblasts isolated from mice that had a knockout of the PP2A-B56&#947; regulatory subunit. This method overcomes the shortcomings of other cell cycle control imaging techniques such as flow cytometry or immunocytochemistry that only provide a snapshot of a cell cytokinesis status, instead of a dynamic spatiotemporal visualization of chromosomes during mitosis.

This protocol describes an easy and convenient method to label and visualize live chromosomes in mitotic cells using Histone2B-GFP BacMam 2.0 label and a spinning disc confocal microscopy system.

Chromosomes must be reliably and uniformly segregated into daughter cells during mitotic cell division. Fidelity of chromosomal segregation is controlled ...

Real-time Live-cell Flow Cytometry to Investigate Calcium Influx, Pore Formation, and Phagocytosis by P2X7 Receptors in Adult Neural Progenitor Cells

Live-cell flow cytometry is increasingly used among cell biologists to quantify biological processes in a living cell culture. This protocol describes a method whereby live-cell flow cytometry is extended upon to analyze the multiple functions of P2X7 receptor activation in real-time. Using a time module installed on a flow cytometer, live-cell functionality can be assessed and plotted over a given time period to explore the kinetics of calcium influx, transmembrane pore formation, and phagocytosis. This simple method is advantageous as all three canonical functions of the P2X7 receptor can be assessed using one machine, and the gathered data plotted over time provides information on the entire live-cell population rather than single-cell recordings often obtained using technically challenging patch-clamp methods. Calcium influx experiments use a calcium indicator dye, while P2X7 pore formation assays rely on ethidium bromide being allowed to pass through the transmembrane pore formed upon high agonist concentrations. Yellow-green (YG) latex beads are utilized to measure phagocytosis. Specific agonists and antagonists are applied to investigate the effects of P2X7 receptor activity. Individually, these methods can be modified to provide quantitative data on any number of calcium channels and purinergic and scavenger receptors. Taken together, they highlight how the use of real-time live-cell flow cytometry is a rapid, cost-effective, reproducible, and quantifiable method to investigate P2X7 receptor function.

Providing single-cell sensitivity, real-time flow cytometry is uniquely suited to quantify multimodal receptor functions of live cultures. Using adult neural progenitor cells, the P2X7 receptor function was assessed via calcium influx detected by calcium indicator dye, transmembrane pore formation by ethidium bromide uptake, and phagocytosis using fluorescent latex beads.

Live-cell flow cytometry is increasingly used among cell biologists to quantify biological processes in a living cell culture. This protocol describes a ...

Controlled Cortical Impact Model of Mouse Brain Injury with Therapeutic Transplantation of Human Induced Pluripotent Stem Cell-Derived Neural Cells

Traumatic brain injury (TBI) is a leading cause of morbidity and mortality worldwide. Disease pathology due to TBI progresses from the primary mechanical insult to secondary injury processes, including apoptosis and inflammation. Animal modeling has been valuable in the search to unravel injury mechanisms and evaluate potential neuroprotective therapies. This protocol describes the controlled cortical impact (CCI) model of focal, open-head TBI. Specifically, parameters for producing a mild unilateral cortical injury are described. Behavioral consequences of CCI are analyzed using the adhesive tape removal test of bilateral sensorimotor integration. Regarding experimental therapy for TBI pathology, this protocol also illustrates a process for transplanting cultured cells into the brain. Neural cell cultures derived from human induced pluripotent stem cells (hiPSCs) were chosen for their potential to show superior functional restoration in human TBI patients. Chronic survival of hiPSCs in the host mouse brain tissue is detected using a modified DAB immunohistochemical process.

This protocol demonstrates methodologies for a mouse model of open-skull traumatic brain injury and transplantation of cultured human induced pluripotent stem cell-derived cells into the injury site. Behavioral and histologic tests of outcomes from these procedures are also described in brief.

Traumatic brain injury (TBI) is a leading cause of morbidity and mortality worldwide. Disease pathology due to TBI progresses from the primary mechanical ...

Generation of Induced Neural Stem Cells from Peripheral Mononuclear Cells and Differentiation Toward Dopaminergic Neuron Precursors for Transplantation Studies

Parkinson&#39;s disease (PD) is caused by degeneration of dopaminergic (DA) neurons at the substantia nigra pars compacta (SNpc) in the ventral mesencephalon (VM). Cell replacement therapy holds great promise for treatment of PD. Recently, induced neural stem cells (iNSCs) have emerged as a potential candidate for cell replacement therapy due to the reduced risk of tumor formation and the plasticity to give rise to region-specific neurons and glia. iNSCs can be reprogrammed from autologous somatic cellular sources, such as fibroblasts, peripheral blood mononuclear cells (PBMNCs) and various other types of cells. Compared with other types of somatic cells, PBMNCs are an appealing starter cell type because of the ease to access and expand in culture. Sendai virus (SeV), an RNA non-integrative virus, encoding reprogramming factors including human OCT3/4, SOX2, KLF4 and c-MYC, has a negative-sense, single-stranded, non-segmented genome that does not integrate into host genome, but only replicates in the cytoplasm of infected cells, offering an efficient and safe vehicle for reprogramming. In this study, we describe a protocol in which iNSCs are obtained by reprogramming PBMNCs, and differentiated into specialized VM DA neurons by a two-stage method. Then DA precursors are transplanted into unilaterally 6-hyroxydopamine (6-OHDA)-lesioned PD mouse models to evaluate the safety and efficacy for treatment of PD. This method provides a platform to investigate the functions and therapeutic effects of patient-specific DA neural cells in vitro and in vivo.

The protocol presents the reprogramming of peripheral blood mononuclear cells to induce neural stem cells by Sendai virus infection, differentiation of iNSCs into dopaminergic neurons, transplantation of DA precursors into the unilaterally-lesioned Parkinson&#39;s disease mouse models, and evaluation of the safety and efficacy of iNSC-derived DA precursors for PD treatment.