Name: preparation of primary mixed glial cultures from adult mouse spinal cord tissue
Uploaded: 2016-11-19T14:00:00
Description: Watch this Scientific Journal Video about Preparation of Primary Mixed Glial Cultures from Adult Mouse Spinal Cord Tissue at JoVE.com

Adult spinal cord mixed cultures were first developed using rats with grant support from an NIH/NIDA R01 award (PI De Leo) and an NIH T32 training grant (PI Green). These methods were further adapted for mouse spinal cords with support from the following grants: NIH/NIDA 5K01DA023503 (PI Cao), NIH/NINDS 5R21NS066130 (PI Cao), and NIH/NIGMS P20GM103643 (PI Meng). The authors would also like to thank Dr. Alejandro M. S. Mayer, Department of Pharmacology, Chicago College of Osteopathic Medicine, for his technical help in obtaining microglia-rich mixed glial cells.

The following protocol was approved by the Institutional Animal Care and Use Committee (IACUC) at the University of New England. The following protocol is for preparing glial cultures from 4 adult mouse spinal cords.
1. Preparation of Solutions in a Culture Hood under Aseptic Conditions
<ol>
	<li>Prepare culture media: complete Dulbecco&#39;s modification of Eagle&#39;s media (cDMEM) containing DMEM (with 4.5 g/L glucose), 10% Fetal Bovine Serum (FBS), 2 mM L-glutamine, 100 IU/mL penicillin,...

<ol>
	<li>Gaskin, D. J., Richard, P. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=The+economic+costs+of+pain+in+the+United+States.">The economic costs of pain in the United States.</a> J Pain. 13 (8), 715-724 (2012).</li><li>Ji, R. R., Berta, T., Nedergaard, M. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Glia+and+pain:+Is+chronic+pain+a+gliopathy?.">Glia and pain: Is chronic pain a gliopathy?.</a> Pain. 154 (01), S10-S28 (2013).</li><li>Ni, M., Aschner, M., Maines, M. 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T., Maddula, S., Bell, H., Cao, L. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Involvement+of+calcitonin+gene-related+peptide+and+CCL2+production+in+CD40-mediated+behavioral+hypersensitivity+in+a+model+of+neuropathic+pain.">Involvement of calcitonin gene-related peptide and CCL2 production in CD40-mediated behavioral hypersensitivity in a model of neuropathic pain.</a> Neuron Glia Biol. 7 (2-4), 117-128 (2011).</li><li>Blasi, E., Barluzzi, R., Bocchini, V., Mazzolla, R., Bistoni, F. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Immortalization+of+murine+microglial+cells+by+a+v-raf+/+v-myc+carrying+retrovirus.">Immortalization of murine microglial cells by a v-raf / v-myc carrying retrovirus.</a> J Neuroimmunol. 27 (2), 229-237 (1990).</li><li>Bocchini, V., et al. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=An+immortalized+cell+line+expresses+properties+of+activated+microglial+cells.">An immortalized cell line expresses properties of activated microglial cells.</a> J Neurosci Res. 31 (4), 616-621 (1992).</li><li>Alliot, F. O., Marty, M. C., Cambier, D., Pessac, B. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=A+spontaneously+immortalized+mouse+microglial+cell+line+expressing+CD4.">A spontaneously immortalized mouse microglial cell line expressing CD4.</a> Dev Brain Res. 95 (1), 140-143 (1996).</li><li>Alliot, F. O., Pessac, B. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Astrocytic+cell+clones+derived+from+established+cultures+of+8-day+postnatal+mouse+cerebella.">Astrocytic cell clones derived from established cultures of 8-day postnatal mouse cerebella.</a> Brain Res. 306 (1-2), 283-291 (1984).</li><li>Malon, J. T., et al. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Microglial+content-dependent+inhibitory+effects+of+calcitonin+gene-related+peptide+(CGRP)+on+murine+retroviral+infection+of+glial+cells.">Microglial content-dependent inhibitory effects of calcitonin gene-related peptide (CGRP) on murine retroviral infection of glial cells.</a> J Neuroimmunol. 279, 64-70 (2015).</li><li>Cao, L., DeLeo, J. A. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=CNS+Infiltrating+CD4(+)+T+lymphocytes+Contribute+to+Murine+Spinal+Nerve+Transection-Induced+Neuropathic+Pain.">CNS Infiltrating CD4(+) T lymphocytes Contribute to Murine Spinal Nerve Transection-Induced Neuropathic Pain.</a> Eur J Immunol. 38 (2), 448-458 (2008).</li><li>Mayer, A. 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It is critical to perform all steps-including the media changing schedule-in a consistent manner in order to obtain reproducible results between experiments. The following steps are particularly critical in obtaining excellent quality adult mixed glia.
The enzymatic digestion is an important aspect of this protocol. It is crucial that the tissue pieces are well-digested in order to obtain a single cell suspension. However, over-digestion will result in significantly fewer cells. Each lab needs...

Chronic pain is a serious health problem that affects approximately 100 million adults in the United States, with an estimated annual cost of up to $635 billion1. Mounting evidence has indicated a significant contribution of spinal cord glial cells in the development of neuropathic pain, one of the most devastating kinds of chronic pain2. A proper in vitro culture system would help significantly in further investigating the roles of glial cells at the cellular and molecular levels.
Currently, the in vitro glial culture systems utilized by researchers include mainly glial cells derived from cortical tissues of neonatal mouse or rat brains and immortalized glial cell lines derived from neonatal mouse or rat primary glial cells. Neonatal cells contain significant numbers of undifferentiated cells that can be further differentiated into glial cells (mainly astrocytes and microglia), thus providing abundant cells for experimental usage3. However, our previous study has shown that neonatal brain glial cells responded significantly differently from adult spinal cord glial cells upon lipopolysaccharide (LPS) stimulation. For example, interleukin (IL)-4 displayed enhanced inhibitory effects on LPS-induced nitric oxide (NO) production in adult rat spinal cord glia compared to neonatal brain glia4. Furthermore, the profiles of chemokine production upon stimulation by a neuropeptide, calcitonin gene-related peptide (CGRP), are unarguably different between neonatal mouse brain glia (methods described in Ref. 5) and adult mouse spinal cord glia (Figure 1). Established cell lines are easy to use and maintain and can provide a large number of cells in a short time period. In general, immortalized cell lines are generated either using a virus-mediated immortalization system (such as the widely-used microglial cell line BV2)6, 7 or following the identification of spontaneous transformation (such as the astrocyte cell line C8-D1A and microglial cell line C8-B4)8, 9. Cell lines are excellent in studying the molecular characteristics of astrocytes and microglia individually; however, the results obtained from cell lines always require further validation in primary cells or in&#160;in vivo conditions. It should also be noted that there has not been a report of a glial cell line that is derived from a rodent spinal cord glia.
To help&#160;investigating&#160;the role of spinal cord glial cells in the development of neuropathic pain, a culture system that is derived from the adult mouse spinal cord has been developed by adapting a previously-reported method used to generate adult rat mixed glial cultures4, 5. The mouse spinal cord glial culture was further refined recently10 and is described in more detail in this article. Adult spinal cord mixed glial cultures can be established with a mouse from selected strains that fit the needs of the particular study, and cells can be maintained in culture for up to 21 d post initiation of the culture. This method can be used in neuropathic pain studies, as well as in investigations of various neurological diseases that involve pathological changes within the spinal cord, such as amyotrophic lateral sclerosis (ALS), human immunodeficiency virus (HIV)-associated sensory neuropathy, and multiple sclerosis (MS).

<table border="0" cellpadding="0" cellspacing="0" width="2053">
	<tbody>
		<tr height="24">
			<td height="24" style="height:24px;width:489px;">Dulbecco&#8217;s modification of Eagle&#8217;s media (DMEM) with 4.5g/L glucose</td>
			<td style="width:277px;">Lonza</td>
			<td style="width:119px;">12-709F</td>
			<td style="width:1168px;">The cDMEM media is a standard, widely used culture media. Individual researcher can decide where to purchase the DMEM and all other component used to make cDMEM media.</td>
		</tr>
		<tr height="24">
			<td height="24" style="height:24px;">L-Glutamine (100x)</td>
			<td style="width:277px;">Lonza</td>
			<td style="width:119px;">17-605E</td>
			<td>The L-glutamine is a standard, widely used component for various culture media. Individual researcher can decide where to purchase L-glutamine.</td>
		</tr>
		<tr height="24">
			<td height="24" style="height:24px;width:489px;">Antibiotic-Antimycotic Solution (100x)</td>
			<td style="width:277px;">Corning-Mediatech</td>
			<td style="width:119px;">30-004-CI</td>
			<td>This is a combination of penicillin, streptomycin and Amphotericin formulated to contain 10,000 units/ml penicillin G, 10 mg/ml streptomycin sulfate and 25 &#181;g/ml amphotericin B. Individual researcher can decide where to purchase individual component.</td>
		</tr>
		<tr height="24">
			<td height="24" style="height:24px;">2-mercaptoethanol (2-ME)</td>
			<td style="width:277px;">Sigma-Aldrich</td>
			<td style="width:119px;">M3148</td>
			<td>A BioReagent, suitable for cell culture, molecular biology and electrophoresis.</td>
		</tr>
		<tr height="24">
			<td height="24" style="height:24px;">Papain dissociation system</td>
			<td style="width:277px;">Worthington Biochemical Corporation</td>
			<td>LK003150</td>
			<td>Individual components of this kit can be purchased separately.&#160;</td>
		</tr>
		<tr height="24">
			<td height="24" style="height:24px;width:489px;">Percoll</td>
			<td>GE Health Care</td>
			<td style="width:119px;">17-0891-01</td>
			<td>Percoll is sold as sterile solution. Undiluted Percoll can be re-autoclaved if needed.</td>
		</tr>
		<tr height="24">
			<td height="24" style="height:24px;width:489px;">Lab-line incubator/shaker&#160;</td>
			<td style="width:277px;">Barstead/Lab-line</td>
			<td style="width:119px;">MaxQ4000&#160;</td>
			<td>This is the incubator/shaker we have currently. Other types of shakers can be used instead.</td>
		</tr>
		<tr height="24">
			<td height="24" style="height:24px;width:489px;">Lipopolysaccharides, Salmonella Minnesota Re595&#160;</td>
			<td style="width:277px;">Sigma-Aldrich</td>
			<td style="width:119px;">L-9764</td>
			<td>Other strains of LPS can also induce glial responses. The magnitude of the responses may vary.</td>
		</tr>
		<tr height="21">
			<td height="21" style="height:21px;width:489px;">Mouse IL-6 DuoSet ELISA&#160;</td>
			<td style="width:277px;">R&#38;D Systems</td>
			<td style="width:119px;">DY406</td>
			<td>Each individual Researcher can select the ELISA kit he or she prefers.</td>
		</tr>
		<tr height="21">
			<td height="21" style="height:21px;width:489px;">Mouse TNF-alpha DuoSet ELISA</td>
			<td style="width:277px;">R&#38;D Systems</td>
			<td style="width:119px;">DY410</td>
			<td>Each individual Researcher can select the ELISA kit he or she prefers.</td>
		</tr>
		<tr height="21">
			<td height="21" style="height:21px;width:489px;">Mouse IP-10 (CXCL10) DuoSet ELISA</td>
			<td style="width:277px;">R&#38;D Systems</td>
			<td style="width:119px;">DY466</td>
			<td>Each individual Researcher can select the ELISA kit he or she prefers.</td>
		</tr>
		<tr height="21">
			<td height="21" style="height:21px;width:489px;">Mouse MCP-1 (CCL2) ELISA Opteia set</td>
			<td style="width:277px;">BD Biosciences</td>
			<td style="width:119px;">555260</td>
			<td>Each individual Researcher can select the ELISA kit he or she prefers.</td>
		</tr>
		<tr height="21">
			<td height="21" style="height:21px;width:489px;">Mouse chemokine Q-Plex</td>
			<td style="width:277px;">Quansys Biosciences</td>
			<td style="width:119px;">120251MS</td>
			<td>This product was available for in-house assay at the time. Instead, we sent out samples to the manufacturer for analysis.</td>
		</tr>
		<tr height="21">
			<td height="21" style="height:21px;width:489px;">APC-anti-mouse-CD45 (clone 30-F11)</td>
			<td style="width:277px;">eBioscience</td>
			<td style="width:119px;">17-0451</td>
			<td>Antibody of the same clone but from other vendors can be used.</td>
		</tr>
		<tr height="21">
			<td height="21" style="height:21px;width:489px;">FITC-anti-mouse-CD11b (clone M1/70)</td>
			<td style="width:277px;">eBioscience</td>
			<td style="width:119px;">11-0112</td>
			<td>Antibody of the same clone but from other vendors can be used.</td>
		</tr>
		<tr height="21">
			<td height="21" style="height:21px;width:489px;">Accuri C6 flow cytometer</td>
			<td style="width:277px;">BD Biosciences</td>
			<td style="width:119px;">BD Accuri C6&#160;</td>
			<td>Each individual Researcher can use any flow cytometer he or she prefers.</td>
		</tr>
		<tr height="21">
			<td height="21" style="height:21px;width:489px;">FlowJo software</td>
			<td style="width:277px;">Tree Star, Inc.</td>
			<td style="width:119px;">FlowJo7.6.5</td>
			<td>Each individual Researcher can use any analysis software he or she prefers.</td>
		</tr>
	</tbody>
</table>

preparation of primary mixed glial cultures from adult mouse spinal cord tissue

It has been well-accepted that spinal cord glial responses contribute significantly to the development of neuropathic pain. Tremendous information regarding glial activities at the cellular and molecular levels has been obtained through in vitro cell culture systems. The in vitro systems utilized, mainly include primary glia derived from neonatal brain cortical tissue and immortalized cell lines. However, these systems may not reflect the characteristics of spinal cord glial cells in vivo. In order to further investigate the roles of spinal cord glial cells in the development of peripheral nerve injury-induced neuropathic pain using a culture system that better reflects the in vivo condition, our laboratory has developed a method to establish primary spinal cord mixed glial cultures from adult mice. Briefly, spinal cords are collected from adult mice and processed through papain digestion followed by myelin removal with a density-gradient medium. Single cell suspensions are cultured in complete Dulbecco&#39;s modified Eagle media (cDMEM) supplemented with 2-mercaptoethanol (2-ME) at 35.9 oC. These culture conditions were optimized specifically for the growth of mixed glial cells. Under these conditions, cells are ready to be used for experimentation between 12 - 14 d&#160;(cells are usually in log phase during this time) after the establishment of the culture (D 0) and can be kept in culture conditions up to D 21. This culture system can be used to investigate the responses of spinal cord glial cells upon stimulation with various substances and agents. Besides neuropathic pain, this system can be used to study glial responses in other diseases that involve pathological changes of spinal cord glial cells.

This method can be used to prepare mixed glial cells from both mice and rats. The average total cell number per well in a 12-well plate on D 12 post-initiation of the culture should be relatively stable, with around 100,000 cells per well when cells are derived from mouse spinal cords. Glial cells obtained from this method can be used in experiments that are designed to examine adult spinal cord glial responses upon administration of substances and agents of interest. Figure 3&#16...

Watch this Scientific Journal Video about Preparation of Primary Mixed Glial Cultures from Adult Mouse Spinal Cord Tissue at JoVE.com

Preparation of Primary Mixed Glial Cultures from Adult Mouse Spinal Cord Tissue

The development of neuropathic pain involves pathological changes of spinal cord glial cells. A reliable glial culture system derived from adult spinal cord tissue and designed for studying these cells in vitro is lacking. Therefore, we show here how&#160;to establish primary mixed glial cultures from adult mouse spinal cord tissue.

It has been well-accepted that spinal cord glial responses contribute significantly to the development of neuropathic pain. Tremendous information ...

The overall goal of this protocol is to establish primary mixed glial cultures from adult mouse spinal cords for in vitro studies. This method provides us an in vitro system to investigate the roles of glial cells in neurological diseases that involve pathological changes within the spinal cord, such as neuropathic pain and multiple sclerosis. The main advantage of this technique is that the glial cultures are prepared from adult mouse spinal cord, providing a system that is more accurately reflecting the in vivo conditions.Demonstrating the procedure will be Jennifer Malon, a technician from my laboratory. Working in a tissue culture hood, transfer four mouse spinal cords into a petri dish of HBSS. Use sterile scissors and forceps to cut each of the spinal cords into small pieces.Then, transfer the pieces to a 50 millimeter conical tube containing Papain DNAse enzyme mixture. Avoid transferring HBSS to the enzyme mixture, as this may result in decreased performance of the enzyme. It is crucial that tissue pieces are well digested to obtain a single cell suspension.However, over digestion will result in fewer viable cells. Each lab needs to perform pilot tests to determine the exact digestion time based on what works best for their cells. Next, gently vortex the tube and then incubate at 37 degrees Celsius for one hour with orbital shaking at 150 rotations per minute.Following the incubation, vortex the tube, and then vigorously triturate the tissue using a five milliliter pipet to promote further dissociation. Then, transfer the cell suspension into a 15 milliliter tube and centrifuge for 300 x g for five minutes at room temperature. During the centrifugation, at 300 microliters of reconstituted albumin ovomucoid inhibitor solution to 2.7 milliliters of ABSS in a sterile tube and mix well.Then add 150 microliters of DNAse solution. Following the centifugation, remove the supernatant, and resuspend the cell pellet in the freshly prepared albumin ovomucoid inhibitor and DNAse solution. Vortex well to break the cell pellet.Then, add three milliliters of reconstituted albumin ovomucoid inhibitor solution, without DNAse, to the cell suspension. Centrifuge the cells at 70 x g for six minutes at room temperature. After the spin, remove the supernatant, which contains membrane fragments, and retain the pellet.To remove myelin from the dissociated spinal cord cells, first add eight milliliters of room temperature 20%gradient density medium into the tube containing the cell pellet and vortex gently. Next, centrifuge the cells at 800 x g for 30 minutes at room temperature without breaking. Following centrifugation, carefully aspirate the top layer of debris, which contains mostly myelin and the supernatant, leaving the pellet.To remove any remaining density gradient, wash the cells by resuspending the pellet with eight milliliters of cDMEM diluted with HBSS. Centrifuge the cells at 400g for 10 minutes at four degrees Celsius. Remove the supernatant, and wash the cells with diluted cDMEM as before.After removing the supernatant, the pellet can be stored on ice until seeding the cells. Once ready for plating, resuspend the cells in 14 milliliters of cDMEM, supplemented with 2-Mercaptoethanol. And add one milliliter of the cell suspension to each well in a 12 well plate.Plate extra wells that can be used to determine the average cell number per well and the microglial content of the culture. Once the cells have been plated, incubate the cells at 35.9 degrees Celsius with 5%carbon dioxide. Change the medium on day 1, which is the day after plating.Some cells are attached to the culture plate, but they are still mostly round. There are also many floating cells and significant debris. Repeat the media change three to four days thereafter until the cells are ready for treatment between days 12 and 14.Mixed glial cells from adult C57 black six mice were cultured at either 37 degrees Celsius or 35.9 degrees Celsius and analyzed via flow cytometry. As you can see, there is no obvious difference in the total cell populations at these temperatures. These representative plots show the CD45 positive CD11b positive microglia populations isolated from the total cell populations previously shown.This figure demonstrates that a higher microglial content can be obtained when mixed glia are cultured at 35.9 degrees Celsius, instead of 37 degrees Celsius. Adult spinal cord, mixed glial cultures were prepared from C67 black six mice. Representative images of the cultured cells at days one, four, eight, and 12 are shown.Images showing the typical progress of the culture, as well as demonstrating the importance of media, change at day one post-culture establishment. Once mastered, the initial set up of mixed glia cell culture can be completed in about four hours, if performed properly. Following the establishment of mixed glia culture, microglia depleted, and microglia enriched cultures, can be obtained from this initial mixed population.However, the yield of microglia enriched cells will be limited unless large number of spinal cords are used to establish cultures. This technique was initially designed to investigate the roles of glial cells during the development of neuropathic pain. However, it can be used to study other neurological diseases that involve pathological changes within the adult spinal cord.

preparation-primary-mixed-glial-cultures-from-adult-mouse-spinal-cord

Research

JoVE Journal

Neuroscience

The Preparation of Oblique Spinal Cord Slices for Ventral Root Stimulation

Electrophysiological recordings from spinal cord slices have proven to be a valuable technique to investigate a wide range of questions, from cellular to network properties. We show how to prepare viable oblique slices of the spinal cord of young mice (P2 - P11). In this preparation, the motoneurons retain&#160;their axons coming out from the ventral roots of the&#160;spinal cord. Stimulation of these axons elicits back-propagating action potentials invading the motoneuron&#160;somas and exciting the motoneuron&#160;collaterals within the spinal cord. Recording of antidromic action potentials is an immediate, definitive and elegant way to characterize motoneuron identity, which surpasses&#160;other identification methods. Furthermore, stimulating the motoneuron collaterals is a simple and reliable way to excite the collateral targets of the motoneurons within the spinal cord, such as other motoneurons or Renshaw cells. In this protocol, we present antidromic recordings from the motoneuron somas as well as Renshaw cell excitation, resulting from ventral root stimulation.

We show how to prepare oblique slices of the spinal cord in young mice. This preparation allows for the stimulation of the ventral roots.

Electrophysiological recordings from spinal cord slices have proven to be a valuable technique to investigate a wide range of questions, from cellular to ...

Zebrafish In Situ Spinal Cord Preparation for Electrophysiological Recordings from Spinal Sensory and Motor Neurons

Zebrafish, first introduced as a developmental model, have gained popularity in many other fields. The ease of rearing large numbers of rapidly developing organisms, combined with the embryonic optical clarity, served as initial compelling attributes of this model. Over the past two decades, the success of this model has been further propelled by its amenability to large-scale mutagenesis screens and by the ease of transgenesis. More recently, gene-editing approaches have extended the power of the model.
For neurodevelopmental studies, the zebrafish embryo and larva provide a model to which multiple methods can be applied. Here, we focus on methods that allow the study of an essential property of neurons, electrical excitability. Our preparation for the electrophysiological study of zebrafish spinal neurons involves the use of veterinarian suture glue to secure the preparation to a recording chamber. Alternative methods for recording from zebrafish embryos and larvae involve the attachment of the preparation to the chamber using a fine tungsten pin1,2,3,4,5. A tungsten pin is most often used to mount the preparation in a lateral orientation, although it has been used to mount larvae dorsal-side up4. The suture glue has been used to mount embryos and larvae in both orientations. Using the glue, a minimal dissection can be performed, allowing access to spinal neurons without the use of an enzymatic treatment, thereby avoiding any resultant damage. However, for larvae, it is necessary to apply a brief enzyme treatment to remove the muscle tissue surrounding the spinal cord. The methods described here have been used to study the intrinsic electrical properties of motor neurons, interneurons, and sensory neurons at several developmental stages6,7,8,9.

Zebrafish In Situ Spinal Cord Preparation for Electrophysiological Recordings from Spinal Sensory and Motor Neurons

This manuscript describes methods for electrophysiological recordings from spinal neurons of zebrafish embryos and larvae. The preparation maintains neurons in situ and often involves minimum dissection. These methods allow for the electrophysiological study of a variety of spinal neurons, from the initial electrical excitability acquisition through the early larval stages.

Zebrafish, first introduced as a developmental model, have gained popularity in many other fields. The ease of rearing large numbers of rapidly developing ...

Imaging Neural Activity in the Primary Somatosensory Cortex Using Thy1-GCaMP6s Transgenic Mice

The mammalian brain exhibits marked symmetry across the sagittal plane. However, detailed description of neural dynamics in symmetric brain regions in adult mammalian animals remains elusive. In this study, we describe an experimental procedure for measuring calcium dynamics through dual optical windows above bilateral primary somatosensory corticies (S1) in Thy1-GCaMP6s transgenic mice using 2-photon (2P) microscopy. This method enables recordings and quantifications of neural activity in bilateral mouse brain regions one at a time in the same experiment for a prolonged period in vivo. Key aspects of this method, which can be completed within an hour, include minimally invasive surgery procedures for creating dual optical windows, and the use of 2P imaging. Although we only demonstrate the technique in the S1 area, the method can be applied to other regions of the living brain facilitating the elucidation of structural and functional complexities of brain neural networks.

Imaging Neural Activity in the Primary Somatosensory Cortex Using Thy1-GCaMP6s Transgenic Mice

We describe an experimental procedure for measuring neuronal activity through dual optical windows above bilateral primary somatosensory corticies (S1) in Thy1-GCaMP6s transgenic mice using 2-photon (2P) microscopy in vivo.

The mammalian brain exhibits marked symmetry across the sagittal plane. However, detailed description of neural dynamics in symmetric brain regions in ...

Laminectomy and Spinal Cord Window Implantation in the Mouse

This protocol describes a method for spinal cord laminectomy and glass window implantation for in vivo imaging of the mouse spinal cord. An integrated digital vaporizer is utilized to achieve a stable plane of anesthesia at a low-flow rate of isoflurane. A single vertebral spine is removed, and a commercially available cover-glass is overlaid on a thin agarose bed. A 3D-printed plastic backplate is then affixed to the adjacent vertebral spines using tissue adhesive and dental cement. A stabilization platform is used to reduce motion artifact from respiration and heartbeat. This rapid and clamp-free method is well-suited for acute multi-photon fluorescence microscopy. Representative data are included for an application of this technique to two-photon microscopy of the spinal cord vasculature in transgenic mice expressing eGFP:Claudin-5 &#8212; a tight junction protein.

This protocol describes implantation of a glass window onto the spinal cord of a mouse to facilitate visualization by intravital microscopy.

This protocol describes a method for spinal cord laminectomy and glass window implantation for in vivo imaging of the mouse spinal cord. An integrated ...

Isolation of Adult Spinal Cord Nuclei for Massively Parallel Single-nucleus RNA Sequencing

Probing an individual cell&#39;s gene expression enables the identification of cell type and cell state. Single-cell RNA sequencing has emerged as a powerful tool for studying transcriptional profiles of cells, particularly in heterogeneous tissues such as the central nervous system. However, dissociation methods required for single cell sequencing can lead to experimental changes in the gene expression and cell death. Furthermore, these methods are generally restricted to fresh tissue, thus limiting studies on archival and bio-bank material. Single nucleus RNA sequencing (snRNA-Seq) is an appealing alternative for transcriptional studies, given that it accurately identifies cell types, permits the study of tissue that is frozen or difficult to dissociate, and reduces dissociation-induced transcription. Here, we present a high-throughput protocol for rapid isolation of nuclei for downstream snRNA-Seq. This method enables isolation of nuclei from fresh or frozen spinal cord samples and can be combined with two massively parallel droplet encapsulation platforms.

Here, we present a protocol to rapidly isolate high-quality nuclei from the fresh or frozen tissue for downstream massively parallel RNA sequencing. We include detergent-mechanical and hypotonic-mechanical tissue disruption and cell lysis options, both of which can be used for isolation of nuclei.

Probing an individual cell&#39;s gene expression enables the identification of cell type and cell state. Single-cell RNA sequencing has emerged as a ...

Intra-Arterial Delivery of Neural Stem Cells to the Rat and Mouse Brain: Application to Cerebral Ischemia

Neural stem cell (NSC) therapy is an emerging innovative treatment for stroke, traumatic brain injury and neurodegenerative disorders. As compared to intracranial delivery, intra-arterial administration of NSCs is less invasive and produces a more diffuse distribution of NSCs within the brain parenchyma. Further, intra-arterial delivery allows the first-pass effect in the brain circulation, lessening the potential for trapping of cells in peripheral organs, such as liver and spleen, a complication associated with peripheral injections. Here, we detail the methodology, in both mice and rats, for delivery of NSCs through the common carotid artery (mouse) or external carotid artery (rat) to the ipsilateral hemisphere after an ischemic stroke. Using GFP-labeled NSCs, we illustrate the widespread distribution achieved throughout the rodent ipsilateral hemisphere at 1 d, 1 week and 4 weeks after postischemic delivery, with a higher density in or near the ischemic injury site. In addition to long-term survival, we show evidence of differentiation of GFP-labeled cells at 4 weeks. The intra-arterial delivery approach described here for NSCs can also be used for administration of therapeutic compounds, and thus has broad applicability to varied CNS injury and disease models across multiple species.

A method for delivering neural stem cells, adaptable for injecting solutions or suspensions, through the common carotid artery (mouse) or external carotid artery (rat) after ischemic stroke is reported. Injected cells are distributed broadly throughout the brain parenchyma and can be detected up to 30 d after delivery.

Neural stem cell (NSC) therapy is an emerging innovative treatment for stroke, traumatic brain injury and neurodegenerative disorders. As compared to ...

Magnetic Isolation of Microglial Cells from Neonate Mouse for Primary Cell Cultures

Microglia, as brain resident macrophages, are fundamental to several functions, including response to environmental stress and brain homeostasis. Microglia can adopt a large spectrum of activation phenotypes. Moreover, microglia that endorse pro-inflammatory phenotype is associated with both neurodevelopmental and neurodegenerative disorders. In vitro studies are widely used in research to evaluate potential therapeutic strategies in specific cell types. In this context studying microglial activation and neuroinflammation in vitro using primary microglial cultures is more relevant than microglial cell lines or stem-cell-derived microglia. However, the use of some primary cultures might suffer from a lack of reproducibility. This protocol proposes a reproducible and relevant method of magnetically isolating microglia from neonate pups. Microglial activation using several stimuli after 4 h and 24 h by mRNA expression quantification and a Cy3-bead phagocytic assay is demonstrated here. The current work is expected to provide an easily reproducible technique for isolating physiologically relevant microglia from juvenile developmental stages.

Primary microglia cultures are commonly used to evaluate new anti-inflammatory molecules. The present protocol describes a reproducible and relevant method to magnetically isolate microglia from neonate pups.

Microglia, as brain resident macrophages, are fundamental to several functions, including response to environmental stress and brain homeostasis. ...

Embryonic Mouse Brain Mixed Cell Cultures to Study Infection and Innate Immunity

Establishing Mixed Neuronal and Glial Cell Cultures from Embryonic Mouse Brains to Study Infection and Innate Immunity

Models of the central nervous system (CNS) must recapitulate the complex network of interconnected cells found in vivo. The CNS consists primarily of neurons, astrocytes, oligodendrocytes, and microglia. Due to increasing efforts to replace and reduce animal use, a variety of in vitro cell culture systems have been developed to explore innate cell properties, which allow the development of therapeutics for CNS infections and pathologies. Whilst certain research questions can be addressed by human-based cell culture systems, such as (induced) pluripotent stem cells, working with human cells has its own limitations with regard to availability, costs, and ethics. Here, we describe a unique protocol for isolating and culturing cells from embryonic mouse brains. The resulting mixed neural cell cultures mimic several cell populations and interactions found in the brain in vivo. Compared to current equivalent methods, this protocol more closely mimics the characteristics of the brain and also garners more cells, thus allowing for more experimental conditions to be investigated from one pregnant mouse. Further, the protocol is relatively easy and highly reproducible. These cultures have been optimized for use at various scales, including 96-well based high throughput screens, 24-well microscopy analysis, and 6-well cultures for flow cytometry and reverse transcription-quantitative polymerase chain reaction (RT-qPCR) analysis. This culture method is a powerful tool to investigate infection and immunity within the context of some of the complexity of the CNS with the convenience of in vitro methods.

Author Spotlight: Establishing Mixed Neuronal and Glial Cell Cultures from Embryonic Mouse Brains to Study Infection and Innate Immunity  

This protocol presents a unique way of generating central nervous system cell cultures from embryonic day 17 mouse brains for neuro(immuno)logy research. This model can be analyzed using various experimental techniques, including RT-qPCR, microscopy, ELISA, and flow cytometry.

Models of the central nervous system (CNS) must recapitulate the complex network of interconnected cells found in vivo. The CNS consists primarily of ...

Extraction and Enzymatic Purification of Microglia from the Mouse Spinal Cord

Rapid and Efficient Enrichment of Mouse Spinal Cord Microglia

The vertebral column defines a vertebrate and shapes the spinal canal, a cavity that encloses and safeguards the spinal cord. Proper development and function of the mammalian central nervous system rely significantly on the activity of resident macrophages known as microglia. Microglia display heterogeneity and multifunctionality, enabling distinct gene expression and behavior within the spinal cord and brain. Numerous studies have explored cerebral microglia function, detailing purification methods extensively. However, the purification of microglia from the spinal cord in mice lacks a comprehensive description. In contrast, the utilization of a highly purified collagenase, as opposed to an unrefined extract, lacks reporting within central nervous system tissues. In this study, the vertebral column and spinal cord were excised from 8-10 week-old C57BL/6 mice. Subsequent digestion employed a highly purified collagenase, and microglia purification utilized a density gradient. Cells underwent staining for flow cytometry, assessing viability and purity through CD11b and CD45 staining. Results yielded an average viability of 80% and a mean purity of 95%. In conclusion, manipulation of mouse microglia involved digestion with a highly purified collagenase, followed by a density gradient. This approach effectively produced substantial spinal cord microglia populations.

Author Spotlight: Microglia Research on Spinal Cord Heterogeneity and Purification 

Microglia are regarded as some of the most versatile cells in the body, capable of morphological and functional adaptation. Their heterogeneity and multifunctionality enable the maintenance of brain homeostasis, while also being linked to various neurological pathologies. Here, a technique for purifying spinal cord microglia is described.

The vertebral column defines a vertebrate and shapes the spinal canal, a cavity that encloses and safeguards the spinal cord. Proper development and ...

Efficient Extraction of Astrocytes and Microglia from the Adult Mouse Spinal Cord

Isolation of Pure Astrocytes and Microglia from the Adult Mouse Spinal Cord For In Vitro Assays and Transcriptomic Studies

Astrocytes and microglia play pivotal roles in central nervous system development, injury responses, and neurodegenerative diseases. These highly dynamic cells exhibit rapid responses to environmental changes and display significant heterogeneity in terms of morphology, transcriptional profiles, and functions. While our understanding of the functions of glial cells in health and disease has advanced substantially, there remains a need for in vitro, cell-specific analyses conducted in the context of insults or injuries to comprehensively characterize distinct cell populations. Isolating cells from the adult mouse offers several advantages over cell lines or neonatal animals, as it allows for the analysis of cells under pathological conditions and at specific time points. Furthermore, focusing on spinal cord-specific isolation, excluding brain involvement, enables research into spinal cord pathologies, including experimental autoimmune encephalomyelitis, spinal cord injury, and amyotrophic lateral sclerosis. This protocol presents an efficient method for isolating astrocytes and microglia from the adult mouse spinal cord, facilitating immediate or future analysis with potential applications in functional, molecular, or proteomic downstream studies.

Author Spotlight: Isolation of Glial Cells from the Adult Mouse Spinal Cord 

This protocol outlines the isolation of purified astrocytes and microglia from the adult mouse spinal cord, facilitating subsequent applications such as RNA analysis and cell culture. It includes detailed cell dissociation methods and procedures designed to enhance both the quality and yield of isolated cells.

Astrocytes and microglia play pivotal roles in central nervous system development, injury responses, and neurodegenerative diseases. These highly dynamic ...