This work was performed using the Division of Brain Sciences, Department of Medicine, Imperial College London startup funds to K.N.A.

NOTE: The animals were maintained and handled in compliance with the institutional guidelines and all animal procedures were approved by the Imperial College&#39;s Animal Welfare and Ethical Review Body (AWERB) and the Home Office and Harvard University Institutional Animal Care and Use Committee (IACUC), in compliance with federal and state regulations.
1. Reagent and Equipment Setup
<ol>
	<li>Thaw, aliquot and store 1 mg/ml&#160;Laminin solution at &#8211;80 &#186;C. Dissolve 2 &#181;l in 1 ml DMEM/F12, resulting in a coating concentration of 1-2 &#181;g/cm2. 
	NOTE: Thaw Laminin slowly on ice and dissolve in cold DMEM/F12 and immediately add it to the plates/coverslips.</li>
	<li>Dilute 75 ml of 0.01% Poly-L-ornithine in 425 ml PBS and store at 4 &#186;C. 
	NOTE: The shelf life of the working solution is up to one month.</li>
	<li>Dissolve 25% (wt/vol) BSA in PBS, pH 7.4, and store at 4 &#186;C for up to a year.</li>
	<li>Prepare 50% FBS (in HBSS) deactivation media.</li>
	<li>Prepare complete medium by adding 50 U/ml penicillin and streptomycin, 1x N2 supplement, 5% (vol/vol) FBS, 0.36% D-(+)-Glucose (wt/vol), 0.25% BSA (wt/vol) to DMEM/F12 and store at 4 &#186;C. 
	NOTE: The shelf life is up to 10 days.</li>
	<li>Place coverslips in boiling 70% (vol/vol) ethanol for at least 30 min to remove any traces of grease and autoclave.</li>
	<li>Place coverslips in 24-well plates and add 500 &#181;l Poly-L-ornithine solution to each well. Incubate 1 hr under the tissue culture hood at RT and then, wash 3 times with 500 &#181;l water. Add 500 &#181;l laminin solution to each plate and incubate O/N in the humidified tissue culture incubator at 37 &#186;C. 
	NOTE: While no washes are necessary after laminin treatment, washing the poly-L-ornithine less than three times results in death of the cells 24 h after culturing.</li>
	<li>Polish the tips of glass pipettes over natural gas or torch flame. 
	NOTE: After this step the diameter of the tip should be about half of its normal size.</li>
	<li>Cut the caps of 1.5 ml microcentrifuge tubes, using an autoclaved scissor and autoclave.</li>
</ol>
2. Dissection of Embryonic Ventral Midbrain
<ol>
	<li>Narcotize timed-pregnant (E12.5) dams by CO2 inhalation and then euthanize by cervical dislocation.</li>
	<li>Spray the abdomen with 70% ethanol and make an abdominal incision until the uterine sacs are all exposed. Using forceps cut the vaginal attachment and remove uterus. Place the uterus in ice-cold HBSS, in a 100 mm Petri dish.</li>
	<li>Remove embryos from the uterus and amniotic sac, using forceps (Figure&#160;1C). Place embryos in fresh ice-cold HBSS. 
	NOTE: The rectangle in Figure 1D indicates the location of embryonic ventral midbrain.</li>
	<li>Place the embryos under a dissection microscope (10x magnification) and dissect the mesencephalic arch by cutting the brain at the isthmus and mesencephalic-diencephalic boundary region, using the bioscissor and forceps (Figure 1E, please refer to Figure 1A for lines of incision).</li>
	<li>After taking out the entire midbrain, make a cut in the mediodorsal midbrain (Figure 1F).</li>
	<li>Remove meninges, using two forceps (Figure 1H). 
	NOTE: CRITICAL STEP: This step is essential for optimal neuronal yield and survival. Since the culture conditions are optimal for brain cells, most of the cells from the surrounding tissue die after plating and the apoptotic signal from this tissue may damage integrity of the cultures.</li>
	<li>Flatten the midbrain tissue on the Petri dish to observe the butterfly shape and cut approximately half of each wing, using a sterilized shaving blade (Figure 1H,I). 
	NOTE: Figure 1J depicts the isolated ventral midbrain.</li>
	<li>Transfer the piece of ventral midbrain into ice-cold HBSS in a 15 ml conical tube and proceed with the next embryo. 
	NOTE: Steps 2.1-2.8 should not take more than 1 hr. Keeping the embryos beyond this time frame on ice decreases cell viability significantly.</li>
</ol>
3. Dissociation of Ventral Midbrain Cells
<ol>
	<li>Transfer the pieces of ventral midbrain under a laminar flow hood. Remove the HBSS and add 1 ml pre-warmed (37 &#186;C) 0.05% trypsin-EDTA into the conical tube (volumes enough for up to 12 pieces of ventral midbrain). Incubate the tissue at 37 &#186;C for 5-10 min.</li>
	<li>Remove trypsin-EDTA under the hood and add 1 ml de-activation medium (the serum will deactivate trypsin) to the tissue.</li>
	<li>Remove the deactivation medium and wash the tissue in 1 ml complete medium twice. 
	NOTE: Avoid removing all the medium from the tube and pipetting the tissue, to prevent discarding the dissociated cells.</li>
	<li>Add 1ml complete medium and triturate the tissue with a fire-polished glass pipette. Avoid formation of bubbles and continue triturating until single cell suspension is achieved. 
	NOTE: Usually, 8-10 passes through the restricted tip are required for complete dissociation.</li>
	<li>Centrifuge the cells at 400 x g for 5 min at RT and remove the medium.</li>
	<li>Re-suspend the pellet in 1 ml complete medium by slowly pipetting up and down for up to four times.</li>
</ol>
4. Plating Ventral Midbrain Cells
<ol>
	<li>Mix 10 &#181;l of the cell suspension with 90 &#181;l Trypan blue solution and count the number of cells with a hemocytometer. 
	NOTE: Viability of the cells can also be checked at this stage.</li>
	<li>Place sterilized microcentrifuge tube caps in 100 mm Petri dishes and transfer the Poly-L-ornithine/Laminin coated coverslips, using forceps, one at a time on top of the caps. 
	NOTE: Do not wash the coverslips and avoid drying the laminin, since this may cause uneven cultures and decrease in survivability of the cells.</li>
	<li>Adjust the volume to 1,500 cells per 1 &#181;l by adding complete medium and add 100 &#181;l (total of 150,000 cells) of the cell suspension on top of each coverslip (the volume is optimal to cover the surface of the coverslip without spillage). Close the Petri dishes and incubate them for 1 hr in a humidified tissue culture incubator (37 &#176;C, 5% CO2). 
	NOTE: CRITICAL STEP: This step is required for enhancing the attachment and viability of the cells and for increasing the number of coverslips per embryo. Alternatively, the cells can be transferred directly into the wells (containing coverslips) but the number of cells should be increased to 350,000 per well (instead of 150,000). In other words, using this method, 8-10 coverslips can be acquired, while direct transfer yields about 3-4 coverslips because of the cells, which attach to the plates (beside or underneath the coverslips). The average viability of the cultures, using this method was around 90%.</li>
</ol>
5. Culture Growth and Maintenance
<ol>
	<li>After 1 hr of incubation, carefully transfer the coverslips including the medium into 24-well plates, containing 400 &#181;l pre-warmed (to 37 &#186;C) complete medium (total volume: 500 &#181;l). Incubate the cells O/N at 37 &#186;C.</li>
	<li>Within 24 hr after incubation of the wells, gently add 500 &#181;l complete medium into each well. 
	NOTE: The first few hours is the most critical stage for survival of the dopaminergic neurons and the number of surviving cells does not change significantly beyond this point.</li>
	<li>Do not add additional media to the cultures for the first two weeks or until the medium becomes yellow. If culturing for more than two weeks or medium color changes to yellow, exchange half of the media (500 &#181;l) with fresh complete pre-warmed media (typically every two weeks). 
	NOTE: Dopaminergic neurons within the cultures would survive for more than 6 weeks under these conditions.</li>
</ol>

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H., Heller, A. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Specific+modulation+of+dopamine+expression+in+neuronal+hybrid+cells+by+primary+cells+from+different+brain+regions.">Specific modulation of dopamine expression in neuronal hybrid cells by primary cells from different brain regions.</a> Proc Natl Acad Sci U S A. 89, 8943-8947 (1992).</li><li>Alavian, K. N., Sgado, P., Alberi, L., Subramaniam, S., Simon, H. H. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Elevated+P75NTR+expression+causes+death+of+engrailed-deficient+midbrain+dopaminergic+neurons+by+Erk1/2+suppression.">Elevated P75NTR expression causes death of engrailed-deficient midbrain dopaminergic neurons by Erk1/2 suppression.</a> Neural Dev. 4, 11 (2009).</li><li>Chung, C. 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No conflict of interest declared.

Dopaminergic neurons in midbrain are the main source of dopamine in the central nervous system. They are divided into three groups, substantia nigra pars compacta (SNpc), ventral tegmental area (VTA) and retrorubral field (RRF) 10,11. The neurons in SNpc and VTA give rise to major dopaminergic pathways, mesocortical, mesolimbic and nigro-striatal, involved in functions such as control of emotion, motivation and motor behavior. Demise of the neurons in SNpc and functional disruption of the nigrostria...

Loss of dopaminergic neurons from the substantia nigra pars compacta leads to the cardinal motor symptoms of Parkinson&#8217;s Disease (PD), the second most prevalent neurodegenerative disorder. The underlying cause of the demise of this mesencephalic neuronal population is not known. To study the biochemical pathways responsible for the development and modulating neurophysiological properties and survival of mesDA neurons, several cell culture and animal model systems have been used. Immortalized cell lines, including the rat dopaminergic cell line 1RB3AN27(N27), the human dopaminergic neuroblastoma cell line SH-SY5Y, the mouse dopaminergic hybrid cell line MN9D and human mesencephalic LUHMES cells have been used for biochemical and limited mechanistic studies 1-5. For the study of the specific loss of mesDA neurons, several neurotoxin-based and genetic models have been developed 6-8. Primary ventral midbrain cultures, provide an indispensable tool for studying the neuronal and synaptic properties of the dopaminergic neurons and the pathways involved in pathogenesis of this common disorder.
Here we present a detailed protocol for the isolation of mesencephalic dopaminergic neurons, which contains modifications resulting in higher survivability and increased yield of coverslips per embryo. Use of pre-mature E12.5 mouse mesencephalon (E14.5 in rat) enhances survivability. At this age neurons have not developed axons yet, which leaves cells intact during dissection and minimizes the stress thereby significantly increasing viability. In addition, careful dissection of the ventral midbrain, as described in section 2 of this protocol, further enhances survivability. To increase the numbers of coverslips per embryo, an alternative plating method is presented in section 4 of this protocol. This leads to a yield of up to 10 coverslips per embryo as compared to 4 coverslips under standard plating conditions thus reducing the amount of animals per experiment.
Neurons in culture exhibit outgrowth of axons and dentrites, form synaptic connections and reveal the presence of neuronal and synaptic markers making these cultures suitable for live cell imaging, immunocytochemical and electrophysiological studies. Furthermore, the use of neuronal cultures facilitates genetic and pharmacologic manipulation. Outgrowth of neurites from day 2 in vitro allows for developmental studies. Furthermore, the long-term survival of cultures (up to six weeks) makes them suitable for study of the slow, progressive degeneration of these neurons.

<table border="0" cellpadding="0" cellspacing="0" width="721">
	<tbody>
		<tr height="21">
			<td height="21" style="height:21px;width:364px;">Name of Material/ Equipment</td>
			<td style="width:71px;">Company</td>
			<td style="width:119px;">Catalog Number</td>
			<td style="width:167px;">Comments/Description</td>
		</tr>
		<tr height="21">
			<td height="21" style="height:21px;">Dulbecco&#39;s modified Eagle medium nutrient mixture F-12</td>
			<td>Invitrogen</td>
			<td>11330</td>
			<td></td>
		</tr>
		<tr height="21">
			<td height="21" style="height:21px;">Hanks&#39; Balanced Salt Solution (HBSS) (1X), liquid</td>
			<td>Invitrogen</td>
			<td>24020-117)</td>
			<td></td>
		</tr>
		<tr height="21">
			<td height="21" style="height:21px;">Fetal bovine serum, heat-inactivated (FBS)</td>
			<td>Invitrogen</td>
			<td>16140</td>
			<td></td>
		</tr>
		<tr height="21">
			<td height="21" style="height:21px;">N2 Supplement (100X), liquid</td>
			<td>Invitrogen</td>
			<td>17502-048)</td>
			<td></td>
		</tr>
		<tr height="21">
			<td height="21" style="height:21px;">D-(+)-Glucose solution (45% (wt/vol) in water</td>
			<td>Sigma</td>
			<td>G8769</td>
			<td></td>
		</tr>
		<tr height="21">
			<td height="21" style="height:21px;">Bovine serum albumin BSA</td>
			<td>Sigma</td>
			<td>A9430</td>
			<td></td>
		</tr>
		<tr height="21">
			<td height="21" style="height:21px;">Laminin from Engelbreth-Holm-Swarm murine sarcoma basement membrane</td>
			<td>Sigma</td>
			<td>L2020</td>
			<td></td>
		</tr>
		<tr height="21">
			<td height="21" style="height:21px;">Penicillin/streptomycin</td>
			<td>Invitrogen</td>
			<td>15070</td>
			<td></td>
		</tr>
		<tr height="21">
			<td height="21" style="height:21px;">Trypsin (0.05% (wt/vol)</td>
			<td>Invitrogen</td>
			<td>25300</td>
			<td></td>
		</tr>
		<tr height="21">
			<td height="21" style="height:21px;">Bovine serum albumin (BSA) cell culture tested</td>
			<td>Sigma&#160;</td>
			<td>A9418</td>
			<td></td>
		</tr>
		<tr height="21">
			<td height="21" style="height:21px;">Phosphate-buffered saline (PBS)</td>
			<td>Sigma</td>
			<td>P3813</td>
			<td></td>
		</tr>
		<tr height="21">
			<td height="21" style="height:21px;">Anti-Tyrosine hydroxylase (Th) antibody</td>
			<td>Pel-Freez Biologicals</td>
			<td>P60101-0&#160;</td>
			<td></td>
		</tr>
		<tr height="21">
			<td height="21" style="height:21px;">Poly-L-ornithine, 0.01% solution</td>
			<td>Sigma</td>
			<td>P4957</td>
			<td></td>
		</tr>
		<tr height="21">
			<td height="21" style="height:21px;">Anti-Map2 (Microtubule associated protein-2A and -2B) antibody</td>
			<td>Millipore</td>
			<td>MAB3418</td>
			<td></td>
		</tr>
		<tr height="21">
			<td height="21" style="height:21px;">Anti-Synapsin-1 antibody</td>
			<td>Millipore</td>
			<td>AB1543P</td>
			<td></td>
		</tr>
		<tr height="21">
			<td height="21" style="height:21px;">Alexa Fluor 488 donkey anti-rabbit IgG&#160;&#160; antibody</td>
			<td>Molecular Probes</td>
			<td>A-21206</td>
			<td></td>
		</tr>
		<tr height="21">
			<td height="21" style="height:21px;">Alexa Fluor 594 donkey anti-rabbit IgG&#160;&#160; antibody</td>
			<td>Molecular Probes</td>
			<td>A-21207</td>
			<td></td>
		</tr>
		<tr height="21">
			<td height="21" style="height:21px;">Alexa Fluor 488 donkey anti-sheep IgG&#160;&#160; antibody</td>
			<td>Molecular Probes</td>
			<td>A-11015</td>
			<td></td>
		</tr>
		<tr height="21">
			<td height="21" style="height:21px;">Alexa Fluor 594 donkey anti-sheep IgG&#160;&#160; antibody</td>
			<td>Molecular Probes</td>
			<td>A-11016</td>
			<td></td>
		</tr>
		<tr height="21">
			<td height="21" style="height:21px;">Alexa Fluor 594 donkey anti-mouse IgG&#160;&#160; antibody</td>
			<td>Molecular Probes</td>
			<td>A-21203</td>
			<td></td>
		</tr>
		<tr height="21">
			<td height="21" style="height:21px;">Trypan blue solution (0.4% (wt/vol)</td>
			<td>Biowhittaker</td>
			<td>17-942E</td>
			<td></td>
		</tr>
		<tr height="21">
			<td height="21" style="height:21px;">Stereo Microscope</td>
			<td>Carl Zeiss</td>
			<td>Stemi 2000-C</td>
			<td></td>
		</tr>
		<tr height="21">
			<td height="21" style="height:21px;">Inverted phase contrast microscope</td>
			<td>Carl Zeiss</td>
			<td>Axiovert 40 C</td>
			<td></td>
		</tr>
		<tr height="21">
			<td height="21" style="height:21px;">Dumont Forceps</td>
			<td>Fine Scientific Tools</td>
			<td>May-45</td>
			<td></td>
		</tr>
		<tr height="21">
			<td height="21" style="height:21px;">Cover Slip Forceps &#8211; Dumoxel</td>
			<td>Fine Scientific Tools</td>
			<td>11251-33</td>
			<td></td>
		</tr>
		<tr height="21">
			<td height="21" style="height:21px;">Two Dumont #45 Forceps &#8211; Dumoxel</td>
			<td>Fine Scientific Tools</td>
			<td>11245-30</td>
			<td></td>
		</tr>
		<tr height="21">
			<td height="21" style="height:21px;">Blade Holder/Breaker Flat Grip - 11cm</td>
			<td>Fine Scientific Tools</td>
			<td>10052-11</td>
			<td></td>
		</tr>
		<tr height="21">
			<td height="21" style="height:21px;">Student Iris Scissors - Straight 11.5cm</td>
			<td>Fine Scientific Tools</td>
			<td>91460-11</td>
			<td></td>
		</tr>
		<tr height="21">
			<td height="21" style="height:21px;">Fiber optic halogen illuminator</td>
			<td>Nikon</td>
			<td>MKII</td>
			<td></td>
		</tr>
		<tr height="21">
			<td height="21" style="height:21px;">Disposable Borosilicate Glass Pasteur Pipettes</td>
			<td>Fisherbrand</td>
			<td>13-678-20C</td>
			<td></td>
		</tr>
		<tr height="21">
			<td height="21" style="height:21px;">Hemocytometer</td>
			<td>Proscitech</td>
			<td>SVZ2NIOU</td>
			<td></td>
		</tr>
		<tr height="21">
			<td height="21" style="height:21px;">0.2 &#181;m sterile filter units</td>
			<td>Nalgene</td>
			<td>NL-CE-156-4020</td>
			<td></td>
		</tr>
		<tr height="21">
			<td height="21" style="height:21px;">100x20mm Petri dishes</td>
			<td>BD Biosciences</td>
			<td>351005</td>
			<td></td>
		</tr>
		<tr height="21">
			<td height="21" style="height:21px;">Round Cover Slip #1 Thickness German Glass 12mm</td>
			<td>Bellco Glass</td>
			<td>1943-10012&#160;</td>
			<td></td>
		</tr>
	</tbody>
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isolation, culture and long-term maintenance of primary mesencephalic dopaminergic neurons from embryonic rodent brains

Degeneration of mesencephalic dopaminergic (mesDA) neurons is the pathological hallmark of Parkinson&#8217;s diseae. Study of the biological processes involved in physiological functions and vulnerability and death of these neurons is imparative to understanding the underlying causes and unraveling the cure for this common neurodegenerative disorder. Primary cultures of mesDA neurons provide a tool for investigation of the molecular, biochemical and electrophysiological properties, in order to understand the development, long-term survival and degeneration of these neurons during the course of disease. Here we present a detailed method for the isolation, culturing and maintenance of midbrain dopaminergic neurons from E12.5 mouse (or E14.5 rat) embryos. Optimized cell culture conditions in this protocol result in presence of axonal and dendritic projections, synaptic connections and other neuronal morphological properties, which make the cultures suitable for study of the physiological, cell biological and molecular characteristics of this neuronal population.

Immunohistochemistry against Tyrosine hydroxylase (Th) shows that between 0.5-1% of the cells in culture are dopaminergic. Neuronal projections appear within 2 hr after plating and by the first day, axons and dendrites are distinguishable (Figure 2), using Tyrosine Hydroxylase (TH) and Microtubule-Associated Protein 2 (Map2) antibodies (Figure 3). The neurons survive for more than six weeks and show extensive outgrowth. The neuron-glia ratio in the cultures is directly related to the con...

Watch this Scientific Journal Video about Isolation, Culture and Long-Term Maintenance of Primary Mesencephalic Dopaminergic Neurons From Embryonic Rodent Brains at JoVE.com

Isolation, Culture and Long-Term Maintenance of Primary Mesencephalic Dopaminergic Neurons From Embryonic Rodent Brains

The causes of degeneration of midbrain dopaminergic neurons during Parkinson&#8217;s disease are not fully understood. Cellular culture systems provide an essential tool for study of the neurophysiological properties of these neurons. Here we present an optimized protocol, which can be utilized for in vitro modeling of neurodegeneration.

Degeneration of mesencephalic dopaminergic (mesDA) neurons is the pathological hallmark of Parkinson&#8217;s diseae. Study of the biological processes ...

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Research

JoVE Journal

Neuroscience

13.8K Views.  Imperial College London. The causes of degeneration of midbrain dopaminergic neurons during Parkinson’s disease are not fully understood. Cellular culture systems provide an essential tool for study of the neurophysiological properties of these neurons. Here we present an optimized protocol, which can be utilized for in vitro modeling of neurodegeneration.

Video: Isolation, Culture and Long-Term Maintenance of Primary Mesencephalic Dopaminergic Neurons From Embryonic Rodent Brains

Dissection and Culture of Commissural Neurons from Embryonic Spinal Cord

Commissural neurons have been widely used to investigate the mechanisms underlying axon guidance during embryonic spinal cord development. The cell bodies of these neurons are located in the dorsal spinal cord and their axons follow stereotyped trajectories during embryonic development. Commissural axons initially project ventrally towards the floorplate. After crossing the midline, these axons turn anteriorly and project towards the brain. Each of these steps is regulated by the action of several guidance cues. Cultures highly enriched in commissural neurons are ideally suited for many experiments addressing the mechanisms of axon pathfinding, including turning assays, immunochemistry and biochemistry. Here, we describe a method to dissect and culture commissural neurons from E13 rat dorsal spinal cord. First, the spinal cord is isolated and dorsal strips are dissected out. The dorsal tissue is then dissociated into a cell suspension by trypsinization and mechanical disruption. Neurons are plated onto poly-L-lysine-coated glass coverslips or tissue-culture dishes. After 30 hours in vitro, most neurons have extended an axon. The purity of the culture (Yam et al. 2009), typically over 90%, can be assessed by immunolabeling with the commissural neuron markers DCC, LH2 and TAG1 (Helms and Johnson, 1998). This neuronal preparation is a useful tool for in vitro studies of the cellular and molecular mechanisms of commissural axon growth and guidance during spinal cord development.

This video demonstrates a method to dissect and culture commissural neurons from E13 rat dorsal spinal cord. Dissociated commissural neurons are useful to study the cellular and molecular mechanisms of axon growth and guidance.

Commissural neurons have been widely used to investigate the mechanisms underlying axon guidance during embryonic spinal cord development. The cell bodies ...

Nucleofection and Primary Culture of Embryonic Mouse Hippocampal and Cortical Neurons

Hippocampal and cortical neurons have been used extensively to study central nervous system (CNS) neuronal polarization, axon/dendrite outgrowth, and synapse formation and function. An advantage of culturing these neurons is that they readily polarize, forming distinctive axons and dendrites, on a two dimensional substrate at very low densities. This property has made them extremely useful for determining many aspects of neuronal development. Furthermore, by providing glial conditioning for these neurons they will continue to develop, forming functional synaptic connections and surviving for several months in culture. In this protocol we outline a technique to dissect, culture and transfect embryonic mouse hippocampal and cortical neurons. Transfection is accomplished by electroporating DNA into the neurons before plating via nucleofection. This protocol has the advantage of expressing fluorescently-tagged fusion proteins early in development (~4-8hrs after plating) to study the dynamics and function of proteins during polarization, axon outgrowth and branching. We have also discovered that this single transfection before plating maintains fluorescently-tagged fusion protein expression at levels appropriate for imaging throughout the lifetime of the neuron (&gt; 2 months in culture). Thus, this methodology is useful for studying protein localization and function throughout CNS development with little or no disruption of neuronal function.

This protocol outlines the steps required to dissect, transfect via electroporation and culture mouse hippocampal and cortical neurons. Short-term cultures may be used for studies of axon outgrowth and guidance, while long-term cultures can be used for studies of synaptogenesis and dendritic spine analysis.

Hippocampal and cortical neurons have been used extensively to study central nervous system (CNS) neuronal polarization, axon/dendrite outgrowth, and ...

Isolation and Culture of Hippocampal Neurons from Prenatal Mice

Primary cultures of rat and murine hippocampal neurons are widely used to reveal cellular mechanisms in neurobiology. By isolating and growing individual neurons, researchers are able to analyze properties related to cellular trafficking, cellular structure and individual protein localization using a variety of biochemical techniques. Results from such experiments are critical for testing theories addressing the neural basis of memory and learning. However, unambiguous results from these forms of experiments are predicated on the ability to grow neuronal cultures with minimum contamination by other brain cell types. In this protocol, we use specific media designed for neuron growth and careful dissection of embryonic hippocampal tissue to optimize growth of healthy neurons while minimizing contaminating cell types (i.e. astrocytes). Embryonic mouse hippocampal tissue can be more difficult to isolate than similar rodent tissue due to the size of the sample for dissection. We show detailed dissection techniques of hippocampus from embryonic day 19 (E19) mouse pups. Once hippocampal tissue is isolated, gentle dissociation of neuronal cells is achieved with a dilute concentration of trypsin and mechanical disruption designed to separate cells from connective tissue while providing minimum damage to individual cells. A detailed description of how to prepare pipettes to be used in the disruption is included. Optimal plating densities are provided for immuno-fluorescence protocols to maximize successful cell culture. The protocol provides a fast (approximately 2 hr) and efficient technique for the culture of neuronal cells from mouse hippocampal tissue.

We provide a protocol for the culture of highly purified hippocampal neurons from prenatal mouse brains without the use of a feeder glial cell layer.

Primary cultures of rat and murine hippocampal neurons are widely used to reveal cellular mechanisms in neurobiology. By isolating and growing individual ...

Isolation and Culture of Endothelial Cells from the Embryonic Forebrain

Embryonic brain endothelial cells can serve as an important tool in the study of angiogenesis and neurovascular development and interactions. The two vascular networks of the embryonic forebrain, pial and periventricular, are spatially distinctive and have different origins and growth patterns. Endothelial cells from the pial and periventricular vascular networks have unique gene expression profiles and functions. Here we present a step-by-step protocol for isolation, culture, and verification of pure populations of endothelial cells from the periventricular vascular network (PVECs) of the embryonic forebrain (telencephalon). In this approach, telencephalon devoid of pial membrane obtained from embryonic day 15 mice is minced, digested with collagenase/dispase, and dispersed mechanically into a single cell suspension. PVECs are purified from cell suspension using positive selection with anti-CD-31/PECAM-1 antibody conjugated to MicroBeads using a strong magnetic separation method. Purified cells are cultured on collagen 1&#160;coated culture dishes in endothelial cell culture medium until they become confluent and further subcultured. PVECs obtained with this protocol exhibit cobblestone and spindle shaped phenotypes, as visualized by phase-contrast light microscopy and fluorescence microscopy. Purity of PVEC cultures was established with endothelial cell markers. In our hands, this method reliably and consistently yields pure populations of PVECs. This protocol will benefit studies aimed at gaining mechanistic insights into forebrain angiogenesis, understanding PVEC interactions, and cross-talks with neuronal cell types and holds tremendous potential for therapeutic angiogenesis.

This video demonstrates an easy and reliable strategy for preparation of pure cultures of endothelial cells from the embryonic forebrain within 10-12 days and will be useful for research focused on many aspects of cerebral angiogenesis.

Embryonic brain endothelial cells can serve as an important tool in the study of angiogenesis and neurovascular development and interactions. The two ...

Primary Culture of Mouse Dopaminergic Neurons

Dopaminergic neurons represent less than 1% of the total number of neurons in the brain. This low amount of neurons regulates important brain functions such as motor control, motivation, and working memory. Nigrostriatal dopaminergic neurons selectively degenerate in Parkinson&#39;s disease (PD). This progressive neuronal loss is unequivocally associated with the motors symptoms of the pathology (bradykinesia, resting tremor, and muscular rigidity). The main agent responsible of dopaminergic neuron degeneration is still unknown. However, these neurons appear to be extremely vulnerable in diverse conditions. Primary cultures constitute one of the most relevant models to investigate properties and characteristics of dopaminergic neurons. These cultures can be submitted to various stress agents that mimic PD pathology and to neuroprotective compounds in order to stop or slow down neuronal degeneration. The numerous transgenic mouse models of PD that have been generated during the last decade further increased the interest of researchers for dopaminergic neuron cultures. Here, the video protocol focuses on the delicate dissection of embryonic mouse brains. Precise excision of ventral mesencephalon is crucial to obtain neuronal cultures sufficiently rich in dopaminergic cells to allow subsequent studies. This protocol can be realized with embryonic transgenic mice and is suitable for immunofluorescence staining, quantitative PCR, second messenger quantification, or neuronal death/survival assessment.

Dopaminergic neurons play a vital regulatory role in the brain. Their loss is associated with Parkinson's disease. In this video, we show how to generate primary cultures of central dopaminergic neurons from embryonic mouse mesencephalon. Such cultures are useful to study the extreme vulnerability of these neurons to various stresses.

Dopaminergic neurons represent less than 1% of the total number of neurons in the brain. This low amount of neurons regulates important brain functions ...

Isolation and Culture of Dissociated Sensory Neurons From Chick Embryos

Neurons are multifaceted cells that carry information essential for a variety of functions including sensation, motor movement, learning, and memory. Studying neurons in vivo can be challenging due to their complexity, their varied and dynamic environments, and technical limitations. For these reasons, studying neurons in vitro can prove beneficial to unravel the complex mysteries of neurons. The well-defined nature of cell culture models provides detailed control over environmental conditions and variables. Here we describe how to isolate, dissociate, and culture primary neurons from chick embryos. This technique is rapid, inexpensive, and generates robustly growing sensory neurons. The procedure consistently produces cultures that are highly enriched for neurons and has very few non-neuronal cells (less than 5%). Primary neurons do not adhere well to untreated glass or tissue culture plastic, therefore detailed procedures to create two distinct, well-defined laminin-containing substrata for neuronal plating are described. Cultured neurons are highly amenable to multiple cellular and molecular techniques, including co-immunoprecipitation, live cell imagining, RNAi, and immunocytochemistry. Procedures for double immunocytochemistry on these cultured neurons have been optimized and described here.

Cell culture models provide detailed control over environmental conditions and thus provide a powerful platform to elucidate numerous aspects of neuronal cell biology. We describe a rapid, inexpensive, and reliable method to isolate, dissociate, and culture sensory neurons from chick embryos. Details of substrata preparation and immunocytochemistry are also provided.

Neurons are multifaceted cells that carry information essential for a variety of functions including sensation, motor movement, learning, and memory. ...

A Simplified Method for Ultra-Low Density, Long-Term Primary Hippocampal Neuron Culture

Culturing primary hippocampal neurons in vitro facilitates mechanistic interrogation of many aspects of neuronal development. Dissociated embryonic hippocampal neurons can often grow successfully on glass coverslips at high density under serum-free conditions, but low density cultures typically require a supply of trophic factors by co-culturing them with a glia feeder layer, preparation of which can be time-consuming and laborious. In addition, the presence of glia may confound interpretation of results and preclude studies on neuron-specific mechanisms. Here, a simplified method is presented for ultra-low density (~2,000 neurons/cm2), long-term (&#62;3 months) primary hippocampal neuron culture that is under serum free conditions and without glia cell support. Low density neurons are grown on poly-D-lysine coated coverslips, and flipped on high density neurons grown in a 24-well plate. Instead of using paraffin dots to create a space between the two neuronal layers, the experimenters can simply etch the plastic bottom of the well, on which the high density neurons reside, to create a microspace conducive to low density neuron growth. The co-culture can be easily maintained for &#62;3 months without significant loss of low density neurons, thus facilitating the morphological and physiological study of these neurons. To illustrate this successful culture condition, data are provided to show profuse synapse formation in low density cells after prolonged culture. This co-culture system also facilitates the survival of sparse individual neurons grown in islands of poly-D-lysine substrates and thus the formation of autaptic connections.

Low density cultures of primary hippocampal neurons usually require glia feeder layer to supply neurotrophic factors and sustain longevity. We describe here a simplified method to culture ultra-low density neurons on glass coverslips in the presence of a high density neuronal feeder layer, which facilitates investigation of specific neuronal-autonomous mechanisms.

Culturing primary hippocampal neurons in vitro facilitates mechanistic interrogation of many aspects of neuronal development. Dissociated embryonic ...

Spinal Cord Neurons Isolation and Culture from Neonatal Mice

We present a protocol for the isolation and culture of spinal cord neurons. The neurons are obtained from neonatal C57BL/6 mice and are isolated on postnatal day 1-3. A mouse litter, usually 4-10 pups born from one breeding pair, is gathered for one experiment, and spinal cords are collected individually from each mouse after euthanasia with isoflurane. The spinal column is dissected out and then the spinal cord is released from the column. The spinal cords are then minced to increase the surface area of delivery for an enzymatic protease that allows for the neurons and other cells to be released from the tissue. Trituration is then used to release the cells into solution. This solution is subsequently fractionated in a density gradient to separate the various cells in solution, allowing for neurons to be isolated. Approximately 1-2.5 x 106 neurons can be isolated from one litter group. The neurons are then seeded onto wells coated with adhesive factors that allow for proper growth and maturation. The neurons take approximately 7 days to reach maturity in the growth and culture medium and can be used thereafter for treatment and analysis.

This study presents a technique for the isolation of neurons from WT neonatal mice. It requires the careful dissection of the spinal cord from the neonatal mouse, followed by the separation of neurons from the spinal cord tissue through mechanical and enzymatic cleavage.

We present a protocol for the isolation and culture of spinal cord neurons. The neurons are obtained from neonatal C57BL/6 mice and are isolated on ...

Generation and Long-term Maintenance of Nerve-free Hydra

The interstitial cell lineage of Hydra includes multipotent stem cells, and their derivatives: gland cells, nematocytes, germ cells, and nerve cells. The interstitial cells can be eliminated through two consecutive treatments with colchicine, a plant-derived toxin that kills dividing cells, thus erasing the potential for renewal of the differentiated cells that are derived from the interstitial stem cells. This allows for the generation of Hydra that lack nerve cells. A nerve-free polyp cannot open its mouth to feed, egest, or regulate osmotic pressure. Such animals, however, can survive and be cultured indefinitely in the laboratory if regularly force-fed and burped. The lack of nerve cells allows for studies of the role of the nervous system in regulating animal behavior and regeneration. Previously published protocols for nerve-free Hydra maintenance involve outdated techniques such as mouth-pipetting with hand-pulled micropipette tips to feed and clean the Hydra. Here, an improved protocol for maintenance of nerve-free Hydra is introduced. Fine-tipped forceps are used to force open the mouth and insert freshly killed Artemia. Following force-feeding, the body cavity of the animal is flushed with fresh medium using a syringe and hypodermic needle to remove undigested material, referred to here as "burping". This new method of force-feeding and burping nerve-free Hydra through the use of forceps and syringes eliminates the need for mouth-pipetting using hand-pulled micropipette tips. It thus makes the process safer and significantly more time efficient. To ensure that the nerve cells in the hypostome have been eliminated, immunohistochemistry using anti-tyrosine-tubulin is conducted.

Generation and Long-term Maintenance of Nerve-free Hydra

Through a double treatment with colchicine, a plant-derived toxin that kills dividing cells, nerve-free Hydra vulgaris can be generated. These Hydra cannot feed or egest on their own. This paper describes an improved method for long-term maintenance of nerve free Hydra vulgaris in the laboratory.

The interstitial cell lineage of Hydra includes multipotent stem cells, and their derivatives: gland cells, nematocytes, germ cells, and nerve cells. The ...

Isolation and RNA Extraction of Neurons, Macrophages and Microglia from Larval Zebrafish Brains

To gain a detailed understanding of the role of different CNS cells during development or the establishment and progression of brain pathologies, it is important to isolate these cells without changing their gene expression profile. The zebrafish model provides a large number of transgenic fish lines in which specific cell types are labelled; for example neurons in the NBT:DsRed line or macrophages/microglia in the mpeg1:eGFP line. Furthermore, antibodies have been developed to stain specific cells, such as microglia with the 4C4 antibody.
Here, we describe the isolation of neurons, macrophages and microglia from larval zebrafish brains. Central to this protocol is the avoidance of an enzymatic tissue digestion at 37 &#176;C, which could modify cellular profiles. Instead a mechanical system of tissue homogenization at 4 &#176;C is used. This protocol entails homogenization of brains into cell suspension, their immuno-staining and the isolation of neurons, macrophages and microglia by FACS. Afterwards, we extracted RNA from those cells and evaluated their quality/quantity. We managed to obtain RNA of high quality (RNA Integrity Number (RIN) &#62; 7) to perform qPCR on macrophages/microglia and neurons, and transcriptomic analysis on microglia. This approach enables a better characterization of these cells, as well as a clearer understanding about their role in development and pathologies.

We present a protocol to isolate neurons, macrophages and microglia from larval zebrafish brains under physiological and pathological conditions. Upon isolation, RNA is extracted from these cells to analyze their gene expression profile. This protocol allows for the collection of high-quality RNA for performing downstream analysis like qPCR and transcriptomics.

To gain a detailed understanding of the role of different CNS cells during development or the establishment and progression of brain pathologies, it is ...