The authors thank previous laboratory members who contributed to refinement of this protocol and the NIH for support over the years (DA19808 and DA15014 to OM). Anna Abt1 is a fellow of the "Interdisciplinary and Translational Research Training in neuroAIDS" (T32-MH078795); thus, this work was supported in part by the National Institutes of Health under Ruth L. Kirschstein National Research Service Award 5T32MH079785.

1. Glia Dissection (~2 weeks before plating neurons)
<ol>
	<li>To prepare for the dissection place sterile tools in 70% ethanol, add 4 mL cold dissection medium to 60 mm dishes (one dish per brain), and place 2.5% trypsin and DNase on ice to thaw (see details about surgical tools in table VI).</li>
	<li>Use large scissors to decapitate 2-4 day old pups and place heads in a 100 mm sterile dish.</li>
	<li>Use medium scissors to make a midline cut through the skin and pull back the skin to expose the skull. Use curved sci...

<ol>
	<li>Cook, A. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Interactions+between+chemokines:+regulation+of+fractalkine/CX3CL1+homeostasis+by+SDF/CXCL12+in+cortical+neurons.">Interactions between chemokines: regulation of fractalkine/CX3CL1 homeostasis by SDF/CXCL12 in cortical neurons.</a> J. Biol. Chem. 285, 10563-10563 (2010).</li><li>Nicolai, J., Burbassi, S., Rubin, J., Meucci, O. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=CXCL12+inhibits+expression+of+the+NMDA+receptor's+NR2B+subunit+through+a+histone+deacetylase-dependent+pathway+contributing+to+neuronal+survival.">CXCL12 inhibits expression of the NMDA receptor's NR2B subunit through a histone deacetylase-dependent pathway contributing to neuronal survival.</a> Cell. Death. Dis. 1, e33-e33 (2010).</li><li>Sengupta, R. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Morphine+increases+brain+levels+of+ferritin+heavy+chain+leading+to+inhibition+of+CXCR4-mediated+survival+signaling+in+neurons.">Morphine increases brain levels of ferritin heavy chain leading to inhibition of CXCR4-mediated survival signaling in neurons.</a> J. Neurosci. 29, 2534-2544 (2009).</li><li>Meucci, O. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Chemokines+regulate+hippocampal+neuronal+signaling+and+gp120+neurotoxicity.">Chemokines regulate hippocampal neuronal signaling and gp120 neurotoxicity.</a> Proc. Natl. Acad. Sci. U. S. A. 95, 14500-14500 (1998).</li><li>Khan, M. Z. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Regulation+of+neuronal+P53+activity+by+CXCR+4.">Regulation of neuronal P53 activity by CXCR 4.</a> Mol. Cell. Neurosci. 30, 58-66 (2005).</li><li>Patel, J. P. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Modulation+of+neuronal+CXCR4+by+the+micro-opioid+agonist+DAMGO.">Modulation of neuronal CXCR4 by the micro-opioid agonist DAMGO.</a> J. Neurovirol. 12, 492-500 (2006).</li><li>Shimizu, S. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Role+of+the+transcription+factor+E2F1+in+CXCR4-mediated+neurotoxicity+and+HIV+neuropathology.">Role of the transcription factor E2F1 in CXCR4-mediated neurotoxicity and HIV neuropathology.</a> Neurobiol. Dis. 25, 17-26 (2007).</li><li>Khan, M. Z. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=The+chemokine+receptor+CXCR4+regulates+cell-cycle+proteins+in+neurons.">The chemokine receptor CXCR4 regulates cell-cycle proteins in neurons.</a> J. Neurovirol. 9, 300-314 (2003).</li><li>Khan, M. Z. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=The+chemokine+CXCL12+promotes+survival+of+postmitotic+neurons+by+regulating+Rb+protein.">The chemokine CXCL12 promotes survival of postmitotic neurons by regulating Rb protein.</a> Cell. Death. Differ. 15, 1663-1672 (2008).</li><li>Khan, M. Z., Vaidya, A., Meucci, O. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=CXCL12-mediated+regulation+of+ANP32A/Lanp,+a+component+of+the+inhibitor+of+histone+acetyl+transferase+(INHAT)+complex,+in+cortical+neurons.">CXCL12-mediated regulation of ANP32A/Lanp, a component of the inhibitor of histone acetyl transferase (INHAT) complex, in cortical neurons.</a> J. Neuroimmune. Pharmacol. 6, 163-170 (2011).</li><li>Dotti, C. G., Sullivan, C. A., Banker, G. A. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=The+establishment+of+polarity+by+hippocampal+neurons+in+culture.">The establishment of polarity by hippocampal neurons in culture.</a> J. Neurosci. 8, 1454-1468 (1988).</li><li>Kaech, S., Banker, G. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Culturing+hippocampal+neurons.">Culturing hippocampal neurons.</a> Nat. Protoc. 1, 2406-2415 (2006).</li><li>Goslin, K., Banker, G., Goslin, K., Banker, G. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=.">.</a> Culturing Nerve Cells. , 339-370 (1998).</li><li>D'Ambrosio, J., Fatatis, A. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Osteoblasts+modulate+Ca2++signaling+in+bone-metastatic+prostate+and+breast+cancer+cells.">Osteoblasts modulate Ca2+ signaling in bone-metastatic prostate and breast cancer cells.</a> Clin. Exp. Metastasis. 26, 955-964 (2009).</li></ol>

No conflicts of interest declared.

This protocol provides a method for culturing rat primary cortical neurons in the presence of glia cells, while allowing the neurons to be easily isolated for experimental analysis. The glia support development of a healthy neuronal phenotype, while also modulating neuronal responses to experimental treatments in a physiologically relevant manner. Additionally, by passaging the primary glia before culturing with neurons this cell population becomes selectively enriched in astrocytes, thereby preventing inflammatory micro...

<table border="1">
	<tbody>
		<tr>
			<th>
				Reagent</th>
			<th>
				Concentration</th>
		</tr>
		<tr>
			<td>Glucose</td>
			<td>16 mM</td>
		</tr>
		<tr>
			<td>Sucrose</td>
			<td>22 mM</td>
		</tr>
		<tr>
			<td>NaCl</td>
			<td>135 mM</td>
		</tr>
		<tr>
			<td>KCl</td>
			<td>5 mM</td>
		</tr>
		<tr>
			<td>Na2HPO4</td>
			<td>1 mM</td>
		</tr>
		<tr>
			<td>KH2PO4</td>
			<td>0.22 mM</td>
		</tr>
		<tr>
			<td>HEPES</td>
			<td>10 mM</td>
		</tr>
		<tr>
			<td>pH</td>
			<td>7.4</td>
		</tr>
		<tr>
			<td>Osmolarity</td>
			<td>310&plusmn;10 mOsm</td>
		</tr>
	</tbody>
</table>
Table 1. Dissection Medium.
<table border="1">
	<tbody>
		<tr>
			<th>
				Reagent</th>
			<th>
				Concentration</th>
		</tr>
		<tr>
			<td>DMEM</td>
			<td>90%</td>
		</tr>
		<tr>
			<td>FBS</td>
			<td>10%</td>
		</tr>
		<tr>
			<td>Gentamicin</td>
			<td>50 &mu;g/mL</td>
		</tr>
	</tbody>
</table>
Tabe 2. Glia Plating Medium.
<table border="1">
	<tbody>
		<tr>
			<th>
				Reagent</th>
			<th>
				Concentration</th>
		</tr>
		<tr>
			<td>DMEM</td>
			<td>90%</td>
		</tr>
		<tr>
			<td>Horse Serum</td>
			<td>10%</td>
		</tr>
	</tbody>
</table>
Table 3. Neuron Plating Medium.
<table>
	<tbody>
		<tr>
			<th>
				Reagent</th>
			<th>
				Concentration</th>
		</tr>
		<tr>
			<td>DMEM</td>
			<td>98%</td>
		</tr>
		<tr>
			<td>N2 Supplement</td>
			<td>1%</td>
		</tr>
		<tr>
			<td>1M HEPES</td>
			<td>1%</td>
		</tr>
		<tr>
			<td>Ovalbumin</td>
			<td>50 mg/100mL</td>
		</tr>
	</tbody>
</table>
Table 4. N2 Medium.
<table border="1">
	<tbody>
		<tr>
			<th>
				Reagent</th>
			<th>
				Concentration</th>
		</tr>
		<tr>
			<td>Boric Acid</td>
			<td>50 mM</td>
		</tr>
		<tr>
			<td>Sodium Borate</td>
			<td>12.5 mM</td>
		</tr>
	</tbody>
</table>
Table 5. Borate Buffer (for poly-lysine).
<table border="1">
	<tbody>
		<tr>
			<th>
				Reagent</th>
			<th>
				Company</th>
			<th>
				Catalogue number</th>
		</tr>
		<tr>
			<td>High glucose Dulbecco's Modified Eagle 
			Medium (DMEM)</td>
			<td>Invitrogen</td>
			<td>11995-073</td>
		</tr>
		<tr>
			<td>Fetal Bovine Serum (FBS), Heat-inactivated</td>
			<td>Hyclone</td>
			<td>26400-044</td>
		</tr>
		<tr>
			<td>Horse Serum, Heat-inactivated</td>
			<td>Hyclone</td>
			<td>H1138</td>
		</tr>
		<tr>
			<td>Gentamicin (50mg/mL)</td>
			<td>Invitrogen</td>
			<td>15750-060</td>
		</tr>
		<tr>
			<td>N2 Supplement (100x)</td>
			<td>Invitrogen</td>
			<td>17502-048</td>
		</tr>
		<tr>
			<td>HEPES buffer solution</td>
			<td>Invitrogen</td>
			<td>15630-080</td>
		</tr>
		<tr>
			<td>Albumin from chicken egg white, Grade VI 
			(Ovalbumin)</td>
			<td>Sigma-Aldrich</td>
			<td>A2512</td>
		</tr>
		<tr>
			<td>2.5% Trypsin</td>
			<td>Invitrogen</td>
			<td>15090-046</td>
		</tr>
		<tr>
			<td>0.5% Trypsin-EDTA (10X)</td>
			<td>Invitrogen</td>
			<td>15400-054</td>
		</tr>
		<tr>
			<td>Deoxyribonuclease I from bovine pancreas 
			(DNase)</td>
			<td>Sigma-Aldrich</td>
			<td>D-5025</td>
		</tr>
		<tr>
			<td>Paraplast</td>
			<td>Fisher</td>
			<td>12-646-106</td>
		</tr>
		<tr>
			<td>Poly-L-lysine</td>
			<td>Sigma-Aldrich</td>
			<td>P1274</td>
		</tr>
		<tr>
			<td>Cytosine-&beta;-D-arabinofuranoside hydrochloride</td>
			<td>Sigma-Aldrich</td>
			<td>C6645</td>
		</tr>
		<tr>
			<td>Stereomicroscope</td>
			<td>Leica</td>
			<td>Leica ZOOM 2000</td>
		</tr>
		<tr>
			<td>Cover glasses, Circles, 15 mm, Thickness 
			0.13-0.17 mm</td>
			<td>Carolina</td>
			<td>633031</td>
		</tr>
		<tr>
			<td>Thermanox sheets</td>
			<td>Grace BioLabs</td>
			<td>HS4550</td>
		</tr>
		<tr>
			<td>Large forceps</td>
			<td>Biomedical 
			Research 
			Instruments</td>
			<td>70-4000</td>
		</tr>
		<tr>
			<td>Fine-tipped No.5 forceps</td>
			<td>Fine Science 
			Tools</td>
			<td>91150-20</td>
		</tr>
		<tr>
			<td>Pattern No.1 forceps</td>
			<td>Biomedical 
			Research</td>
			<td>10-1400</td>
		</tr>
		<tr>
			<td>&nbsp;</td>
			<td>Instruments</td>
			<td>&nbsp;</td>
		</tr>
		<tr>
			<td>Scissors, straight, sharp-blunt</td>
			<td>Biomedical 
			Research 
			Instruments</td>
			<td>28-1435</td>
		</tr>
		<tr>
			<td>Micro Dissecting scissors</td>
			<td>Biomedical 
			Research 
			Instruments</td>
			<td>11-2070</td>
		</tr>
		<tr>
			<td>Micro Dissecting Curved scissors</td>
			<td>Biomedical 
			Research 
			Instruments</td>
			<td>11-1395</td>
		</tr>
	</tbody>
</table>

bilaminar co-culture of primary rat cortical neurons and glia

This video will guide you through the process of culturing rat cortical neurons in the presence of a glial feeder layer, a system known as a bilaminar or co-culture model. This system is suitable for a variety of experimental needs requiring either a glass or plastic growth substrate and can also be used for culture of other types of neurons.
Rat cortical neurons obtained from the late embryonic stage (E17) are plated on glass coverslips or tissue culture dishes facing a feeder layer of glia grown on dishes or plastic coverslips (known as Thermanox), respectively. The choice between the two configurations depends on the specific experimental technique used, which may require, or not, that neurons are grown on glass (e.g. calcium imaging versus Western blot). The glial feeder layer, an astroglia-enriched secondary culture of mixed glia, is separately prepared from the cortices of newborn rat pups (P2-4) prior to the neuronal dissection.
A major advantage of this culture system as compared to a culture of neurons only is the support of neuronal growth, survival, and differentiation provided by trophic factors secreted from the glial feeder layer, which more accurately resembles the brain environment in vivo. Furthermore, the co-culture can be used to study neuronal-glial interactions1.
At the same time, glia contamination in the neuronal layer is prevented by different means (low density culture, addition of mitotic inhibitors, lack of serum and use of optimized culture medium) leading to a virtually pure neuronal layer, comparable to other established methods1-3. Neurons can be easily separated from the glial layer at any time during culture and used for different experimental applications ranging from electrophysiology4, cellular and molecular biology5-8, biochemistry5, imaging and microscopy4,6,7,9,10. The primary neurons extend axons and dendrites to form functional synapses11, a process which is not observed in neuronal cell lines, although some cell lines do extend processes.
A detailed protocol of culturing rat hippocampal neurons using this co-culture system has been described previously4,12,13. Here we detail a modified protocol suited for cortical neurons. As approximately 20x106 cells are recovered from each rat embryo, this method is particularly useful for experiments requiring large numbers of neurons (but not concerned about a highly homogenous neuronal population). The preparation of neurons and glia needs to be planned in a time-specific manner. We will provide the step-by-step protocol for culturing rat cortical neurons as well as culturing glial cells to support the neurons.

Watch this Scientific Journal Video about Bilaminar Co-culture of Primary Rat Cortical Neurons and Glia at JoVE.com

Bilaminar Co-culture of Primary Rat Cortical Neurons and Glia

Here we provide a protocol for culturing rat cortical neurons in the presence of a glial feeder layer. The cultured neurons establish polarity and create synapses, and can be separated from the glia for use in various applications, such as electrophysiology, calcium imaging, cell survival assays, immunocytochemistry, and RNA/DNA/protein isolation.

This video will guide you through the process of culturing rat cortical neurons in the presence of a glial feeder layer, a system known as a bilaminar or ...

bilaminar-co-culture-of-primary-rat-cortical-neurons-and-glia

Research

JoVE Journal

Neuroscience

19.4K Views.  Drexel University College of Medicine. Here we provide a protocol for culturing rat cortical neurons in the presence of a glial feeder layer. The cultured neurons establish polarity and create synapses, and can be separated from the glia for use in various applications, such as electrophysiology, calcium imaging, cell survival assays, immunocytochemistry, and RNA/DNA/protein isolation.