<p class="jove_content">We gratefully acknowledge Molecular Devices Analytical technologies/Arcturus for their generous donation of reagents used for the study. We also thank the Harvard Tissue Resource Center for providing postmortem human brain tissue. <strong>Funding</strong>: RO1MH76060 and P50MH080272.</p>

<ol>
	<li>Imbeaud, S., Graudens, E., Boulanger, V., Barlet, X., Zaborski, P., Eveno, E., Mueleer, O., Schroeder, A., Auffray, C. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Towards+standardization+of+RNA+quality+assessment+using+user-independent+classifiers+of+microcapillary+electrophoresis+traces.">Towards standardization of RNA quality assessment using user-independent classifiers of microcapillary electrophoresis traces.</a> <em style='font-style: italic'>Nucleic Acids Res</em>. <b>33</b>, e56-e56 (2005).</li></ol>

<p class="jove_content">The production of this video-article was sponsored by Life Technologies.</p>

<p class="jove_content">Here, we attempt to customize a protocol to extract homogeneous cell populations from heterogeneous postmortem brain tissue using the Arcturus XT system and related RNA extraction kits. As outlined above, we have made some modifications to the original protocols provided by the company, in order to maximize RNA integrity. The successful capturing of single cells depends solely on optimizing the steps prior to capture in order to achieve maximum cells with good RNA. These steps include the various parameters associated with tissue sectioning and staining. In short, with regards to tissue preparation these include: 1) decreasing the temperature gradient when sectioning, 2) only placing 2 sections per slide, 3) performing all dehydration steps on ice, 4) adding RNase Inhibitor to the stain, 5) increasing the dehydration duration in the final 100% ethanol to 3 minutes.</p>
<p class="jove_content">With regards to capturing, we feel that the combination of CapSure HS caps, with the software on Macro setting, should ensure optimal results. A humidity-controlled environment is critical to capturing single cells, as high humidity drastically reduces tissue "lift". High temperatures can also have a negative effect on RNA quality.</p>
<p class="jove_content">During the RNA isolation protocol with the PicoPure kit, there are two wash steps. It is important to check that all wash buffer is removed before transferring to another microcentrifuge tube for RNA elution, as any presence of the buffer in your final sample will result in less starting RNA for amplification. To ensure this, we centrifuge the final wash step for 2.5 minutes instead of 2 minutes as suggested in the protocol provided.</p>
<p class="jove_content">For the most part, the linear amplification protocol was according to the manufacturer's instructions. However, two crucial points should be taken into account when using this protocol: 1) try to limit loss of RNA via excess transferring of samples between tubes, by using only the 0.5ml tubes provided in conjunction with a 0.5ml block in the thermal cycler; and 2) when transferring the sample to the purification column for purification of cDNA, be sure to spin down the sample tubes after the first transfer. This will result in an additional 1-2ul of sample to add to the purification column and therefore can increase cDNA recovery.</p>
<p class="jove_content">When making use of the TURBO end-labeling kit for biotin-labeling of your limited aRNA samples, we suggest adding an extra few &mu;l's of water before the centrifugation step, to increase the labeled RNA yield extracted from the column. An extra minute of centrifugation will also help in this regard, especially if you are working with degraded tissue, such as FFPE tissue.</p>
<p class="jove_content">We feel confident that this protocol will enable the user to isolate small homogeneous structures, such as single cell populations, within heterogenous postmortem brain tissue. This reduces dilution effects of surrounding structures and other cell-types located in the various layers within the brain, leading to results targeted towards the specific cell types under investigation. As the quality of the resulting RNA is good enough for microarray studies, we can begin to pinpoint specific molecular signatures of specific cell populations affected in disease states.</p>

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		<div>
		<table border="1">
		<thead>
		<tr>
		<th>Material Name</th>
		<th>Type</th>
		<th>Company</th>
		<th>Catalogue Number</th>
		<th>Comment</th>
		</tr>
		</thead>
		<tbody>
		
<tr>
<td>4.5&#x201D; Forceps</td>
<td>&nbsp;</td>
<td>VWR</td>
<td>82027-392</td>
<td>&nbsp;</td>
<tr>
<td>Arcturus XT&trade; Laser-Capture Microdissection (LCM) System</td>
<td>&nbsp;</td>
<td>MDS Analytical Technologies</td>
<td>13821-00</td>
<td>&nbsp;</td>
<tr>
<td>CapSure&trade; HS LCM Caps</td>
<td>&nbsp;</td>
<td>MDS Analytical Technologies</td>
<td>LCM 0214</td>
<td>&nbsp;</td>
<tr>
<td>CapSure&reg; Macro LCM Caps</td>
<td>&nbsp;</td>
<td>MDS Analytical Technologies</td>
<td>LCM 0211</td>
<td>&nbsp;</td>
<tr>
<td>Experion&trade; Automated Electrophoresis Station</td>
<td>&nbsp;</td>
<td>Bio-Rad</td>
<td>700-7001</td>
<td>&nbsp;</td>
<tr>
<td>Experion&trade; RNA HighSens Chips</td>
<td>&nbsp;</td>
<td>Bio-Rad</td>
<td>700-7155</td>
<td>10 chips</td>
</tr>
<tr>
<td>Experion&#x2122; RNA HighSens Reagents</td>
<td>&nbsp;</td>
<td>Bio-Rad</td>
<td>700-7156</td>
<td>10 chips</td>
</tr>
<tr>
<td>Experion&#x2122; RNA StdSens Chips</td>
<td>&nbsp;</td>
<td>Bio-Rad</td>
<td>700-7153</td>
<td>10 chips</td>
</tr>
<tr>
<td>Experion&trade; RNA StdSens Reagents</td>
<td>&nbsp;</td>
<td>Bio-Rad</td>
<td>700-7154</td>
<td>10 chips</td>
</tr>
<tr>
<td>Falcon&reg;  polypropylene Conical tube</td>
<td>&nbsp;</td>
<td>Becton-Dickinson Labware</td>
<td>352070</td>
<td>&nbsp;</td>
<tr>
<td>GeneAmp&reg; thin-walled reaction tube with domed cap</td>
<td>&nbsp;</td>
<td>Applied Biosystems</td>
<td>N8010611</td>
<td>&nbsp;</td>
<tr>
<td>GeneChip&reg; Human X3P array</td>
<td>&nbsp;</td>
<td>Affymetrix</td>
<td>900516</td>
<td>6 chips</td>
</tr>
<tr>
<td>Histogene&reg; LCM Frozen Section Staining kit</td>
<td>&nbsp;</td>
<td>MDS Analytical Technologies</td>
<td>KIT0401</td>
<td>For staining solution, jars, ethanols and Xylene</td>
</tr>
<tr>
<td>Histogene&trade; LCM slides</td>
<td>&nbsp;</td>
<td>MDS Analytical Technologies</td>
<td>12231-00</td>
<td>&nbsp;</td>
<tr>
<td>Micro Slide Box</td>
<td>&nbsp;</td>
<td>VWR</td>
<td>48444-004</td>
<td>&nbsp;</td>
<tr>
<td>Microm HM 505E cryostat</td>
<td>&nbsp;</td>
<td>Thermo Scientific</td>
<td>22-050-350</td>
<td>Catalogue number for similar product as current product no longer available</td>
</tr>
<tr>
<td>Microprocessor Controlled 280 series Water bath</td>
<td>&nbsp;</td>
<td>Thermo Electron Corporation</td>
<td>51221048</td>
<td>Model 282</td>
</tr>
<tr>
<td>Molecular Sieve</td>
<td>&nbsp;</td>
<td>EMD&trade;</td>
<td>MX1583L-1</td>
<td>&nbsp;</td>
<tr>
<td>NanoDrop 1000 Spectrophotometer</td>
<td>&nbsp;</td>
<td>Thermo Scientific</td>
<td>n/a</td>
<td>The NanoDrop 1000 is not available anymore, but the NanoDrop 2000 is comparable.</td>
</tr>
<tr>
<td>Nuclease-free water</td>
<td>&nbsp;</td>
<td>Ambion&reg;</td>
<td>AM9932</td>
<td>&nbsp;</td>
<tr>
<td>PEN Membrane glass slides</td>
<td>&nbsp;</td>
<td>MDS Analytical Technologies</td>
<td>LCM 0522</td>
<td>&nbsp;</td>
<tr>
<td>PicoPure&reg; RNA Isolation kit</td>
<td>&nbsp;</td>
<td>MDS Analytical Technologies</td>
<td>KIT0204</td>
<td>&nbsp;</td>
<tr>
<td>RiboAmp&reg;HS<sup>PLUS</sup> with Biotin labeling</td>
<td>&nbsp;</td>
<td>MDS Analytical Technologies</td>
<td>KIT0511B</td>
<td>12 reactions Includes TURBO biotin labeling&trade; kit</td>
</tr>
<tr>
<td>RNase Zap&reg;</td>
<td>&nbsp;</td>
<td>Ambion&reg;</td>
<td>AM9780/2</td>
<td>&nbsp;</td>
<tr>
<td>RNase-Free DNase Set</td>
<td>&nbsp;</td>
<td>Qiagen</td>
<td>79254</td>
<td>&nbsp;</td>
<tr>
<td>RNasin&reg; Plus</td>
<td>&nbsp;</td>
<td>Promega</td>
<td>N261B</td>
<td>&nbsp;</td>
<tr>
<td>SuperScript&trade; III Reverse Transcriptase</td>
<td>&nbsp;</td>
<td>Invitrogen</td>
<td>18080-044</td>
<td>&nbsp;</td>		</tbody>
		</table>
		</div>
	

obtaining high quality rna from single cell populations in human postmortem brain tissue

<p class="jove_content">We proposed to investigate the gray matter reduction in the superior temporal gyrus seen in schizophrenia patients, by interrogating gene expression profiles of pyramidal neurons in layer III. It is well known that the cerebral cortex is an exceptionally heterogeneous structure comprising diverse regions, layers and cell types, each of which is characterized by distinct cellular and molecular compositions and therefore differential gene expression profiles. To circumvent the confounding effects of tissue heterogeneity, we used laser-capture microdissection (LCM) in order to isolate our specific cell-type i.e pyramidal neurons.</p>
<p class="jove_content">Approximately 500 pyramidal neurons stained with the Histogene staining solution were captured using the Arcturus XT LCM system. RNA was then isolated from captured cells and underwent two rounds of T7-based linear amplification using Arcturus/Molecular Devices kits. The Experion LabChip (Bio-Rad) gel and electropherogram indicated good quality a(m)RNA, with a transcript length extending past 600nt required for microarrays. The amount of mRNA obtained averaged 51&mu;g, with acceptable mean sample purity as indicated by the A260/280 ratio, of 2.5. Gene expression was profiled using the Human X3P GeneChip probe array from Affymetrix.</p>

Watch this Scientific Journal Video about Obtaining High Quality RNA from Single Cell Populations in Human Postmortem Brain Tissue at JoVE.com

Obtaining High Quality RNA from Single Cell Populations in Human Postmortem Brain Tissue

<p class="jove_content">We describe a process using laser-capture microdissection to isolate and extract RNA from a homogeneous cell population, pyramidal neurons, in layer III of the superior temporal gyrus in postmortem human brains. We subsequently linearly amplify (T7-based) mRNA, and hybridize the sample to the Affymetrix human X3P microarray. </p>

We proposed to investigate the gray matter reduction in the superior temporal gyrus seen in schizophrenia patients, by interrogating gene expression ...

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30.5K Views.  McLean Hospital. We describe a process using laser-capture microdissection to isolate and extract RNA from a homogeneous cell population, pyramidal neurons, in layer III of the superior temporal gyrus in postmortem human brains. We subsequently linearly amplify (T7-based) mRNA, and hybridize the sample to the Affymetrix human X3P microarray. 