This work was supported by NIH grant P20 GM109098 and the Innovation Award Program from Praespero to Edwin Wan. Flow Cytometry experiments were performed in the WVU Flow Cytometry &#38; Single Cell Core Facility, which is&#160;supported by NIH grants S10 OD016165, U57 GM104942, P30 GM103488, and P20 GM103434.

All protocols and procedures performed were approved by the Institutional Animal Care and Use Committee (IACUC) of West Virginia University. The mice were housed under specific-pathogen-free conditions in the vivarium at West Virginia University. &#160;
1. Preparation of solutions
<ol>
	<li>Prepare perfusion buffer (phosphate buffered saline, PBS). Use approximately two 10 mL aliquots of ice-cold PBS per mouse.</li>
	<li>Prepare lung cell medium/FACS buffer. FACS buffer contains PBS suppleme...

<ol>
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S., Zhao, A., Sun, B., Jiang, W., Ji, S. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Multiplex+Cytokine+Profiling+of+Stimulated+Mouse+Splenocytes+Using+a+Cytometric+Bead-based+Immunoassay+Platform.">Multiplex Cytokine Profiling of Stimulated Mouse Splenocytes Using a Cytometric Bead-based Immunoassay Platform.</a> Journal of Visualized Experiments. (129), e56440 (2017).</li><li>Shi, C., Pamer, E. G. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Monocyte+recruitment+during+infection+and+inflammation.">Monocyte recruitment during infection and inflammation.</a> Nature Reviews Immunology. 11 (11), 762-774 (2011).</li><li>Monaghan, K. L., Zheng, W., Hu, G., Wan, E. C. K. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Monocytes+and+Monocyte-Derived+Antigen-Presenting+Cells+Have+Distinct+Gene+Signatures+in+Experimental+Model+of+Multiple+Sclerosis.">Monocytes and Monocyte-Derived Antigen-Presenting Cells Have Distinct Gene Signatures in Experimental Model of Multiple Sclerosis.</a> Frontiers in Immunology. 10, 2779 (2019).</li><li>Zhai, X., 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=A+novel+technique+to+prepare+a+single+cell+suspension+of+isolated+quiescent+human+hepatic+stellate+cells.">A novel technique to prepare a single cell suspension of isolated quiescent human hepatic stellate cells.</a> Science Reports. 9 (1), 12757 (2019).</li><li>Platzer, B., 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=Dendritic+cell-bound+IgE+functions+to+restrain+allergic+inflammation+at+mucosal+sites.">Dendritic cell-bound IgE functions to restrain allergic inflammation at mucosal sites.</a> Mucosal Immunology. 8 (3), 516-532 (2015).</li><li>Shinoda, K., 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=Thy1+IL-7++lymphatic+endothelial+cells+in+iBALT+provide+a+survival+niche+for+memory+T-helper+cells+in+allergic+airway+inflammation.">Thy1+IL-7+ lymphatic endothelial cells in iBALT provide a survival niche for memory T-helper cells in allergic airway inflammation.</a> Proceedings of the National Academy of Sciences U. S. A. 113 (20), 2842-2851 (2016).</li><li>Nakahashi-Oda, C., 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=Apoptotic+epithelial+cells+control+the+abundance+of+Treg+cells+at+barrier+surfaces.">Apoptotic epithelial cells control the abundance of Treg cells at barrier surfaces.</a> Nature Immunology. 17 (4), 441-450 (2016).</li><li>Barrott, J. 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The authors have nothing to disclose.

The protocols described here allow for the identification of lung immune cell types and the expression of chemokines or cytokines in the same mouse. If a histopathology study is desired, an individual lobe can be removed and fixed for that purpose prior to proceeding to the single cell isolation steps. One limitation of this method is that this approach may not be suitable in some disease settings if the change in the immune cell composition and the expression of chemokines and/or cytokines are anticipated to be unequall...

The lungs are a barrier organ, exposed to the external environment and, therefore, are constantly receiving immunological challenges such as pathogens and allergens1. The activation of lung-resident immune cells and the infiltration of immune cells from the periphery are required to clear pathogens from the pulmonary environment. Additionally, lung-resident immune cells maintain tolerance to commensal bacteria, suggesting that these cells play a role in pathogen clearance and maintaining homeostasis1. Alveolar and interstitial macrophages are among the lung-resident sentinel immune cells that sense pathogens via pattern recognition receptors and clear these pathogens by phagocytosis2. Lung-resident dendritic cells bridge the innate and adaptive immune response through antigen presentation3. In addition, activated local innate immune cells produce cytokines and chemokines that amplify the inflammatory response and stimulate the infiltration of immune cells such as monocytes, neutrophils, and lymphocytes into the lungs1. Ischemic stroke has been shown to modify systemic immunity and lead to increased susceptibility to pulmonary infection; however, few studies have evaluated the pulmonary compartment following ischemic stroke, though some studies have examined it during &#160;inflammatory conditions4,5,6,7,8,9. The goal of the methods described herein is to simultaneously determine lung pathology, immune cell composition, and the levels of cytokine and chemokine expression in the lungs to evaluate alterations to the pulmonary compartment and assess potential alterations to the pulmonary immune response following ischemic attack.
Described here is a protocol for obtaining single cell suspensions from the lungs of the mice to identify 13 types of immune cells. This protocol is based on tissue digestion with collagenase D without the need of an automated tissue dissociator. Additionally, we developed a protocol to prepare tissue homogenates that can be used to determine the expression levels of 13 different cytokines or chemokines using flow cytometry-based multiplex bead arrays. This protocol was successfully used to investigate the effects of ischemic stroke on pulmonary immunity and can be used in other disease models as well.

<table border="0" cellpadding="0" cellspacing="0" style="width:932px;" width="931">
	<colgroup>
		<col />
		<col />
		<col />
		<col />
	</colgroup>
	<tbody>
		<tr height="21">
			<td height="21" style="height:21px;width:289px;">B220-APC, clone RA3-6B2</td>
			<td style="width:129px;">Biolegend</td>
			<td style="width:101px;">103212</td>
			<td style="width:412px;">1:200 dilution</td>
		</tr>
		<tr height="42">
			<td height="42" style="height:42px;width:289px;">Beadbug 3 position bead homogenizer</td>
			<td style="width:129px;">Benchmark Scientific</td>
			<td style="width:101px;">D1030</td>
			<td>Tissue homogenizer</td>
		</tr>
		<tr height="21">
			<td height="21" style="height:21px;width:289px;">CCR2-BV421, clone SA203G11</td>
			<td style="width:129px;">Biolegend</td>
			<td style="width:101px;">150605</td>
			<td>1:200 dilution</td>
		</tr>
		<tr height="21">
			<td height="21" style="height:21px;width:289px;">CD103-BV421, clone 2E7</td>
			<td style="width:129px;">Biolegend</td>
			<td style="width:101px;">121422</td>
			<td>1:200 dilution</td>
		</tr>
		<tr height="21">
			<td height="21" style="height:21px;width:289px;">CD11b-PE/Cy7, clone M1/70</td>
			<td style="width:129px;">Biolegend</td>
			<td style="width:101px;">101216</td>
			<td>1:400 dilution</td>
		</tr>
		<tr height="21">
			<td height="21" style="height:21px;width:289px;">CD11c-PE/Cy7, clone N418</td>
			<td style="width:129px;">Biolegend</td>
			<td style="width:101px;">117318</td>
			<td>1:200 dilution</td>
		</tr>
		<tr height="21">
			<td height="21" style="height:21px;width:289px;">CD11c-Percp/Cy5.5, clone N418</td>
			<td style="width:129px;">Biolegend</td>
			<td style="width:101px;">117328</td>
			<td>1:200 dilution</td>
		</tr>
		<tr height="21">
			<td height="21" style="height:21px;width:289px;">CD4-BV421, clone GK1.5</td>
			<td style="width:129px;">Biolegend</td>
			<td style="width:101px;">100443</td>
			<td>1:200 dilution</td>
		</tr>
		<tr height="21">
			<td height="21" style="height:21px;width:289px;">CD45-FITC, clone 30-F11</td>
			<td style="width:129px;">Biolegend</td>
			<td style="width:101px;">103108</td>
			<td>1:200 dilution</td>
		</tr>
		<tr height="21">
			<td height="21" style="height:21px;width:289px;">CD64-APC, clone X54-5/7.1</td>
			<td style="width:129px;">Biolegend</td>
			<td style="width:101px;">139306</td>
			<td>1:200 dilution</td>
		</tr>
		<tr height="21">
			<td height="21" style="height:21px;width:289px;">CD8-PE, clone 53-6.7</td>
			<td style="width:129px;">Biolegend</td>
			<td style="width:101px;">100708</td>
			<td>1:800 dilution</td>
		</tr>
		<tr height="21">
			<td height="21" style="height:21px;width:289px;">Collagenase D</td>
			<td style="width:129px;">Sigma Aldrich</td>
			<td>11088882001</td>
			<td>Component in the dissociation buffer</td>
		</tr>
		<tr height="21">
			<td height="21" style="height:21px;width:289px;">Conical screw cap tube</td>
			<td style="width:129px;">ThermoFisher</td>
			<td style="width:101px;">02-681-344</td>
			<td>Tube for tissue homogenization</td>
		</tr>
		<tr height="21">
			<td height="21" style="height:21px;width:289px;">DNase I</td>
			<td style="width:129px;">Sigma Aldrich</td>
			<td>10104159001</td>
			<td>Component in the dissociation buffer</td>
		</tr>
		<tr height="21">
			<td height="21" style="height:21px;width:289px;">Fc block CD16/32 antibody</td>
			<td style="width:129px;">Biolegend</td>
			<td style="width:101px;">101320</td>
			<td>1:100 dilution</td>
		</tr>
		<tr height="21">
			<td height="21" style="height:21px;width:289px;">genlteMACS dissociator</td>
			<td style="width:129px;">Miltenyi Biotec</td>
			<td>130-093-235</td>
			<td>Comparsion of lung digestion with or without mechanical dissociator</td>
		</tr>
		<tr height="21">
			<td height="21" style="height:21px;width:289px;">gentleMACS C tubes</td>
			<td style="width:129px;">Miltenyi Biotec</td>
			<td style="width:101px;">130-093-237</td>
			<td>Tube for tissue disscoiation with genlteMACS dissociator</td>
		</tr>
		<tr height="42">
			<td height="42" style="height:42px;width:289px;">Halt protease and phosphatase inhibitor cocktial</td>
			<td style="width:129px;">ThermoFisher</td>
			<td style="width:101px;">78442</td>
			<td>Component in the homogenization buffer</td>
		</tr>
		<tr height="42">
			<td height="42" style="height:42px;width:289px;">Laser doppler monitor</td>
			<td style="width:129px;">Moor</td>
			<td style="width:101px;">MOORVMS-LDF</td>
			<td>Blood flow monitoring during tMCAO</td>
		</tr>
		<tr height="42">
			<td height="42" style="height:42px;width:289px;">LEGENDplex proinflammatory chemokine panel</td>
			<td style="width:129px;">Biolegend</td>
			<td style="width:101px;">740451</td>
			<td>Multiplex bead array</td>
		</tr>
		<tr height="21">
			<td height="21" style="height:21px;width:289px;">LIVE/DEAD fixable near-IR stain</td>
			<td style="width:129px;">ThermoFisher</td>
			<td style="width:101px;">L34976</td>
			<td>Use for dead cell exclusion during flow cytometric analysis</td>
		</tr>
		<tr height="21">
			<td height="21" style="height:21px;width:289px;">Ly6C-PE, clone HK1.4</td>
			<td style="width:129px;">Biolegend</td>
			<td style="width:101px;">128008</td>
			<td>1:800 dilution</td>
		</tr>
		<tr height="21">
			<td height="21" style="height:21px;width:289px;">Ly6G-BV510, clone 1A8</td>
			<td style="width:129px;">Biolegend</td>
			<td style="width:101px;">127633</td>
			<td>1:200 dilution</td>
		</tr>
		<tr height="42">
			<td height="42" style="height:42px;width:289px;">MCAO suture L56 reusable 6-0 medium</td>
			<td style="width:129px;">Doccol</td>
			<td style="width:101px;">602356PK10Re</td>
			<td>tMCAO</td>
		</tr>
		<tr height="21">
			<td height="21" style="height:21px;width:289px;">MHC II-BV510, clone M5/114.15.2</td>
			<td style="width:129px;">Biolegend</td>
			<td style="width:101px;">107636</td>
			<td>1:800 dilution</td>
		</tr>
		<tr height="21">
			<td height="21" style="height:21px;width:289px;">NK1.1-Percp/Cy5.5, clone PK136</td>
			<td style="width:129px;">Biolegend</td>
			<td style="width:101px;">108728</td>
			<td>1:200 dilution</td>
		</tr>
		<tr height="21">
			<td height="21" style="height:21px;width:289px;">Siglec F-PE, clone E50-2440</td>
			<td style="width:129px;">BD Biosciences</td>
			<td style="width:101px;">552126</td>
			<td>1:200 dilution</td>
		</tr>
		<tr height="21">
			<td height="21" style="height:21px;width:289px;">Silk suture thread, size 6/0</td>
			<td style="width:129px;">Fine Science Tools</td>
			<td style="width:101px;">18020-60</td>
			<td>tMCAO</td>
		</tr>
		<tr height="21">
			<td height="21" style="height:21px;width:289px;">SomnoSuite anesthesia system</td>
			<td style="width:129px;">Kent Scientific</td>
			<td style="width:101px;">SS-01</td>
			<td>Mouse anaesthetization for tMCAO</td>
		</tr>
		<tr height="21">
			<td height="21" style="height:21px;width:289px;">TCRb-BV510, clone H57-897</td>
			<td style="width:129px;">Biolegend</td>
			<td style="width:101px;">109234</td>
			<td>1:200 dilution</td>
		</tr>
		<tr height="21">
			<td height="21" style="height:21px;width:289px;">Zirconia/silica beads, 2.3 mm</td>
			<td style="width:129px;">Biospec</td>
			<td style="width:101px;">11079125z</td>
			<td>Beads for tissue homogenization</td>
		</tr>
	</tbody>
</table>

characterization of immune cells and proinflammatory mediators in the pulmonary environment

Immune cell expansion, activation, and trafficking to the lungs, which are controlled by the expression of multiple cytokines and chemokines, may be altered by severe brain injury. This is evidenced by the fact that pneumonia is a major cause of mortality in patients who have suffered from ischemic stroke. The goal of this protocol is to describe the use of multicolor flow cytometric analysis to identify 13 types of immune cells in the lungs of mice, including alveolar macrophages, interstitial macrophages, CD103+ or CD11b+ dendritic cells (DCs), plasmacytoid DCs, eosinophils, monocytes/monocyte-derived cells, neutrophils, lymphoid-derived&#160; T and B cells, NK cells, and NKT cells, following ischemic stroke induction by transient middle cerebral artery occlusion. Moreover, we describe the preparation of lung homogenates using a bead homogenization method, to determine the expression levels of 13 different cytokines or chemokines simultaneously by multiplex bead arrays coupled with flow cytometric analysis. This protocol can also be used to investigate the pulmonary immune response in other disease settings, such as infectious lung disease or allergic disease.

We recently reported that ischemic stroke induction in mice alters the immune cell composition of the lungs11. Specifically, transient cerebral ischemia increased percentages of alveolar macrophages, neutrophils, and CD11b+ DCs, while diminishing percentages of CD4+ T cells, CD8+ T cells, B cells, NK cells, and eosinophils in the pulmonary compartment. Moreover, cellular alteration corresponded to significantly diminished levels of multiple chemokines in the lungs. Described here is a method for t...

Watch this Scientific Journal Video about Characterization of Immune Cells and Proinflammatory Mediators in the Pulmonary Environment at JoVE.com

Characterization of Immune Cells and Proinflammatory Mediators in the Pulmonary Environment

This protocol describes the use of flow cytometry to identify the changes in immune cell composition, cytokine profile, and chemokine profile in the pulmonary environment following transient middle cerebral artery occlusion, a murine model of ischemic stroke.

Immune cell expansion, activation, and trafficking to the lungs, which are controlled by the expression of multiple cytokines and chemokines, may be ...

This protocol can be used to investigate alterations in the pulmonary environment following ischemic stroke. This method allows for the identification of 13 lung immune cell types and 13 different cytokines and chemokines in the same mouse via flow cytometric analysis. This method has been utilized to assess alterations in the pulmonary environment following ischemic stroke.However, it can also serve to investigate changes during allergic response or infection. To perform whole body transcardial perfusion, confirm a lack of response to pedal reflect in an anesthetized mouse and secure the mouse to a surgical platform. Wet the fur with 70%ethanol to reduce fur distribution into the body cavity and make a vertical midline skin incision to expose the intact peritoneum stopping the incision as soon as the thoracic cavity has been reached.Use fine dissection scissors to make a midline incision of the peritoneum stopping at the thoracic cavity prior and use forceps to grasp the distal end of the sternum. Use the scissors to cut through the diaphragm without damaging the heart, lungs, or vasculature. When the underlying tissues are visible, make an incision through the rib cage and secure the sides of the ribs so that the heart and lungs are fully exposed.Carefully make a small incision in the right atrium near the aortic arch to serve as the outflow for the perfusion and quickly but gently insert a 25 gauge needle into the distal superior surface of the left ventricle. Once the needle is in place gently flush 10 milliliters of cold PBS into the heart. The tissue should begin to clear of blood.When the entire volume has been delivered, perfuse a second 10 milliliter aliquot of cold PBS until the liver exhibits a light brown appearance and the lungs have transitioned from a reddish pink to a mostly white in color. Using forceps and fine dissection scissors, carefully remove all of the surrounding tissues before separating the lung lobes and placing them into a Petri dish containing one to two milliliters of cold lung cell, medium on ice. To prepare the lung tissue for multiplex bead arrays add 200 microliters of cold homogenization buffer to a two milliliter tube containing three sterile 2.3 milliliters Zirconia/Silica beads, and weigh the lung lobe of interest.Transfer 50 to 100 milligrams of lung tissue to the pre-chilled tube of beads and homogenization buffer and homogenize the lobe using a bead based homogenizer at 4, 000 rotations per minute for at least two minutes. When the tissue has been completely homogenized, centrifuge the tube to sediment the tissue and transfer the super natant to a pre-chilled 1.5 milliliter micro tube on ice. For lung tissue dissociation carefully decant the lung cell medium from the remaining lung lobe and insert a 25 gauge needle into the tissue.Inject 200 to 250 microliter volumes of dissociation buffer into each lung lobe to inflate the lungs until each of the lobes have been injected two to three times. After a two minute incubation at room temperature use fine dissection scissors to mince the lungs into small pieces and transfer the tissue solution into 15 milliliter chronicle tube. Add six milliliters of additional dissociation buffer to the sample and vortex vigorously for one minute.Next, incubate the tissue pieces for 45 minutes at 37 degrees Celsius vortexing every seven to eight minutes. At the end of the incubation, vortex the sample vigorously for one minute and pass the sample through a 100 micron cell strainer to remove any residual undesired connective and interstitial tissue. Collect the tissue by centrifugation and resuspend to the pellet with five milliliters of cold lung medium.Centrifuge the sample again and resuspend the pellet in one milliliter of cold lung medium with gentle vortexing. Then, filter the cells through a 100 micron strainer before counting. To evaluate the immune cell populations within the isolated lung tissue, seed one to two times 10 to the sixth power cells antibody set into the appropriate number of wells with a 96 well round bottom plate and dispose the cells to the bottom of the plate by centrifugation.Add 25 microliters of the appropriate antibody cocktail in cold FACS buffer to each well and mix with gentle pipe petting. After 20 minutes, resuspend the cells in 100 microliters of cold FACS buffer per well and transfer the samples to individual five milliliter polystyrene round bottom tubes containing 150 microliters of additional FACS buffer per tube. Then, immediately analyze the samples on a flow cytometer according to standard flow cytometric analysis protocols.In this representative analysis, 13 different populations of immune cells were identified in the lungs using three sets of five to seven antibody combinations. Dead cells were excluded using a live dead stain and the different immune cell types were distinguished using the antibodies and markers listed in the table. Alveolar and interstitial macrophages, CD103 positive and CD11B positive dendritic cells and eosinophils were identified in set one.Pro-inflammatory monocytes and neutrophils were identified in set two and CD4 positive and CD8 positive T cells, B cells, plasmacytoid dendritic cells, NK cells, and NKT cells were identified in set three. The total number of viable cells percentage of CD45 positive cells and total number of CD45 positive cells obtained were similar between cell populations that were isolated as demonstrated and cell populations that were isolated using a commercially available tissue dissociator. In addition, the percentage of cell death among CD45 positive cells was less than 10%for both protocols, suggesting that the demonstrated protocol facilitates a high yield, high cell quality recovery without the aid of an automated tissue dissociator.Further, using a commercially available multiplex assay coupled with flow cytometric analysis allows the concentration of chemokine in each sample per milligram of tissue to be determined. The collagenase D concentration, incubation time and temperature used during the single cell isolation critically impacts the immune cell recovery.

characterization-immune-cells-proinflammatory-mediators-pulmonary

Research

JoVE Journal

Immunology and Infection

3.2K Görüntüleme.  West Virginia University. This protocol can be used to investigate alterations in the pulmonary environment following ischemic stroke. This method allows for the identification of 13 lung immune cell types and 13 different cytokines and chemokines in the same mouse via flow cytometric analysis. This method has been utilized to assess alterations in the pulmonary environment following ischemic stroke.However, it can also serve to investigate changes during allergic response or infection. To perform whole body tr...