This work is supported by grants from the Canadian Institutes of Health Research (178918), Fonds de recherche en sant&#233; du Qu&#233;bec &#8211; Vision Health Research Network.

NOTE: Male C57BL/6 mice (5&#8211;7 weeks old) are from Charles River Laboratories International, Inc. (St-Constant, Quebec, Canada.) and manipulated according to protocols approved by the CHU Sainte-Justine Animal Care Committee. Mouse bronchial tissue explants provide a good source of primary bronchial epithelial cells for investigating the proapoptotic effects of LMPs on epithelial cells. This protocol describes the in vitro generation of LMPs, as well as a method for detecting apoptotic epithelial cells on LMPs-treated bronchial tissue explants. This protocol consists of 3 sections.
1. LMPs Production and Characterization
NOTE: To prevent contamination, ensure that all materials used in this experiment are sterile or autoclaved. Perform all steps at RT in a biological safety cabinet under sterile condition, unless otherwise indicated.
1.1) Stimulation and Collection of MPs9
<ol>
	<li>Thaw an aliquot of 10 million CEM T cells in a 37 &#176;C water bath. Dilute in 10 ml pre-warmed serum-free hematopoietic medium such as X-VIVO, in a 15 ml sterile tube and centrifuge at 200 g x 5 min. Aspirate the supernatant and resuspend cells in 5 ml pre-warmed medium.</li>
	<li>Transfer cells into a T75 tissue culture flask (for suspension cells) with 15 ml pre-warmed hematopoietic medium such as X-VIVO and incubate for 4 days in a humidified incubator at 37 &#176;C with 5% CO2 .</li>
	<li>After 4 days, transfer all the culture medium and cells into a T175 tissue culture flask containing 100 ml fresh medium. Continue incubating the cells for about 72 hr under the same conditions until they have grown to a density of 2 million cells/ml.</li>
	<li>Evenly split cells between four T175 flasks each containing 150 ml fresh medium and continue cell culture until cells have grown (approximately 48 hr incubation) to a density of 2 million/ml.</li>
	<li>Collect cells from each flask by centrifugation at 200 x g for 5 min and resuspend 300&#160;x 106&#160;cells into a new T175 flask containing 150 ml fresh medium, to maintain the 2 million/ml cell density .</li>
	<li>Add actinomycin&#160;D (dissolved in DMSO at 2 mg/ml) to the medium at a final concentration of 0.5 &#181;g/ml and incubate for 24 hr.</li>
	<li>Transfer all the culture medium into 50 ml conical tubes and spin down the cells at 750 x g for 5 min. Transfer the supernatant into 50 ml conical tubes and centrifuge at 1,500 x g for 15 min to remove large cell fragments.</li>
	<li>Transfer the supernatant into a 250 ml bottle and ultracentrifuge at 12,000 x g for 50 min. Discard the supernatant and collect pellets.</li>
	<li>Wash LMPs-enriched pellets with 40 ml sterile PBS in a 50 ml tube by centrifugation at 12,000 x g for 50 min. Repeat this step twice.</li>
	<li>Collect the last wash supernatant; it will be used as vehicle control. Suspend the LMPs pellets in 1 ml of PBS and transfer into a 1.5 ml sterile microtube. Aliquot and store isolated LMPs at -80 &#176;C (to avoid multiple free-thaw cycles).</li>
</ol>
1.2) Characterization of MPs via FACS Analysis 4
<ol>
	<li>Prepare 2 samples of annexin buffer, 1 with and another without CaCl2: Hepes 10 mM, NaCl 140 mM, plus or minus 5 mM CaCl2.</li>
	<li>Filter annexin buffer and FACS flow sheath fluid using a 0.22 &#181;m filter to remove particles.</li>
	<li>Dilute 1 &#181;l of LMPs in 44 &#181;l of annexin buffer with 5 mM CaCl2 into a FACS tube. Prepare another tube with 1 &#181;l of LMPs in 44 &#181;l of annexin buffer without CaCl2 (negative control).</li>
	<li>Add 5 &#181;l of annexinV-Cy5 in each tube and mix well. Incubate for 15 min at RT in the dark. Stop the reaction by diluting the mix with 400 &#181;l of FACS flow sheath fluid in each tube.</li>
	<li>Add 10 &#181;l (200,000 beads) of 7 &#181;m counting beads suspension as an internal standard in each tube to obtain an absolute count.</li>
	<li>Establish gates of relative size (FSC-H, PMT E00, log scale) and relative granularity (SSC-H, PMT 325, log scale) dot plot on the flow cytometer using size-calibrated fluorescent beads of 1 &#181;m (gate 1) and counting beads gate at 7 &#181;m (gate 2).</li>
	<li>Analyze the LMPs sample on FSC-H /SSC-H plot using the established gates and FL-4 channel for annexin (PMT 765, log scale) dot plot, by acquiring a signal until 20,000 counting beads are reached in gate 2.</li>
	<li>Determine the positive annexinV events of LMPs in annexin buffer containing CaCl2, and then subtract the events of LMPs in annexin buffer without CaCl2 (negative control).</li>
	<li>Calculate the absolute number of MPs based on the following equation: 
	<img alt="Equation 1" fo:content-width="4in" src="/files/ftp_upload/52651/52651eq1.jpg" /></li>
</ol>
1.3) Determination of MP Protein Concentration (Bradford Assay)
<ol>
	<li>Prepare 5 serial dilutions of a protein standard from 1.25 to 20 &#181;g/ml. Pipette 800 &#181;l of each standard and sample solution into a clean test tube in duplicate. Add 200 &#181;l of Bradford dye reagent to each tube. Mix well, then incubate at RT for 5 min.</li>
	<li>Measure absorbance at 595 nm. Determine the protein concentration of LMPs using the linear regression of standard curve.</li>
</ol>
2. Bronchial Tissue Explants and LMPs Treatment
NOTE: Pay special attention to the sterile working environment, and aseptically prepare the solutions and medium used in following experiments. To prepare the Complete Healing Medium, add 1 ml of Tissue Healing Medium Supplements with Serum (thawed on ice) to 100 ml Tissue Healing Medium and mix well.
2.1) Preparation of Bronchial Tissue Explants
<ol>
	<li>Before culturing, scratch 6 areas of 1 cm2 each at the edge of the surface of each 100 mm tissue culture dish with a scalpel blade. Coat each scratched 100 mm tissue culture dish with 2 ml of the culture dish coating solution, and incubate the dish in a humidified CO2 incubator O/N at 37 &#176;C. Vacuum aspirate the surplus solution and fill the dish with 15 ml of Tissue Washing Medium.</li>
	<li>Euthanize C57BL/6 mice (5 to 7 weeks old) by CO2 inhalation according to protocols approved by the animal care ethics committee.</li>
	<li>Aseptically dissect lung tissue with scalpel, Dumont super fine tweezer, and surgical scissors. Carefully remove parenchyma and blood vessels. Place lung tissue into ice-cold Tissue Washing Medium for transport to the laboratory, if applicable.</li>
	<li>Further dissect bronchus submerged in the Tissue Washing Medium and separate the bronchus with a diameter of 1 to 2.5 mm from peripheral lung tissues. Slice bronchial tissues into ~5 mm thick bronchial rings with a scalpel.</li>
	<li>Use a scooping motion with the sterile curved microdissecting forceps to pick up the bronchial fragments and place them onto the scratched areas of the dishes.</li>
	<li>Remove the Tissue Washing Medium, and incubate the fragments at RT for ~5 min to allow them to adhere to the dishes.</li>
	<li>Add 10 ml of Complete Healing Medium to each dish and place them in a controlled atmosphere modular incubator chamber. Flush the chamber with high O2 gas mixture (70% O2, 25% N2 and 5% CO2,). Place the chamber in a benchtop orbital incubator and shake it at 37 &#176;C. Shake the chamber for 24 hr at 10 cycles per minute to allow the medium to flow intermittently over the fragments.</li>
	<li>After 24 hr incubation, observe the tissue explants under a phase-contrast inverted light microscope. Select bronchial explants with complete, fine hair movement and lively bronchial epithelium for subsequent LMPs treatment.</li>
</ol>
2.2) LMPs Treatment
<ol>
	<li>Prepare complete growth medium as follows: thaw growth medium supplements with serum and fibroblast inhibitor on ice. Add 1 ml of the growth medium supplements with serum and 200 &#956;l fibroblast inhibitor to 100 ml of growth medium; mix thoroughly. Warm the complete growth medium at 37 &#176;C for 10 min prior to use.</li>
	<li>Dilute isolated LMPs in a new sterile eppendorf tube with PBS to prepare a LMPs stock at a concentration of 800 &#181;g/ml.</li>
	<li>Add 0.5 ml of Complete Growth Medium to each well of a 12-well tissue culture plate.</li>
	<li>Transfer the selected bronchial explants with the curved microdissecting forceps from the previous protocol (section 2.1) to each well of the tissue culture plate.</li>
	<li>Label the culture plate appropriately to identify LMPs treatment wells and control wells. Add 25 &#181;l LMPs stock into each LMPs treatment well (for a final concentration of 40 &#956;g/ml) and 25 &#181;l control vehicle (see LMPs production) to the control wells.</li>
	<li>Continue the incubation in a controlled atmosphere modular incubator chamber at 37 &#176;C with gentle shaking.</li>
	<li>After 24 hr, wash explants 3 times with PBS and proceed to the next step (4% paraformaldehyde [PFA] fixation).</li>
</ol>
3. Histopathological Examination
3.1) Prepare the Following Solutions Before Proceeding to the Next Steps
<ol>
	<li>Prepare 1x PBS buffer by mixing 137 mM NaCl, 2.7 mM KCl, 10 mM Na2HPO4, 1.76 mM KH2PO4, pH 7.4.</li>
	<li>To prepare 4% PFA, dissolve 20 g of PFA in 400 ml of water, heated at 60 &#176;C with stirring; add a few drops of 10 M NaOH to clear the solution. Next add 1x PBS buffer and adjust the volume to 500 ml and pH to 7.4. Filter and aliquot; store at -20 &#176;C.</li>
	<li>Prepare the following dehydration or rehydration reagents; 100%, 90%, 70%, 50% ethanol and xylene.</li>
</ol>
3.2) Explant Fixation and Tissue Section Deparaffinization
<ol>
	<li>Place each explant in a labelled microcentrifuge tube with 1.5 ml of 4% PFA and incubate O/N at 4 &#176;C. Rinse the explants twice with 1x PBS.</li>
	<li>Dehydrate explants through an alcohol series (70% ethanol: 3 times 30 min each; 90% ethanol: 2 times 30 min each; 100% ethanol: 3 times 30 min each; then xylene: 3 times 20 min each). Perform all steps at RT in a fume hood.</li>
	<li>Imbed tissue explants in paraffin at 58 &#176;C in an oven. Prepare 5 &#181;m thick tissue sections using a rotary microtome.</li>
	<li>Float the sections in a 56 &#176;C water bath, and then mount the sections onto labeled histological slides. Place the slides in manual staining racks and dry at 65 &#176;C for 1 hr. Allow the slides to cool at RT.</li>
	<li>Dip the racks in 4 consecutive stain dishes containing xylene for 10 min each to remove paraffin. Dip the racks in an ethanol series to remove xylene: 100%, then 95%, then 80%, then 70%, then 50% ethanol (5 min for every step). Rinse the racks with tap water for 5 min to remove ethanol.</li>
</ol>
3.3) Hematoxylin and Eosin (H&#38;E) Staining&#160;
<ol>
	<li>Continue working with the fixed tissue sections; place the rack into a staining dish filled with Mayer&#39;s Hematoxylin for 15 min. Rinse the rack with tap water to remove Hematoxylin for 20 min.</li>
	<li>Place in distilled water for 30 sec.Place in 95% ethanol for 30 sec. Place in Eosin Y solution staining dish for 1 min. Dehydrate through 2 changes of 95% ethanol, 100% ethanol, and xylene for 2 min each.</li>
	<li>Perform a quick check under a microscope to ensure that excess eosin is removed. Place 2 to 3 drops of Mounting Medium (Fisher SP15-100) onto each slide, then cover with a cover glass.</li>
</ol>
3.4) In Situ Cell Death Detection: TUNEL Assay
<ol>
	<li>Before beginning, prepare proteinase K working solution: 20 &#181;g/ml in 10 mM Tris/HCl, pH 7.4.</li>
	<li>Repeat steps 1 to 5 of section 3.2 (Explant fixation and tissue section deparaffinization). Rinse the slides with deionized H2O.</li>
	<li>Immerse the slides with 1x PBS for 10 min. Drain the excess PBS. Incubate tissue sections for 30 min at RT&#160;with proteinase K working solution. Rinse slides twice with 1x PBS.</li>
	<li>Perform the TUNEL assay as described in the Instruction Manual of cell death detection kit. Mount using mounting medium, and coverslip manually with glass coverslips.</li>
	<li>Analyze samples under a light microscope. Use Image Pro 4.5 to analyze the apoptotic cells in brown color.</li>
</ol>

<ol>
	<li>Tushuizen, M. E., Diamant, M., Sturk, A., Nieuwland, R. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Cell-derived+microparticles+in+the+pathogenesis+of+cardiovascular+disease:+friend+or+foe.">Cell-derived microparticles in the pathogenesis of cardiovascular disease: friend or foe.</a> Arterioscler Thromb Vasc Biol. 31 (1), 4-9 (2011).</li><li>Martinez, M. C., Tual-Chalot, S., Leonetti, D., Andriantsitohaina, R. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Microparticles:+targets+and+tools+in+cardiovascular+disease.">Microparticles: targets and tools in cardiovascular disease.</a> Trends Pharmacol Sci. 32 (11), 659-665 (2011).</li><li>Benameur, T., Andriantsitohaina, R., Martinez, M. C. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Therapeutic+potential+of+plasma+membrane-derived+microparticles.">Therapeutic potential of plasma membrane-derived microparticles.</a> Pharmacol Rep. 61 (1), 49-57 (2009).</li><li>Yang, 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=Lymphocytic+microparticles+inhibit+angiogenesis+by+stimulating+oxidative+stress+and+negatively+regulating+VEGF-induced+pathways.">Lymphocytic microparticles inhibit angiogenesis by stimulating oxidative stress and negatively regulating VEGF-induced pathways.</a> Am J Physiol Regul Integr Comp Physiol. 294 (2), 467-476 (2008).</li><li>Yang, C., Gagnon, C., Hou, X., Hardy, P. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Low+density+lipoprotein+receptor+mediates+anti-VEGF+effect+of+lymphocyte+T-derived+microparticles+in+Lewis+lung+carcinoma+cells.">Low density lipoprotein receptor mediates anti-VEGF effect of lymphocyte T-derived microparticles in Lewis lung carcinoma cells.</a> Cancer Biol Ther. 10 (5), 448-456 (2010).</li><li>Angelillo-Scherrer, A. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Leukocyte-derived+microparticles+in+vascular+homeostasis.">Leukocyte-derived microparticles in vascular homeostasis.</a> Circ Res. 110 (2), 356-369 (2012).</li><li>Maeno, 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=CD8++T+Cells+are+required+for+inflammation+and+destruction+in+cigarette+smoke-induced+emphysema+in+mice.">CD8+ T Cells are required for inflammation and destruction in cigarette smoke-induced emphysema in mice.</a> J Immunol. 178 (12), 8090-8096 (2007).</li><li>Qiu, Q., Xiong, W., Yang, C., Gagnon, C., Hardy, P. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Lymphocyte-derived+microparticles+induce+bronchial+epithelial+cells'+pro-inflammatory+cytokine+production+and+apoptosis.">Lymphocyte-derived microparticles induce bronchial epithelial cells' pro-inflammatory cytokine production and apoptosis.</a> Mol Immunol. 55 (3-4), 220-230 (2013).</li><li>Martin, S., 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=Shed+membrane+particles+from+T+lymphocytes+impair+endothelial+function+and+regulate+endothelial+protein+expression.">Shed membrane particles from T lymphocytes impair endothelial function and regulate endothelial protein expression.</a> Circulation. 109 (13), 1653-1659 (2004).</li><li>Shet, A. 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F., Weber, C. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Microparticles:+protagonists+of+a+novel+communication+network+for+intercellular+information+exchange.">Microparticles: protagonists of a novel communication network for intercellular information exchange.</a> Circ Res. 107 (9), 1047-1057 (2010).</li><li>Yang, 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=Anti-proliferative+and+anti-tumour+effects+of+lymphocyte-derived+microparticles+are+neither+species-+nor+tumour-type+specific.">Anti-proliferative and anti-tumour effects of lymphocyte-derived microparticles are neither species- nor tumour-type specific.</a> J Extracell Vesicles. 3, (2014).</li><li>Soleti, R., 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=Microparticles+harboring+Sonic+Hedgehog+promote+angiogenesis+through+the+upregulation+of+adhesion+proteins+and+proangiogenic+factors.">Microparticles harboring Sonic Hedgehog promote angiogenesis through the upregulation of adhesion proteins and proangiogenic factors.</a> Carcinogenesis. 30 (4), 580-588 (2009).</li></ol>

The authors have nothing to disclose.

MPs are active mediators of intercellular cross talk and their study is promising in many areas of science.11 This study presented a detailed protocol for in vitro large-scale generation of LMPs derived from an apoptotic T cell line. These MPs express a large repertoire of lymphocyte molecules and are biologically implicated in the regulation of cellular and tissue homeostasis. However, LMPs derived from different sources may be biologically different.4,9,12,13
L...

Microparticles (MPs) are biologically active submicron membrane vesicles released following cell activation or apoptosis. MPs are derived from both healthy and damaged cells and are implicated in many physiological and pathological processes.1 MPs have been detected not only in human plasma, but also in inflammatory and apoptotic tissue. The biological utility of cell membrane&#8211;derived MPs has been demonstrated in various settings, including cell signalling models and as pharmacological tools.2,3 We previously demonstrated that LMPs derived from T lymphocytes following actinomycin D stimulation (to induce apoptosis) suppress angiogenesis and inhibit endothelial cell survival and proliferation.4,5 The antiangiogenic effects of LMPs may vary significantly depending on the stimuli used to activate T lymphocytes in vitro.6
The airway epithelium functions as a protective physical and functional barrier. Increased numbers of T lymphocytes in the airway can contribute to cell damage and airway inflammation.7 We have shown that LMPs induce apoptosis of human bronchial epithelial cells,8 which indicated LMPs may change barrier function of bronchial epithelium in vivo. Apoptotic cells can be identified using the TUNEL method, which detects in situ DNA fragmentation. 
The overall goal of this protocol is to illustrate the in vitro production of LMPs from a T lymphocyte cell line, and to demonstrate their proapoptotic effect on airway epithelial cells. In situ cell death detection demonstrated that LMPs strongly induce airway bronchial epithelial cell death, suggesting that LMPs-mediated injury to the airway epithelium may impact barrier function of the damaged epithelium.

<table border="0" cellpadding="0" cellspacing="0" width="828">
	<tbody>
		<tr height="21">
			<td height="21" style="height:21px;width:303px;">LMPs production and characterization</td>
			<td style="width:231px;"></td>
			<td style="width:124px;"></td>
			<td style="width:171px;"></td>
		</tr>
		<tr height="21">
			<td height="21" style="height:21px;">CEM T cells&#160;</td>
			<td style="width:231px;">ATCC&#160;</td>
			<td style="width:124px;">CCL-119</td>
			<td></td>
		</tr>
		<tr height="21">
			<td height="21" style="height:21px;width:303px;">X-VIVO 15 medium&#160;</td>
			<td style="width:231px;">Cambrex, Walkersville</td>
			<td>04-744Q</td>
			<td></td>
		</tr>
		<tr height="21">
			<td height="21" style="height:21px;width:303px;">Flask T75</td>
			<td style="width:231px;">Sarstedt</td>
			<td style="width:124px;">83.1813.502</td>
			<td></td>
		</tr>
		<tr height="21">
			<td height="21" style="height:21px;width:303px;">Flask T175</td>
			<td style="width:231px;">Sarstedt</td>
			<td style="width:124px;">83.1812.502</td>
			<td></td>
		</tr>
		<tr height="21">
			<td height="21" style="height:21px;">Actinomycin&#160;D&#160;</td>
			<td style="width:231px;">Sigma Chemical Co.</td>
			<td style="width:124px;">A9415-2mg</td>
			<td></td>
		</tr>
		<tr height="21">
			<td height="21" style="height:21px;width:303px;">PBS</td>
			<td style="width:231px;">Lifetechnologies</td>
			<td>14190-144</td>
			<td></td>
		</tr>
		<tr height="21">
			<td height="21" style="height:21px;">0.22&#181;m filter</td>
			<td style="width:231px;">Sarstedt</td>
			<td style="width:124px;">83.1826.001</td>
			<td></td>
		</tr>
		<tr height="21">
			<td height="21" style="height:21px;width:303px;">Annexin-VCy5</td>
			<td style="width:231px;">BD Pharmagen&#160;</td>
			<td>559933</td>
			<td></td>
		</tr>
		<tr height="21">
			<td height="21" style="height:21px;">FACS flow solution</td>
			<td>BD Bio-sciences</td>
			<td style="width:124px;">342003</td>
			<td></td>
		</tr>
		<tr height="21">
			<td height="21" style="height:21px;width:303px;">Fluorescent microbeads (1 um)</td>
			<td style="width:231px;">Molecular Probes&#160;</td>
			<td style="width:124px;">T8880</td>
			<td></td>
		</tr>
		<tr height="21">
			<td height="21" style="height:21px;">Polysterene counting beads (7 um)</td>
			<td style="width:231px;">Bangs laboratories</td>
			<td style="width:124px;">PS06N/6994</td>
			<td></td>
		</tr>
		<tr height="21">
			<td height="21" style="height:21px;">Polypropylene FACS tubes</td>
			<td>Falcon</td>
			<td style="width:124px;">352058</td>
			<td></td>
		</tr>
		<tr height="21">
			<td height="21" style="height:21px;width:303px;">1 ml pipet</td>
			<td style="width:231px;">Fisher</td>
			<td style="width:124px;">13-678-11B</td>
			<td></td>
		</tr>
		<tr height="21">
			<td height="21" style="height:21px;width:303px;">5 ml pipet</td>
			<td style="width:231px;">Falcon</td>
			<td style="width:124px;">357543</td>
			<td></td>
		</tr>
		<tr height="21">
			<td height="21" style="height:21px;width:303px;">25 ml pipet</td>
			<td style="width:231px;">Ultident</td>
			<td style="width:124px;">DL-357551</td>
			<td></td>
		</tr>
		<tr height="21">
			<td height="21" style="height:21px;width:303px;">1,5 ml conical polypropylene micro tube</td>
			<td style="width:231px;">Sarstedt</td>
			<td style="width:124px;">72.690</td>
			<td></td>
		</tr>
		<tr height="21">
			<td height="21" style="height:21px;width:303px;">15 ml conical polypropylene tube</td>
			<td style="width:231px;">Sarstedt</td>
			<td style="width:124px;">62.554.205</td>
			<td></td>
		</tr>
		<tr height="21">
			<td height="21" style="height:21px;width:303px;">50 ml conical polypropylene tube</td>
			<td style="width:231px;">Sarstedt</td>
			<td style="width:124px;">62.547.205</td>
			<td></td>
		</tr>
		<tr height="42">
			<td height="42" style="height:42px;width:303px;">50 ml high speed polypropylene copolymer tube</td>
			<td style="width:231px;">Nalgene</td>
			<td style="width:124px;">3119-0050</td>
			<td></td>
		</tr>
		<tr height="21">
			<td height="21" style="height:21px;width:303px;">250 ml high speed polypropylene bottle</td>
			<td style="width:231px;">Beckman</td>
			<td style="width:124px;">356011</td>
			<td></td>
		</tr>
		<tr height="21">
			<td height="21" style="height:21px;">Protein assay (Bradford assay)</td>
			<td>Bio-Rad Laboratories</td>
			<td>500-0006</td>
			<td></td>
		</tr>
		<tr height="21">
			<td height="21" style="height:21px;">Protein assay standard II</td>
			<td>Bio-Rad Laboratories</td>
			<td>500-0007</td>
			<td></td>
		</tr>
		<tr height="21">
			<td height="21" style="height:21px;">Test tube 16x100</td>
			<td>VWR</td>
			<td>47729-576</td>
			<td></td>
		</tr>
		<tr height="21">
			<td height="21" style="height:21px;">Test tube 12x75</td>
			<td>Ultident</td>
			<td>170-14100005B</td>
			<td></td>
		</tr>
		<tr height="21">
			<td height="21" style="height:21px;">Cell incubator&#160;</td>
			<td style="width:231px;">Mandel</td>
			<td style="width:124px;">Heracell 150</td>
			<td></td>
		</tr>
		<tr height="21">
			<td height="21" style="height:21px;width:303px;">Low speed centrifuge</td>
			<td style="width:231px;">IEC</td>
			<td style="width:124px;">Centra8R</td>
			<td></td>
		</tr>
		<tr height="21">
			<td height="21" style="height:21px;width:303px;">High speed centrifuge</td>
			<td style="width:231px;">Beckman</td>
			<td style="width:124px;">Avanti J8</td>
			<td></td>
		</tr>
		<tr height="21">
			<td height="21" style="height:21px;width:303px;">High speed rotor for 250ml bottle</td>
			<td style="width:231px;">Beckman</td>
			<td style="width:124px;">JLA16.250</td>
			<td></td>
		</tr>
		<tr height="21">
			<td height="21" style="height:21px;width:303px;">High speed rotor for 50ml tube</td>
			<td style="width:231px;">Beckman</td>
			<td style="width:124px;">JA30.50</td>
			<td></td>
		</tr>
		<tr height="21">
			<td height="21" style="height:21px;">Fow cytometry&#160;</td>
			<td>BD Bio-sciences</td>
			<td style="width:124px;">FACS Calibur</td>
			<td></td>
		</tr>
		<tr height="21">
			<td height="21" style="height:21px;width:303px;">Spectrophotometer</td>
			<td style="width:231px;">Beckman</td>
			<td style="width:124px;">Series 600</td>
			<td></td>
		</tr>
		<tr height="21">
			<td height="21" style="height:21px;width:303px;"></td>
			<td style="width:231px;"></td>
			<td style="width:124px;"></td>
			<td></td>
		</tr>
		<tr height="21">
			<td height="21" style="height:21px;">Bronchial tissue explants and sections&#160;</td>
			<td style="width:231px;"></td>
			<td style="width:124px;"></td>
			<td></td>
		</tr>
		<tr height="21">
			<td height="21" style="height:21px;">C57BL/6 mice (5-7 weeks old)&#160;&#160;</td>
			<td style="width:231px;">Charles River Laboratories, Inc.&#160;</td>
			<td style="width:124px;"></td>
			<td></td>
		</tr>
		<tr height="21">
			<td height="21" style="height:21px;">Mouse Airway PrimaCell&#8482; System:</td>
			<td style="width:231px;">CHI Scientific, Inc.</td>
			<td style="width:124px;">2-82001</td>
			<td></td>
		</tr>
		<tr height="21">
			<td height="21" style="height:21px;">&#160;Rib-Back Carbon Steel Scalpel Blades</td>
			<td style="width:231px;">Becton Dickinson AcuteCare</td>
			<td style="width:124px;">371310</td>
			<td>#10</td>
		</tr>
		<tr height="21">
			<td height="21" style="height:21px;">Scalpel Handle</td>
			<td style="width:231px;">Fine Science Tools Inc.&#160;</td>
			<td style="width:124px;">10003-12</td>
			<td>#7</td>
		</tr>
		<tr height="21">
			<td height="21" style="height:21px;">phase-contrast inverted microscope</td>
			<td style="width:231px;">Olympus Optical CO., LTD.&#160;&#160;&#160;</td>
			<td style="width:124px;">CK2</td>
			<td></td>
		</tr>
		<tr height="25">
			<td height="25" style="height:25px;">high O2 gas mixture&#160;</td>
			<td>VitalAire Canada Inc.</td>
			<td style="width:124px;"></td>
			<td></td>
		</tr>
		<tr height="21">
			<td height="21" style="height:21px;width:303px;">modular incubator chamber</td>
			<td style="width:231px;">Billups-Rothenberg Inc.</td>
			<td style="width:124px;">MIC-101</td>
			<td></td>
		</tr>
		<tr height="21">
			<td height="21" style="height:21px;">MaxQ 4000 incubated orbital shaker</td>
			<td style="width:231px;">Barnstead Lab-Line,&#160;</td>
			<td style="width:124px;">SHKA4000-7</td>
			<td></td>
		</tr>
		<tr height="21">
			<td height="21" style="height:21px;">12-well tissue culture plate</td>
			<td style="width:231px;">Becton Dickinson and Company</td>
			<td style="width:124px;">353043</td>
			<td></td>
		</tr>
		<tr height="21">
			<td height="21" style="height:21px;width:303px;">Plastic tissue culture dishes (100 mm)</td>
			<td style="width:231px;">Sarstedt, Inc.</td>
			<td style="width:124px;">83.1802</td>
			<td></td>
		</tr>
		<tr height="42">
			<td height="42" style="height:42px;width:303px;">Surgical scissors</td>
			<td style="width:231px;">Fine Science Tools Inc.&#160;</td>
			<td style="width:124px;">14060-09</td>
			<td style="width:171px;">Straight, sharp, 9cm longth</td>
		</tr>
		<tr height="21">
			<td height="21" style="height:21px;width:303px;">Half-curved Graefe forceps</td>
			<td style="width:231px;">Fine Science Tools Inc.&#160;</td>
			<td style="width:124px;">11052-10</td>
			<td></td>
		</tr>
		<tr height="21">
			<td height="21" style="height:21px;width:303px;">humidified CO2 incubator</td>
			<td style="width:231px;">Mandel Scientific Company Inc.&#160;</td>
			<td style="width:124px;">SVH-51023421</td>
			<td></td>
		</tr>
		<tr height="21">
			<td height="21" style="height:21px;width:303px;"></td>
			<td style="width:231px;"></td>
			<td style="width:124px;"></td>
			<td></td>
		</tr>
		<tr height="21">
			<td height="21" style="height:21px;">&#160;Histopathological examination&#160;</td>
			<td style="width:231px;"></td>
			<td style="width:124px;"></td>
			<td></td>
		</tr>
		<tr height="21">
			<td height="21" style="height:21px;">formalin formaldehyde</td>
			<td style="width:231px;">Sigma-Aldrich, Inc.&#160;</td>
			<td style="width:124px;">HT5011</td>
			<td></td>
		</tr>
		<tr height="21">
			<td height="21" style="height:21px;">paraffin</td>
			<td style="width:231px;">Fisher scientific&#160; International, Inc.</td>
			<td style="width:124px;">T555</td>
			<td></td>
		</tr>
		<tr height="21">
			<td height="21" style="height:21px;">ethyl alcohol</td>
			<td style="width:231px;">Merck KGaA, Darmstadt</td>
			<td style="width:124px;">EX0278-1</td>
			<td></td>
		</tr>
		<tr height="21">
			<td height="21" style="height:21px;">&#160;glutaraldehyde&#160;</td>
			<td style="width:231px;">Sigma-Aldrich, Inc.&#160;</td>
			<td style="width:124px;">G6403</td>
			<td></td>
		</tr>
		<tr height="21">
			<td height="21" style="height:21px;">Cacodylate</td>
			<td style="width:231px;">Sigma-Aldrich, Inc.&#160;</td>
			<td style="width:124px;">31533</td>
			<td></td>
		</tr>
		<tr height="21">
			<td height="21" style="height:21px;">microscope slides</td>
			<td style="width:231px;">VWR Scientific Inc.&#160;</td>
			<td style="width:124px;">48300-025</td>
			<td>25x75mm</td>
		</tr>
		<tr height="21">
			<td height="21" style="height:21px;">Xylene</td>
			<td style="width:231px;">Fisher scientific&#160; International, Inc.</td>
			<td style="width:124px;">X5-4</td>
			<td></td>
		</tr>
		<tr height="21">
			<td height="21" style="height:21px;">Mayer&#39;s hematoxylin</td>
			<td style="width:231px;">Sigma-Aldrich, Inc.&#160;</td>
			<td style="width:124px;">MHS16</td>
			<td>Funnel with filter paper&#160;&#160;</td>
		</tr>
		<tr height="21">
			<td height="21" style="height:21px;">HCl&#160;</td>
			<td style="width:231px;">Fisher scientific&#160; International, Inc.&#160;&#160;</td>
			<td style="width:124px;">A144s-500</td>
			<td></td>
		</tr>
		<tr height="21">
			<td height="21" style="height:21px;">eosin&#160;</td>
			<td style="width:231px;">Sigma-Aldrich, Inc.&#160;</td>
			<td style="width:124px;">HT110116</td>
			<td>Funnel with filter paper&#160;&#160;</td>
		</tr>
		<tr height="21">
			<td height="21" style="height:21px;">Permount&#8482; Mounting Medium</td>
			<td style="width:231px;">Thermo Fisher Scientific Inc.&#160;</td>
			<td>SP15-100</td>
			<td></td>
		</tr>
		<tr height="21">
			<td height="21" style="height:21px;">glass coverslip</td>
			<td style="width:231px;">surgipath medical industries, Inc.</td>
			<td style="width:124px;">84503</td>
			<td>24&#215;24&#160;#1&#160;</td>
		</tr>
		<tr height="21">
			<td height="21" style="height:21px;">TUNEL detection kit</td>
			<td style="width:231px;">In Situ Cell Death Detection, POD</td>
			<td style="width:124px;">11 684 817 910</td>
			<td></td>
		</tr>
		<tr height="21">
			<td height="21" style="height:21px;">oven</td>
			<td style="width:231px;">Despatch Industries Inc.</td>
			<td style="width:124px;">LEB-1-20</td>
			<td></td>
		</tr>
		<tr height="21">
			<td height="21" style="height:21px;width:303px;">rotary Microtome</td>
			<td style="width:231px;">Leica Microsystems Inc.</td>
			<td style="width:124px;">RM2145</td>
			<td></td>
		</tr>
		<tr height="21">
			<td height="21" style="height:21px;width:303px;">filter paper</td>
			<td style="width:231px;">Whatman International Ltd.</td>
			<td style="width:124px;">1003150</td>
			<td>#3</td>
		</tr>
		<tr height="21">
			<td height="21" style="height:21px;">Microscope</td>
			<td style="width:231px;">Nikon Imaging Japan Inc.</td>
			<td style="width:124px;">E800</td>
			<td></td>
		</tr>
		<tr height="21">
			<td height="21" style="height:21px;">staining dish complete</td>
			<td style="width:231px;">Wheaton Industries, Inc.</td>
			<td>900200</td>
			<td>including dish, rack, cover</td>
		</tr>
		<tr height="21">
			<td height="21" style="height:21px;width:303px;">1.5 ml eppendorf tube</td>
			<td style="width:231px;">Sarstedt Inc.&#160;</td>
			<td style="width:124px;">72.69</td>
			<td>39x10mm</td>
		</tr>
		<tr height="21">
			<td height="21" style="height:21px;">Orbital and Reciprocating Water Bath</td>
			<td style="width:231px;">ExpotechUSA</td>
			<td style="width:124px;">ORS200</td>
			<td></td>
		</tr>
		<tr height="21">
			<td height="21" style="height:21px;">phosphate buffered saline&#160;&#160;</td>
			<td style="width:231px;">GIBCO</td>
			<td style="width:124px;">14190-144</td>
			<td></td>
		</tr>
		<tr height="21">
			<td height="21" style="height:21px;">fume hood</td>
			<td>Nicram RD Service</td>
			<td>3707E</td>
			<td></td>
		</tr>
	</tbody>
</table>

generation of lymphocytic microparticles and detection of their proapoptotic effect on airway epithelial cells

Interest in the biological roles of cell membrane&#8211;derived vesicles in cell&#8211;cell communication has increased in recent years. Microparticles (MPs) are one such type of vesicles, ranging in diameter from 0.1 &#956;m to 1 &#956;m, and typically shed from the plasma membrane of eukaryotic cells undergoing activation or apoptosis. Here we describe the generation of T lymphocyte&#8211;derived microparticles (LMPs) from apoptotic CEM T cells stimulated with actinomycin D. LMPs are isolated through a multistep differential centrifugation process and characterized using flow cytometry. This protocol also presents an in situ cell death detection method for demonstrating the proapoptotic effect of LMPs on bronchial epithelial cells derived from mouse primary respiratory bronchial tissue explants. Methods described herein provide a reproducible procedure for isolating abundant quantities of LMPs from apoptotic lymphocytes in vitro. LMPs derived in this manner can be used to evaluate the characteristics of various disease models, and for pharmacology and toxicology testing. Given that the airway epithelium offers a protective physical and functional barrier between the external environment and underlying tissue, use of bronchial tissue explants rather than immortalized epithelial cell lines provides an effective model for investigations requiring airway tract tissue.

LMPs were characterized with annexin V staining10 by fluorescence-activated cell sorting (FACS) analysis and gated using 1 &#181;m beads in which 97% of MPs (&#8804;1 &#181;m) were annexin-V-Cy5 positive (Figure 1A and 1B). Typically, about 2.5 mg of LMPs were obtained following this protocol. Bronchial tissue explants from C57BL/6 mice were subjected to vehicle and LMPs treatment. Histopathological analysis of bronchial sections revealed the effect of LMPs on the structural integrity of the b...

Watch this Scientific Journal Video about Generation of Lymphocytic Microparticles and Detection of their Proapoptotic Effect on Airway Epithelial Cells at JoVE.com

Generation of Lymphocytic Microparticles and Detection of their Proapoptotic Effect on Airway Epithelial Cells

Cell membrane&#8211;shed microparticles (MPs) are active biological vesicles that can be isolated and their pathophysiological effects investigated in various models. Here we describe a method for generating MPs derived from T lymphocytes (LMPs) and for demonstrating their proapoptotic effect on airway epithelial cells.

Interest in the biological roles of cell membrane&#8211;derived vesicles in cell&#8211;cell communication has increased in recent years. Microparticles ...

generation-lymphocytic-microparticles-detection-their-proapoptotic

Research

JoVE Journal

Immunology and Infection

8.9K Views.  University of Montréal. Cell membrane–shed microparticles (MPs) are active biological vesicles that can be isolated and their pathophysiological effects investigated in various models. Here we describe a method for generating MPs derived from T lymphocytes (LMPs) and for demonstrating their proapoptotic effect on airway epithelial cells.

Video: Generation of Lymphocytic Microparticles and Detection of their Proapoptotic Effect on Airway Epithelial Cells

Co-culture Models of Pseudomonas aeruginosa Biofilms Grown on Live Human Airway Cells

Bacterial biofilms have been associated with a number of different human diseases, but biofilm development has generally been studied on non-living surfaces. In this paper, we describe protocols for forming Pseudomonas aeruginosa biofilms on human airway epithelial cells (CFBE cells) grown in culture. In the first method (termed the Static Co-culture Biofilm Model), P. aeruginosa is incubated with CFBE cells grown as confluent monolayers on standard tissue culture plates. Although the bacterium is quite toxic to epithelial cells, the addition of arginine delays the destruction of the monolayer long enough for biofilms to form on the CFBE cells. The second method (termed the Flow Cell Co-culture Biofilm Model), involves adaptation of a biofilm flow cell apparatus, which is often used in biofilm research, to accommodate a glass coverslip supporting a confluent monolayer of CFBE cells. This monolayer is inoculated with P. aeruginosa and a peristaltic pump then flows fresh medium across the cells. In both systems, bacterial biofilms form within 6-8 hours after inoculation. Visualization of the biofilm is enhanced by the use of P. aeruginosa strains constitutively expressing green fluorescent protein (GFP). The Static and Flow Cell Co-culture Biofilm assays are model systems for early P. aeruginosa infection of the Cystic Fibrosis (CF) lung, and these techniques allow different aspects of P. aeruginosa biofilm formation and virulence to be studied, including biofilm cytotoxicity, measurement of biofilm CFU, and staining and visualizing the biofilm.

Co-culture Models of Pseudomonas aeruginosa Biofilms Grown on Live Human Airway Cells

This paper describes different methods of growing Pseudomonas aeruginosa biofilms on cultured human airway epithelial cells. These protocols can be adapted to study different aspects of biofilm formation, including visualization of the biofilm, staining of the biofilm, measuring the colony forming units (CFU) of the biofilm, and studying biofilm cytotoxicity.

Bacterial biofilms have been associated with a number of different human diseases, but biofilm development has generally been studied on non-living ...

Combination of Adhesive-tape-based Sampling and Fluorescence in situ Hybridization for Rapid Detection of Salmonella on Fresh Produce

This protocol describes a simple approach for adhesive-tape-based sampling of tomato and other fresh produce surfaces, followed by on-tape fluorescence in situ hybridization (FISH) for rapid culture-independent detection of Salmonella spp. Cell-charged tapes can also be placed face-down on selective agar for solid-phase enrichment prior to detection. Alternatively, low-volume liquid enrichments (liquid surface miniculture) can be performed on the surface of the tape in non-selective broth, followed by FISH and analysis via flow cytometry. To begin, sterile adhesive tape is brought into contact with fresh produce, gentle pressure is applied, and the tape is removed, physically extracting microbes present on these surfaces. Tapes are mounted sticky-side up onto glass microscope slides and the sampled cells are fixed with 10% formalin (30 min) and dehydrated using a graded ethanol series (50, 80, and 95%; 3 min each concentration). Next, cell-charged tapes are spotted with buffer containing a Salmonella-targeted DNA probe cocktail and hybridized for 15 - 30 min at 55&deg;C, followed by a brief rinse in a washing buffer to remove unbound probe. Adherent, FISH-labeled cells are then counterstained with the DNA dye 4',6-diamidino-2-phenylindole (DAPI) and results are viewed using fluorescence microscopy. For solid-phase enrichment, cell-charged tapes are placed face-down on a suitable selective agar surface and incubated to allow in situ growth of Salmonella microcolonies, followed by FISH and microscopy as described above. For liquid surface miniculture, cell-charged tapes are placed sticky side up and a silicone perfusion chamber is applied so that the tape and microscope slide form the bottom of a water-tight chamber into which a small volume (&le; 500 &mu;L) of Trypticase Soy Broth (TSB) is introduced. The inlet ports are sealed and the chambers are incubated at 35 - 37&deg;C, allowing growth-based amplification of tape-extracted microbes. Following incubation, inlet ports are unsealed, cells are detached and mixed with vigorous back and forth pipetting, harvested via centrifugation and fixed in 10% neutral buffered formalin. Finally, samples are hybridized and examined via flow cytometry to reveal the presence of Salmonella spp. As described here, our "tape-FISH" approach can provide simple and rapid sampling and detection of Salmonella on tomato surfaces. We have also used this approach for sampling other types of fresh produce, including spinach and jalape&ntilde;o peppers.

Combination of Adhesive-tape-based Sampling and Fluorescence in situ Hybridization for Rapid Detection of Salmonella on Fresh Produce

This protocol describes a simple adhesive-tape-based approach for sampling of tomato and other fresh produce surfaces, followed by rapid whole cell detection of Salmonella using fluorescence in situ hybridization (FISH).

This protocol describes a simple approach for adhesive-tape-based sampling of tomato and other fresh produce surfaces, followed by on-tape fluorescence in ...

Application of a Mouse Ligated Peyer&#x2019;s Patch Intestinal Loop Assay to Evaluate Bacterial Uptake by M cells

The inside of our gut is inhabited with enormous number of commensal bacteria. The mucosal surface of the gastrointestinal tract is continuously exposed to them and occasionally to pathogens. The gut-associated lymphoid tissue (GALT) play a key role for induction of the mucosal immune response to these microbes1, 2. To initiate the mucosal immune response, the mucosal antigens must be transported from the gut lumen across the epithelial barrier into organized lymphoid follicles such as Peyer's patches. This antigen transcytosis is mediated by specialized epithelial M cells3, 4. M cells are atypical epithelial cells that actively phagocytose macromolecules and microbes. Unlike dendritic cells (DCs) and macrophages, which target antigens to lysosomes for degradation, M cells mainly transcytose the internalized antigens. This vigorous macromolecular transcytosis through M cells delivers antigen to the underlying organized lymphoid follicles and is believed to be essential for initiating antigen-specific mucosal immune responses. However, the molecular mechanisms promoting this antigen uptake by M cells are largely unknown. We have previously reported that glycoprotein 2 (Gp2), specifically expressed on the apical plasma membrane of M cells among enterocytes, serves as a transcytotic receptor for a subset of commensal and pathogenic enterobacteria, including Escherichia coli and Salmonella enterica serovar Typhimurium (S. Typhimurium), by recognizing FimH, a component of type I pili on the bacterial outer membrane 5. Here, we present a method for the application of a mouse Peyer's patch intestinal loop assay to evaluate bacterial uptake by M cells. This method is an improved version of the mouse intestinal loop assay previously described 6, 7. The improved points are as follows: 1. Isoflurane was used as an anesthetic agent. 2. Approximately 1 cm ligated intestinal loop including Peyer's patch was set up. 3. Bacteria taken up by M cells were fluorescently labeled by fluorescence labeling reagent or by overexpressing fluorescent protein such as green fluorescent protein (GFP). 4. M cells in the follicle-associated epithelium covering Peyer's patch were detected by whole-mount immunostainig with anti Gp2 antibody. 5. Fluorescent bacterial transcytosis by M cells were observed by confocal microscopic analysis. The mouse Peyer's patch intestinal loop assay could supply the answer what kind of commensal or pathogenic bacteria transcytosed by M cells, and may lead us to understand the molecular mechanism of how to stimulate mucosal immune system through M cells.

Application of a Mouse Ligated Peyer&amp;#8217;s Patch Intestinal Loop Assay to Evaluate Bacterial Uptake by M cells

M cells in a specialized follicle-associated epithelium covering Peyer&#x2019;s patches play an important role for the mucosal immunosurveillance in gut-associated lymphoid tissue. Here we described the evaluation method for bacterial transcytosis by M cells in vivo. This method provides a method to understand M-cell function in the immune system.

The inside of our gut is inhabited with enormous number of commensal bacteria. The mucosal surface of the gastrointestinal tract is continuously exposed ...

Establishing a Liquid-covered Culture of Polarized Human Airway Epithelial Calu-3 Cells to Study Host Cell Response to Respiratory Pathogens In vitro

The apical and basolateral surfaces of airway epithelial cells demonstrate directional responses to pathogen exposure in vivo. Thus, ideal in vitro models for examining cellular responses to respiratory pathogens polarize, forming apical and basolateral surfaces. One such model is differentiated normal human bronchial epithelial cells (NHBE). However, this system requires lung tissue samples, expertise isolating and culturing epithelial cells from tissue, and time to generate an air-liquid interface culture.
Calu-3 cells, derived from a human bronchial adenocarcinoma, are an alternative model for examining the response of proximal airway epithelial cells to respiratory insult1, pharmacological compounds2-6, and bacterial7-9 and viral pathogens, including influenza virus, rhinovirus and severe acute respiratory syndrome - associated coronavirus10-14. Recently, we demonstrated that Calu-3 cells are susceptible to respiratory syncytial virus (RSV) infection in a manner consistent with NHBE15,16 . Here, we detail the establishment of a polarized, liquid-covered culture (LCC) of Calu-3 cells, focusing on the technical details of growing and culturing Calu-3 cells, maintaining cells that have been cultured into LCC, and we present the method for performing respiratory virus infection of polarized Calu-3 cells.
To consistently obtain polarized Calu-3 LCC, Calu-3 cells must be carefully subcultured before culturing in Transwell inserts. Calu-3 monolayer cultures should remain below 90% confluence, should be subcultured fewer than 10 times from frozen stock, and should regularly be supplied with fresh medium. Once cultured in Transwells, Calu-3 LCC must be handled with care. Irregular media changes and mechanical or physical disruption of the cell layers or plates negatively impact polarization for several hours or days. Polarization is monitored by evaluating trans-epithelial electrical resistance (TEER) and is verified by evaluating the passive equilibration of sodium fluorescein between the apical and basolateral compartments17,18 . Once TEER plateaus at or above 1,000 &Omega;&times;cm2, Calu-3 LCC are ready to use to examine cellular responses to respiratory pathogens.

Establishing a Liquid-covered Culture of Polarized Human Airway Epithelial Calu-3 Cells to Study Host Cell Response to Respiratory Pathogens In vitro

The findings and conclusions in this report are those of the authors and do not necessarily represent the views of the Centers for Disease Control and Prevention.

The  apical and basolateral surfaces of airway epithelial cells demonstrate  directional responses to pathogen exposure in  vivo. Thus, ideal in vitro ...

Isolation of Myeloid Dendritic Cells and Epithelial Cells from Human Thymus

In this protocol we provide a method to isolate dendritic cells (DC) and epithelial cells (TEC) from the human thymus. DC and TEC are the major antigen presenting cell (APC) types found in a normal thymus and it is well established that they play distinct roles during thymic selection. These cells are localized in distinct microenvironments in the thymus and each APC type makes up only a minor population of cells. To further understand the biology of these cell types, characterization of these cell populations is highly desirable but due to their low frequency, isolation of any of these cell types requires an efficient and reproducible procedure. This protocol details a method to obtain cells suitable for characterization of diverse cellular properties. Thymic tissue is mechanically disrupted and after different steps of enzymatic digestion, the resulting cell suspension is enriched using a Percoll density centrifugation step. For isolation of myeloid DC (CD11c+), cells from the low-density fraction (LDF) are immunoselected by magnetic cell sorting. Enrichment of TEC populations (mTEC, cTEC) is achieved by depletion of hematopoietic (CD45hi) cells from the low-density Percoll cell fraction allowing their subsequent isolation via fluorescence activated cell sorting (FACS) using specific cell markers. The isolated cells can be used for different downstream applications.

This protocol details a method to isolate antigen presenting cells from human thymus via different steps of enzymatic digestion of the tissue followed by density centrifugation of the single cell suspension and finally magnetic and/or FACS sorting of the cell populations of interest.

In this protocol we provide a method to isolate dendritic cells (DC) and epithelial cells (TEC) from the human thymus. DC and TEC are the major antigen ...

Methods for Quantitative Detection of Antibody-induced Complement Activation on Red Blood Cells

Antibodies against red blood cells (RBCs) can lead to complement activation resulting in an accelerated clearance via complement receptors in the liver (extravascular hemolysis) or leading to intravascular lysis of RBCs. Alloantibodies (e.g. ABO) or autoantibodies to RBC antigens (as seen in autoimmune hemolytic anemia, AIHA) leading to complement activation are potentially harmful and can be - especially when leading to intravascular lysis - fatal1. Currently, complement activation due to (auto)-antibodies on RBCs is assessed in vitro by using the Coombs test reflecting complement deposition on RBC or by a nonquantitative hemolytic assay reflecting RBC lysis1-4. However, to assess the efficacy of complement inhibitors, it is mandatory to have quantitative techniques. Here we describe two such techniques. First, an assay to detect C3 and C4 deposition on red blood cells that is induced by antibodies in patient serum is presented. For this, FACS analysis is used with fluorescently labeled anti-C3 or anti-C4 antibodies. Next, a quantitative hemolytic assay is described. In this assay, complement-mediated hemolysis induced by patient serum is measured making use of spectrophotometric&#160;detection of the released hemoglobin. Both of these assays are very reproducible and quantitative, facilitating studies of antibody-induced complement activation.

Here we describe two assays for measuring complement activation induced by antibodies against red blood cells. The major advantage over the current assays is their quantitative and easy-to-interpret nature.

Antibodies against red blood cells (RBCs) can lead to complement activation resulting in an accelerated clearance via complement receptors in the liver ...

Large-Scale Purification of Porcine or Bovine Photoreceptor Outer Segments for Phagocytosis Assays on Retinal Pigment Epithelial Cells

Analysis of one of the vital functions of retinal pigment epithelial (RPE) cells, the phagocytosis of spent aged distal fragments of photoreceptor outer segments (POS) can be performed in vitro. Photoreceptor outer segments with stacks of membranous discs containing the phototransduction machinery are continuously renewed in the retina. Spent POS are eliminated daily by RPE cells. Rodent, porcine/bovine and human RPE cells recognize POS from various species in a similar manner. To facilitate performing large series of experiments with little variability, a large stock of POS can be isolated from porcine eyes and stored frozen in aliquots. This protocol takes advantage of the characteristic of photopigments that display an orange color when kept in the dark. Under dim red light, retinae are collected in a buffer from opened eyecups cut in halves. The retinal cell suspension is homogenized, filtered and loaded onto a continuous sucrose gradient. After centrifugation, POS are located in a discrete band in the upper part of the gradient that has a characteristic orange color. POS are then collected, spun, resuspended sequentially in wash buffers, counted and aliquoted. POS obtained this way can be used for phagocytosis assays and analysis of protein activation, localization or interaction at various times after POS challenge. Alternatively, POS can be labeled with fluorophores, e.g., FITC, before aliquoting for subsequent fluorescence quantification of POS binding or engulfment. Other possible applications include the use of modified POS or POS challenge combined with stress conditions to study the effect of oxidative stress or aging on RPE cells.

This article describes the protocol for the purification of photoreceptor outer segment fragments (POS) via ultracentrifugation from porcine/bovine retinae using homogenization and sucrose gradient centrifugation. This protocol allows the preparation of large stocks of POS aliquots, labeled or unlabeled, that can then be stored at -80 &#176;C.

Analysis of one of the vital functions of retinal pigment epithelial (RPE) cells, the phagocytosis of spent aged distal fragments of photoreceptor outer ...

Phenotypic and Functional Analysis of Activated Regulatory T Cells Isolated from Chronic Lymphocytic Choriomeningitis Virus-infected Mice

Regulatory T (Treg) cells, which express Foxp3 as a transcription factor, are subsets of CD4+ T cells. Treg cells play crucial roles in immune tolerance and homeostasis maintenance by regulating the immune response. The primary role of Treg cells is to suppress the proliferation of effector T (Teff) cells and the production of cytokines such as IFN-&#947;, TNF-&#945;, and IL-2. It has been demonstrated that Treg cells&#39; ability to inhibit the function of Teff cells is enhanced during persistent pathogen infection and cancer development. To clarify the function of Treg cells under resting or inflamed conditions, a variety of in vitro suppression assays using mouse or human Treg cells have been devised. The main aim of this study is to develop a method to compare the differences in phenotype and suppressive function between resting and activated Treg cells. To isolate activated Treg cells, mice were infected with lymphocytic choriomeningitis virus (LCMV) clone 13 (CL13), a chronic strain of LCMV. Treg cells isolated from the spleen of LCMV CL13-infected mice exhibited both the activated phenotype and enhanced suppressive activity compared with resting Treg cells isolated from na&#239;ve mice. Here, we describe the basic protocol for ex vivo phenotype analysis to distinguish activated Treg cells from resting Treg cells. Furthermore, we describe a protocol for the measurement of the suppressive activity of fully activated Treg cells.

Here, we describe a protocol to analyze the phenotype of regulatory T (Treg) cells isolated from na&#239;ve and chronic lymphocytic choriomeningitis virus-infected mice. In addition, we provide a process to evaluate the suppressive activity of the Treg cells.

Regulatory T (Treg) cells, which express Foxp3 as a transcription factor, are subsets of CD4+ T cells. Treg cells play crucial roles in immune tolerance ...

Noninvasive Sampling of Mucosal Lining Fluid for the Quantification of In Vivo Upper Airway Immune-mediator Levels

This protocol describes noninvasive sampling of undisturbed upper airway mucosal lining fluid. It also details the extraction procedure used prior to the analysis of immune mediators in fluid eluates for the study of the airway topical immune signature, without the need for stimulation procedures (often used by other techniques). The mucosal lining fluid is sampled on a strip of filter paper placed at the anterior part of the inferior turbinate and left for 2 min of absorption. Analytes are eluted from the filter papers, and the extracted protein-based eluates are analyzed by an electrochemiluminescence-based immunoassay, allowing for the high-sensitivity quantification of low- and high-level analytes in the same sample. We measured the in vivo levels of 20 preselected immune mediators related to specific immune signaling pathways in the upper airway mucosa, but the technique is not limited to that specific panel or sampling site. The technique was first implemented in 7-year-old children from the Copenhagen Prospective Studies on Asthma in Childhood2000 (COPSAC2000) cohort with allergic rhinitis. It was thereafter used in the longitudinal COPSAC2010 birth cohort, sampled at 1 month, 2 years, and 6 years of age and at instances of acute respiratory symptoms. We successfully obtained and analyzed samples from 620 (89%) of 700 1-month-old children; a few samples were below the assay detection limit (reported as the median (Inter-Quartile Range (IQR)). The number of samples below the detection limit (i.e.&#160;from 0 to the set point for the lower limit of detection) for each mediator was 29 (7.25 - 119.5). This technique enables the quantification of the in vivo airway mucosal immune profile from birth, can be applied longitudinally, and can be applied to studies on the effect of genetics and early-life environmental exposures, pathophysiology, endotyping, and monitoring of respiratory diseases, and development and evaluation of novel therapeutics.

Noninvasive Sampling of Mucosal Lining Fluid for the Quantification of In Vivo Upper Airway Immune-mediator Levels

This protocol describes a noninvasive technique for the sampling of undisturbed mucosal lining fluid from the upper airways. It can be used to perform the quantification of in vivo levels of protein mediators, such as cytokines and chemokines, in subjects of all ages.

This protocol describes noninvasive sampling of undisturbed upper airway mucosal lining fluid. It also details the extraction procedure used prior to the ...

Isolation and Characterization of Neutrophil-derived Microparticles for Functional Studies

Polymorphonuclear neutrophil-derived microparticles (PMN)-MPs) are lipid bilayer, spherical microvesicles with sizes ranging from 50&#8211;1,000 nm in diameter. MPs are a newly evolving, important part of cell-to-cell communication and signaling machinery. Because of their size and the nature of their release, until recently MP existence was overlooked. However, with improved technology and analytical methods their function in health and disease is now emerging. The protocols presented here are aimed at isolating and characterizing PMN-MPs by flow cytometry and immunoblotting. Moreover, several implementation examples are given. These protocols for MP isolation are fast, low-cost, and do not require the use of expensive kits. Furthermore, they allow for the labeling of MPs following isolation, as well as pre-labeling of source cells prior to MP release, using a membrane-specific fluorescent dye for visualization and analysis by flow cytometry. These methods, however, have several limitations including purity of PMNs and MPs and the need for sophisticated analytical instrumentation. A high-end flow cytometer is needed to reliably analyze MPs and minimize false positive reads due to noise or auto-fluorescence. The described protocols can be used to isolate and define MP biogenesis, and characterize their markers and variation in composition under different stimulating conditions. Size heterogeneity can be exploited to investigate whether the content of membrane particles versus exosomes is different, and whether they fulfill different roles in tissue homeostasis. Finally, following isolation and characterization of MPs, their function in cellular responses and various disease models (including, PMN-associated inflammatory disorders, such as Inflammatory Bowel Diseases or Acute Lung Injury) can be explored.

New protocols are described here to isolate and characterize microparticles derived from human and mouse neutrophils. These protocols utilize ultracentrifugation, flow cytometry, and immunoblotting techniques to analyze microparticle content, and they can be used to study the role of microparticles derived from various cell types in cellular function.

Polymorphonuclear neutrophil-derived microparticles (PMN)-MPs) are lipid bilayer, spherical microvesicles with sizes ranging from 50&#8211;1,000 nm in ...