Name: visualizing macrophage extracellular traps using confocal microscopy
Uploaded: 2017-10-19T14:00:00
Description: Watch this Scientific Journal Video about Visualizing Macrophage Extracellular Traps Using Confocal Microscopy at JoVE.com

Este trabajo fue financiado por becas de la Universidad de Monash, la salud nacional y Consejo de investigación médica y el pulmón de Monash e Instituto del sueño. Los autores desean dar las gracias al personal de inmunología clínica en salud de Monash, Judy Callaghan, Alex Fulcher, Kirstin Elgass y Camden Lo de Monash Micro Imaging (MMI) ayuda con la microscopía confocal de imágenes, y los autores reconocen las instalaciones MMI de la Universidad de Monash. Los autores reconocen las instalaciones y asistencia científica y técnica de la plataforma de la histología de Monash.

este protocolo sigue experimentos aprobados en: (1) los seres humanos por el Comité de ética de Monash Medical Centre y (2) animales por el Comité de ética de la Universidad de Melbourne.
 1. macrófagos de lavado broncoalveolar (BAL) <ol><li>BAL de uso para obtener los macrófagos del pulmón en: (1) humanos sujetos por broncoscopia 6 y (2) ratones utilizando aspiración intra traqueal 13 . 
	Nota: La adquisición de los macrófago...

<ol>
	<li>Brinkmann, V., 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=Neutrophil+extracellular+traps+kill+bacteria.">Neutrophil extracellular traps kill bacteria.</a> Science. 303 (5663), 1532-1535 (2004).</li><li>Brinkmann, V., Zychlinsky, A. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Neutrophil+extracellular+traps:+is+immunity+the+second+function+of+chromatin?.">Neutrophil extracellular traps: is immunity the second function of chromatin?.</a> J Cell Biol. 198 (5), 773-783 (2012).</li><li>Jorch, S. K., Kubes, P. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=An+emerging+role+for+neutrophil+extracellular+traps+in+noninfectious+disease.">An emerging role for neutrophil extracellular traps in noninfectious disease.</a> Nat Med. 23 (3), 279-287 (2017).</li><li>Cheng, O. Z., Palaniyar, N. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=NET+balancing:+a+problem+in+inflammatory+lung+diseases.">NET balancing: a problem in inflammatory lung diseases.</a> Frontiers immunol. 4, 1 (2013).</li><li>Boe, D. M., Curtis, B. J., Chen, M. M., Ippolito, J. A., Kovacs, E. J. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Extracellular+traps+and+macrophages:+new+roles+for+the+versatile+phagocyte.">Extracellular traps and macrophages: new roles for the versatile phagocyte.</a> J Leukoc Biol. 97 (6), 1023-1035 (2015).</li><li>King, P. 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=Nontypeable+Haemophilus+influenzae+induces+sustained+lung+oxidative+stress+and+protease+expression.">Nontypeable Haemophilus influenzae induces sustained lung oxidative stress and protease expression.</a> PloS one. 10 (3), e0120371 (2015).</li><li>O'Sullivan, K. M., 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=Renal+participation+of+myeloperoxidase+in+antineutrophil+cytoplasmic+antibody+(ANCA)-associated+glomerulonephritis.">Renal participation of myeloperoxidase in antineutrophil cytoplasmic antibody (ANCA)-associated glomerulonephritis.</a> Kidney Int. 88 (5), 1030-1046 (2015).</li><li>Fuchs, T. A., 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=Novel+cell+death+program+leads+to+neutrophil+extracellular+traps.">Novel cell death program leads to neutrophil extracellular traps.</a> J Cell Biol. 176 (2), 231-241 (2007).</li><li>Wang, Y., 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=Histone+hypercitrullination+mediates+chromatin+decondensation+and+neutrophil+extracellular+trap+formation.">Histone hypercitrullination mediates chromatin decondensation and neutrophil extracellular trap formation.</a> J Cell Biol. 184 (2), 205-213 (2009).</li><li>Papayannopoulos, V., Metzler, K. D., Hakkim, A., Zychlinsky, A. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Neutrophil+elastase+and+myeloperoxidase+regulate+the+formation+of+neutrophil+extracellular+traps.">Neutrophil elastase and myeloperoxidase regulate the formation of neutrophil extracellular traps.</a> J Cell Biol. 191 (3), 677-691 (2010).</li><li>Rohrbach, A. S., Slade, D. J., Thompson, P. R., Mowen, K. A. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Activation+of+PAD4+in+NET+formation.">Activation of PAD4 in NET formation.</a> Front Immunol. 3, 360 (2012).</li><li>Lewis, H. D., 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=Inhibition+of+PAD4+activity+is+sufficient+to+disrupt+mouse+and+human+NET+formation.">Inhibition of PAD4 activity is sufficient to disrupt mouse and human NET formation.</a> Nat Chem Biol. 11 (3), 189-191 (2015).</li><li>Ruwanpura, S. M., McLeod, L., Dousha, L. F., 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=Therapeutic+Targeting+of+the+IL-6+Trans-Signaling/Mechanistic+Target+of+Rapamycin+Complex+1+Axis+in+Pulmonary+Emphysema.">Therapeutic Targeting of the IL-6 Trans-Signaling/Mechanistic Target of Rapamycin Complex 1 Axis in Pulmonary Emphysema.</a> Am J Respir Crit Care Med. 194 (12), 1494-1505 (2016).</li><li>Brinkmann, V., Laube, B., Abu Abed, U., Goosmann, C., Zychlinsky, A. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Neutrophil+extracellular+traps:+how+to+generate+and+visualize+them.">Neutrophil extracellular traps: how to generate and visualize them.</a> Journal of visualized experiments : JoVE. (36), (2010).</li><li>Chow, O. A., von Kockritz-Blickwede, M., Bright, A. 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=Statins+enhance+formation+of+phagocyte+extracellular+traps.">Statins enhance formation of phagocyte extracellular traps.</a> Cell host &amp; microbe. 8 (5), 445-454 (2010).</li><li>Wong, K. W., Jacobs, W. R. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Mycobacterium+tuberculosis+exploits+human+interferon+gamma+to+stimulate+macrophage+extracellular+trap+formation+and+necrosis.">Mycobacterium tuberculosis exploits human interferon gamma to stimulate macrophage extracellular trap formation and necrosis.</a> J Infect Dis. 208 (1), 109-119 (2013).</li></ol>

El método descrito en este informe se basa en que para la determinación de la presencia de redes14. Los macrófagos son el tipo celular dominante en muestras de BAL y este método de colección es especialmente adecuado para el estudio de METs. Si glóbulos rojos están presentes en el BAL, estas células deben lisis mediante el uso de cloruro de amonio. El procedimiento de BAL generalmente activa los macrófagos y por lo tanto se espera que habrá METs presentes en las muestras no estimuladas. ...

Neutrófilos trampas extracelulares (redes), primero fueron descritos por Brinkmann et al. 1 que predominantemente se producen en respuesta a la infección (especialmente a las bacterias) y tienen un papel importante en host defense1,2. También se han descrito para ocurrir en respuesta a enfermedades no infecciosas, incluyendo vasculitis y lupus eritematoso sistémico (les); y a los mitógenos forbol 12-myrisate 13-acetato (PMA)2,3. Se ha reconocido recientemente que otros tipos celulares pueden también producir trampas extracelulares, incluyendo los macrófagos. Trampas extracelulares del macrófago (MET) todavía no son una entidad bien definida en la literatura4,5. Recientemente hemos establecido los métodos para detectar la presencia de METs tanto in vitro e in vivo6,7. En este artículo, se describen la medida de METs usando microscopia confocal.
Características clave de NETosis que la distinguen de otras vías celulares (tales como apoptosis8) son la extrusión de la cromatina en relación con: (1) citrullination de histonas (H3Cit)9, (2) la expresión de proteasas de gránulo10 y (3) participación de peptidil arginina deiminase (PAD) 411,12. Macrófagos también expresan H3Cit, proteasas de gránulo y almohadilla, y estas características pueden utilizarse para definir la presencia de METs.
METs de pueden tener un papel particularmente importante en el pulmón, como el macrófago es la célula dominante presente en los alvéolos y las vías respiratorias del pulmón y tiene la función inicial en la dirección del cellular la respuesta inmune a la infección/inflamación. Además, mientras que gran parte del pulmón es espacio vacío (por ejemplo, dentro de los alvéolos), los METs son potencialmente capaces de expandirse en el espacio disponible, a diferencia de órganos sólidos.
El método más utilizado para definir la presencia de redes es mediante microscopía confocal. Aún no existe una forma claramente definida para medir METs. La técnica para la medición de redes ha sido adaptada para medir la presencia de METs en el presente Protocolo. Los principales requisitos para este método son el acceso a la microscopia confocal y el software apropiado de imágenes para análisis.

<table>
	<tbody>
		<tr>
			<td>Human samples: Primary antibodies</td>
			<td></td>
			<td></td>
			<td></td>
		</tr>
		<tr>
			<td>Rabbit anti-human H3Cit (Citrulline R26)</td>
			<td>Abcam</td>
			<td>AB5103</td>
			<td>10 ug/ml</td>
		</tr>
		<tr>
			<td>Rabbit anti-human MMP12</td>
			<td>Novus Biological</td>
			<td>NB110-57214</td>
			<td>1:100 concentration not quantifiable</td>
		</tr>
		<tr>
			<td>Mouse anti-human MMP9</td>
			<td>Novus Biological</td>
			<td>AB119906</td>
			<td>1:200 ascites, no concentration given</td>
		</tr>
		<tr>
			<td>Rabbit anti-human PADI2/PAD2</td>
			<td>Abcam</td>
			<td>AB16478</td>
			<td>7 ug/ml</td>
		</tr>
		<tr>
			<td>Mouse anti-human PADI4/PAD4</td>
			<td>Abcam</td>
			<td>AB128086</td>
			<td>10.1 ug/ml</td>
		</tr>
		<tr>
			<td>Sheep anti-human NE</td>
			<td>LifeSpan Bioscience</td>
			<td>LS-B4244</td>
			<td>25 ug/ml</td>
		</tr>
		<tr>
			<td>Name</td>
			<td>Company</td>
			<td>Catalog Number</td>
			<td>Comments</td>
		</tr>
		<tr>
			<td>Mouse samples: Primary antibodies</td>
			<td></td>
			<td></td>
			<td></td>
		</tr>
		<tr>
			<td>Goat anti-mouse MMP9</td>
			<td>Abcam</td>
			<td>AF909</td>
			<td>10 ug/ml</td>
		</tr>
		<tr>
			<td>Rabbit anti-mouse H3Cit (Citrulline R26)</td>
			<td>Abcam</td>
			<td>AB5103</td>
			<td>10 ug/ml</td>
		</tr>
		<tr>
			<td>Rat anti-mouse F4/80</td>
			<td>In-house (hybridoma)</td>
			<td>In house</td>
			<td>20 ug/ml</td>
		</tr>
		<tr>
			<td>Sheep anti-human Anti-HNE /NE</td>
			<td>Sapphire Bioscience</td>
			<td>LS-B4244</td>
			<td>25 ug/ml</td>
		</tr>
		<tr>
			<td>Mouse anti-human &#173;&#173;&#173;&#173;PADI4/PAD4</td>
			<td>Abcam</td>
			<td>AB128086</td>
			<td>10.1 ug/ml</td>
		</tr>
		<tr>
			<td>Super-frost plus slides</td>
			<td>Menzel</td>
			<td>S41104A</td>
			<td></td>
		</tr>
		<tr>
			<td>Dapi-prolong gold</td>
			<td>Molecular probes</td>
			<td>P36931</td>
			<td></td>
		</tr>
		<tr>
			<td>Triton-X 100</td>
			<td>Sigma-Aldrich</td>
			<td>85111</td>
			<td></td>
		</tr>
		<tr>
			<td>Ammonium chloride</td>
			<td>Sigma-Aldrich</td>
			<td>E9434</td>
			<td></td>
		</tr>
		<tr>
			<td>Name</td>
			<td>Company</td>
			<td>Catalog Number</td>
			<td>Comments</td>
		</tr>
		<tr>
			<td>Secondary antibodies</td>
			<td></td>
			<td></td>
			<td></td>
		</tr>
		<tr>
			<td>Chicken anti-rabbit AF 488/</td>
			<td>Life technologies</td>
			<td>A-21441</td>
			<td></td>
		</tr>
		<tr>
			<td>Chicken anti-rabbit AF 594</td>
			<td>Life technologies</td>
			<td>A-21442</td>
			<td></td>
		</tr>
		<tr>
			<td>Chicken anti-goat AF 594</td>
			<td>Life technologies</td>
			<td>a-21468</td>
			<td></td>
		</tr>
		<tr>
			<td>Chicken anti-mouse AF488</td>
			<td>Life technologies</td>
			<td>A-21200</td>
			<td></td>
		</tr>
		<tr>
			<td>Donkey anti-sheep AF 594</td>
			<td>Life technologies</td>
			<td>A-11018</td>
			<td></td>
		</tr>
		<tr>
			<td>Chicken anti-mouse AF 647</td>
			<td>Life technologies</td>
			<td>A-21463</td>
			<td></td>
		</tr>
		<tr>
			<td>Donkey anti-sheep AF 594</td>
			<td>Life technologies</td>
			<td>A-11016</td>
			<td></td>
		</tr>
		<tr>
			<td>Isotype control</td>
			<td></td>
			<td></td>
			<td></td>
		</tr>
		<tr>
			<td>Rabbit IgG</td>
			<td>In house</td>
			<td></td>
			<td></td>
		</tr>
		<tr>
			<td>Rabbit IgG</td>
			<td>In house</td>
			<td></td>
			<td></td>
		</tr>
		<tr>
			<td>Mouse IgG1</td>
			<td>BD Bioscience</td>
			<td>550878</td>
			<td></td>
		</tr>
		<tr>
			<td>Rabbit IgG</td>
			<td>In house</td>
			<td></td>
			<td></td>
		</tr>
		<tr>
			<td>Mouse IgG2a</td>
			<td>BioLegend</td>
			<td>400201</td>
			<td></td>
		</tr>
		<tr>
			<td>Sheep IgG</td>
			<td>In house</td>
			<td></td>
			<td></td>
		</tr>
		<tr>
			<td>Name</td>
			<td>Company</td>
			<td>Catalog Number</td>
			<td>Comments</td>
		</tr>
		<tr>
			<td>Software Programs</td>
			<td></td>
			<td></td>
			<td></td>
		</tr>
		<tr>
			<td>Imaris</td>
			<td>Bitplane</td>
			<td></td>
			<td></td>
		</tr>
		<tr>
			<td>Image J</td>
			<td>NIH</td>
			<td></td>
			<td></td>
		</tr>
		<tr>
			<td>To average intensity of fluorphores a standard office application like Microsoft Excel can be used</td>
			<td></td>
			<td></td>
			<td></td>
		</tr>
		<tr>
			<td>Name</td>
			<td>Company</td>
			<td>Catalog Number</td>
			<td>Comments</td>
		</tr>
		<tr>
			<td>Microscopes</td>
			<td></td>
			<td></td>
			<td></td>
		</tr>
		<tr>
			<td>C1 Confocal scanning microscope</td>
			<td>Nikon</td>
			<td></td>
			<td></td>
		</tr>
		<tr>
			<td>FV1200 Confocal scanning microscope</td>
			<td>Olympus</td>
			<td></td>
			<td></td>
		</tr>
		<tr>
			<td>Name</td>
			<td>Company</td>
			<td>Catalog Number</td>
			<td>Comments</td>
		</tr>
		<tr>
			<td>Tissue sources</td>
			<td></td>
			<td></td>
			<td></td>
		</tr>
		<tr>
			<td>Human BAL samples from the bronchoscopy suite at Monash Medical Centre</td>
			<td></td>
			<td></td>
			<td></td>
		</tr>
		<tr>
			<td>Mouse BAL samples and lung tissue from the Department of Pharmacology, University of Melbourne.</td>
			<td></td>
			<td></td>
			<td></td>
		</tr>
		<tr>
			<td>Name</td>
			<td>Company</td>
			<td>Catalog Number</td>
			<td>Comments</td>
		</tr>
		<tr>
			<td>Media</td>
			<td></td>
			<td></td>
			<td></td>
		</tr>
		<tr>
			<td>RPMI</td>
			<td>Sigma-Aldrich</td>
			<td>r8758</td>
			<td></td>
		</tr>
		<tr>
			<td>Fetal calf serum</td>
			<td>Sigma-Aldrich</td>
			<td>F0926</td>
			<td></td>
		</tr>
		<tr>
			<td>L-glutamine</td>
			<td>Sigma-Aldrich</td>
			<td>G7513</td>
			<td></td>
		</tr>
		<tr>
			<td>Name</td>
			<td>Company</td>
			<td>Catalog Number</td>
			<td>Comments</td>
		</tr>
		<tr>
			<td>Other reagents</td>
			<td></td>
			<td></td>
			<td></td>
		</tr>
		<tr>
			<td>Sudan black</td>
			<td>Sigma-Aldrich</td>
			<td>199664</td>
			<td></td>
		</tr>
		<tr>
			<td>paraformaldehyde/periodate/lysine (PLP) fixative</td>
			<td>Sigma-Aldrich</td>
			<td>27387</td>
			<td></td>
		</tr>
		<tr>
			<td>Xylene</td>
			<td>Sigma-Aldrich</td>
			<td>214736</td>
			<td></td>
		</tr>
		<tr>
			<td>Ketamine</td>
			<td>Sigma-Aldrich</td>
			<td>K2753</td>
			<td></td>
		</tr>
		<tr>
			<td>Natural formalin</td>
			<td>Sigma-Aldrich</td>
			<td>42904</td>
			<td></td>
		</tr>
		<tr>
			<td>Paraffin</td>
			<td>Sigma-Aldrich</td>
			<td>327204</td>
			<td></td>
		</tr>
		<tr>
			<td>Agarose</td>
			<td>Sigma-Aldrich</td>
			<td>A2576</td>
			<td></td>
		</tr>
		<tr>
			<td>Solvent 3B</td>
			<td>Hi-Chem</td>
			<td>2026</td>
			<td></td>
		</tr>
		<tr>
			<td>Coverslips 12 ml</td>
			<td>Sigma-Aldrich</td>
			<td>S1815</td>
			<td></td>
		</tr>
		<tr>
			<td>Coverslips 60 x 24 ml</td>
			<td>Sigma-Aldrich</td>
			<td>C6875</td>
			<td></td>
		</tr>
		<tr>
			<td>Name</td>
			<td>Company</td>
			<td>Catalog Number</td>
			<td>Comments</td>
		</tr>
		<tr>
			<td>Mice</td>
			<td></td>
			<td></td>
			<td></td>
		</tr>
		<tr>
			<td>c57 black 6</td>
			<td>Monash animal research platform (MARP)</td>
			<td></td>
			<td></td>
		</tr>
		<tr>
			<td>BALB/c</td>
			<td>MARP</td>
			<td></td>
			<td></td>
		</tr>
	</tbody>
</table>

visualizing macrophage extracellular traps using confocal microscopy

Un método primario utilizado para definir la presencia de neutrófilos trampas extracelulares (redes) es la microscopia confocal. Hemos modificado microscopía confocal establecido métodos para visualizar las trampas extracelulares del macrófago (MET). Estas trampas extracelulares se definen por la presencia de cromatina extracelular con coexpresión de otros componentes como gránulo proteasas, las histonas citrulinado y peptidil arginasa deiminase (PAD). La expresión de METs es generalmente medida después de la exposición a un estímulo y en comparación con muestras no estimuladas. Las muestras también se incluyen para el control del fondo y el isotipo. Las células son analizadas utilizando el software de análisis de imagen bien definida. La microscopia confocal puede utilizarse para definir la presencia de METs en vitro y en vivo en el tejido pulmonar.

METs se pueden visualizar de muestras de BAL, en tejido pulmonar y en secciones gruesas de pulmón con imágenes 3D. En la figura 1se muestra un ejemplo de METs visualizado en una muestra de BAL. La morfología de los METs variarán según su etapa de maduración. La primera característica detectable en microscopia es el movimiento del núcleo al borde de la celda. Esto es seguido por cromatina extracelular con otros mediadores Co expresados, como proteasas ...

Watch this Scientific Journal Video about Visualizing Macrophage Extracellular Traps Using Confocal Microscopy at JoVE.com

Visualizing Macrophage Extracellular Traps Using Confocal Microscopy

Las trampas extracelulares macrófago son una entidad nuevamente descrita. Este artículo se centrará en los métodos de microscopía confocal y cómo son visualizados en vitro y en vivo de las muestras de pulmón.

Visualización de macrófagos trampas extracelular mediante Microscopía Confocal

A primary method used to define the presence of neutrophil extracellular traps (NETs) is confocal microscopy. We have modified established confocal ...

The overall goal of this method is to demonstrate how macrophage extracellular traps can be visualized and studied using confocal microscopy. This method can help answer key questions in the inflammation field, such as responses to infection and other immune stimuli. The main advantage of this technique is that it is a modification of a well established method that has been used to study neutrophil extracellular traps.Demonstrating this procedure will be Roleen Sharma. After obtaining lung macrophages from humans and mice by bronchoalveolar lavage, or BAL, according to the text protocol, use trypan blue and a hemocytometer to perform a viable cell count on the BAL solution. Pipette one to four times 10 to the fifth macrophages in 500 microliters of culture medium onto cover slips in the wells of 24-well plates, then incubate the cells at 37 degrees Celsius overnight for the cells to adhere.Remove the culture medium and use PBS to wash the cells once. Then add 2%paraformaldehyde-periodate-lysine, or PLP fixative, and incubate the samples for 10 minutes. After using PBS to briefly wash the cells, add 0.2%TWEEN 20 in PBS and incubate the cells for 20 minutes.Next, to block the cells, add 10%chicken serum in 5%BSA, diluted in PBS and incubate the samples at room temperature for 30 minutes. Then replace the block solution with a one to 100 concentration of primary and isotope control antibodies and incubate the cells at room temperature for one hour. Following the incubation, use PBS to wash the cells before adding the corresponding secondary antibodies.Then incubate the samples for 40 minutes at room temperature. After washing the cells in PBS, mount the samples with DAPI based mounting medium, then visualize the samples using a confocal microscope. To pretreat the FFPE samples with antigen retrieval solution, oven dry the slides at 60 degrees Celsius for 60 minutes.Then transfer the slides into xylene solution for 30 minutes before transferring the samples to 70%ethanol at room temperature for five minutes. After using tap water to rinse the slides, place them in heat-proof plastic wrap and subject them to higher antigen retrieval by placing them in a pressure cooker in Tris-EDTA pH 9.0 for 10 minutes. Cool the samples for 20 minutes and transfer them to tap water.Then place them on a rocker for five minutes. Repeat the tap water wash and then wash the slides once in PBS on the rocker. To block the samples, add 10%chicken serum in 5%BSA PBS and incubate them at room temperature for 30 minutes.Then, to define macrophage extracellular traps, or METs in macrophages, add a one to 100 dilution of primary antibodies in 1%BSA PBS and incubate the slides at four degrees Celsius for 16 hours. Use PBS to wash the samples two times on a rocker for five minutes each. Add the corresponding fluorescent secondary antibodies in 1%BSA PBS and incubate the slides at room temperature for 40 minutes.Following PBS washes, use DAPI containing mounting medium to stain the chromatin and mount the samples. Using a confocal laser scanning head attached to an inverted microscope, capture fluorescent images using 20X 0.1 NA air and 40X 1.0 NA oil objectives. Capture single plane 512 by 512 pixel images by clicking on the Line Sequential leveling button.Obtain at least 10 fields of view per section for analysis and data for each result. To stain the sections in microcentrifuge tubes, add the relevant primary antibodies in 200 microliter volumes and incubate the samples at four degrees Celsius for 16 hours. Wash the sections in PBS three times for 10 minutes before adding the appropriate secondary antibodies and incubating the samples at room temperature for one hour.Use DAPI to stain the lung sections in solution and incubate the samples for 20 minutes before adding cover slips to the sections on microscope slides in PBS. Use an inverted confocal microscope with a 40X 1.3 NA objective, equipped with 405 nanometers, 440 nanometers, 473 nanometers, 543 nanometers, and 635 nanometer lasers, to capture images and to record 3D Z stacks, 0.54 microns thick, with optimal Z sectioning. Finally, analyze the images according to the text protocol.An example of METs in a BAL sample is shown here. The first detectable feature is the movement of the nucleus to the edge of the cell, as seen in this earlier stage MET that has a roughly spherical shape. This is followed by extracellular chromatin with other co-expressed mediators, such as H3Cit and granular proteases, as seen in this more mature MET.Earlier stage MET is upper left and later stage MET is below this towards the center. Lung tissue METs are shown in this figure. As the lungs are inflated with fluid to define the lung architecture, the METs will be pushed against the alveolar walls.The morphology of the METs will also vary depending on in which plane the tissue was cut. The standard sections used for lung tissue samples are four to five microns thick. Thicker tissue sections enable multiple images to be taken and the METs can then be viewed in 3D.An example of a 3D image from mouse lung tissue cut in 25 to 35 micron sections is presented here. Once mastered, this technique can be done in two days of staining plus imaging if it's performed properly. While attempting this procedure, it is important to remember to be gentle with the washes.Following this procedure, other methods like zymography can be performed to answer additional questions like protease expression. After its development, this technique may pave way for the study of inflammatory macrophage responses. After watching this video, you should have a good understanding of how to visualize METs using confocal microscopy.Don't forget that working with PLP can be hazardous and precautions such as wearing gloves and eye protection should always be taken while performing this procedure.

Research

JoVE Journal

Immunology and Infection

Neutrophil Extracellular Traps: How to Generate and Visualize Them

Las trampas de neutrófilos extracelular: Cómo generar y visualizarlas

Neutrophil granulocytes are the most abundant group of leukocytes in the peripheral blood. As professional phagocytes, they engulf bacteria and kill them ...

Investigación

Inmunología e Infección

Visualizing Cell-to-cell Transfer of HIV using Fluorescent Clones of HIV and Live Confocal Microscopy

Visualización de la célula a célula de Transmisión del VIH utilizando clones fluorescente del VIH y la microscopía confocal en vivo

By fusing the green fluorescent protein to their favorite proteins, biologists now have the ability to study living complex cellular processes using ...

Intravital Microscopy of the Spleen: Quantitative Analysis of Parasite Mobility and Blood Flow

Microscopia intravital del bazo: Análisis cuantitativo de la movilidad del parásito y el flujo sanguíneo

The advent of intravital microscopy in experimental rodent malaria models has allowed major advances to the knowledge of parasite-host interactions 1,2. ...

Visualizing Non-lytic Exocytosis of Cryptococcus neoformans from Macrophages Using Digital Light Microscopy

Visualizing Non-lytic Exocytosis of Cryptococcus neoformans from Macrophages Using Digital Light Microscopy

La visualización no lítico exocitosis de<em&gt; Cryptococcus neoformans</em&gt; De macrófagos Usando microscopía de luz digital

Many aspects of the infection of macrophages by Cryptococcus neoformans have been extensively studied and well defined. However, one particular ...

Simplified Human Neutrophil Extracellular Traps (NETs) Isolation and Handling

Simplified Human Neutrophil Extracellular Traps NETs Isolation and Handling

Simplificado Humanos neutrófilos extracelular Trampas (TNE) Aislamiento y manipulación

Neutrophil Extracellular Traps (NETs) have been recently identified as part of the neutrophil&#8217;s antimicrobial armamentarium. Apart from their role ...