Name: phenotypic characterization of macrophages from rat kidney by flow cytometry
Uploaded: 2016-10-18T14:00:00
Description: Watch this Scientific Journal Video about Phenotypic Characterization of Macrophages from Rat Kidney by Flow Cytometry at JoVE.com

This work was supported by grants from FIS/FEDER (Programa Miguel Servet: CP10/00479, PI13/00802 and PI14/00883), Spanish Society of Atherosclerosis, Spanish Society of Nephrology and Fundaci&#242;n Renal I&#241;igo Alvarez de Toledo (FRIAT) to Juan Antonio Moreno. FIS/FEDER funds PI14/00386 and Instituto Reina Sof&#236;a de Investigaci&#242;n Nefrol&#242;gica to Jes&#250;s Egido. Fundaci&#242;n Conchita Rabago to Melania Guerrero Hue. Fundaci&#242;n Renal I&#241;igo Alvarez de Toledo (FRIAT) to Alfonso Rubio Navarro.

This protocol was approved by local Institutional Animal Care and Use Committees following the Directive 2010/63/EU of the European Parliament and the National Guideline 53/2013.
1. Preparation of Reagents and Solutions
<ol>
	<li>Prepare all the reagents and solutions under sterile conditions and use under a laminar flow hood. Keep solutions at 4 &#176;C.</li>
	<li>Prepare staining buffer (2% Fetal Bovine Serum (FBS) in 1x Dulbecco&#39;s PBS).</li>
	<li>Prepare collagenase solution by adding 0.5 mg of collagenas...

<ol>
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Macrophages are heterogeneous cells that play an important role in different inflammatory diseases, including renal disorders. There is increasing interest in the characterization of macrophages subsets in renal disease because each macrophage subpopulation contributes in a different way to the development of kidney injury, as reported in glomerulonephritis, diabetic nephropathy and kidney cancer14-16. In the early stages of acute renal injury, a predominance of M1 macrophages is observed, promoting tubular ne...

Renal disease is a global health problem, with increased prevalence, and associated with elevated morbidity and mortality1. One of the most important mechanisms involved in the progression and development of renal injury is inflammation, mainly triggered by macrophages. Macrophages play a pivotal role in many inflammatory diseases, including renal disorders2. Thus, an elevated presence of infiltrating macrophages has been reported in biopsies from patients with acute kidney injury (AKI) or chronic kidney disease (CKD)3,4. Recent studies suggest that the long-term outcome of renal disease could be controlled by macrophages5,6. In response to the local microenvironment, macrophages may differentiate into different phenotypes that play diverse biological functions7. Two well differentiated macrophage phenotypes have been established: classically activated macrophages (M1 macrophages) and alternatively activated macrophages (M2)8. M1 macrophages promote inflammation, whereas M2 macrophages have an anti-inflammatory role and are involved in tissue repair9. Therefore, a better knowledge of macrophage heterogeneity is necessary to understand their regulation and contribution to renal pathology and develop novel therapeutic approaches. 
Both, murine and rats models have been widely used to understand the molecular and cellular mechanism involved in renal injury10. However, there are substantial differences in the diverse markers used to identify macrophages phenotypes between these rodents. Hence, several murine markers, such as F4/80 or Ly6C are not used in rats, thus limiting the extrapolation of findings between these species. Moreover, there is a limited number of markers describing macrophage phenotypes in rats, explaining the scarce studies analyzing macrophage heterogeneity in these animals as compared with mice. Therefore, new strategies for macrophage subset characterization are necessary to understand the role of macrophages in renal disease models in rats. 
This manuscript describes a protocol for the phenotypic and quantitative analysis of macrophages from rat kidneys by flow cytometry. This technique can be further followed by several assays, including cell sorting and mRNA or protein expression studies to allow in-depth characterization of the role of macrophages in renal disease.

<table border="0" cellpadding="0" cellspacing="0" width="519">
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	</colgroup>
	<tbody>
		<tr height="43">
			<td height="43" style="height:43px;width:119px;">Laminar flow hood</td>
			<td style="width:124px;">Faster</td>
			<td style="width:135px;"></td>
			<td style="width:143px;">Or equivalent equipment</td>
		</tr>
		<tr height="43">
			<td height="43" style="height:43px;width:119px;">Centrifuge</td>
			<td style="width:124px;">Hettich</td>
			<td style="width:135px;"></td>
			<td style="width:143px;">Or equivalent equipment</td>
		</tr>
		<tr height="43">
			<td height="43" style="height:43px;width:119px;">Flow cytometer (FACSAria)</td>
			<td style="width:124px;">BD Biosciences</td>
			<td style="width:135px;"></td>
			<td style="width:143px;"></td>
		</tr>
		<tr height="43">
			<td height="43" style="height:43px;width:119px;">Fetal bovine serum</td>
			<td style="width:124px;">BioWest</td>
			<td style="width:135px;">S1820-500</td>
			<td style="width:143px;"></td>
		</tr>
		<tr height="22">
			<td height="22" style="height:22px;width:119px;">PBS 10x</td>
			<td style="width:124px;">LONZA</td>
			<td style="width:135px;">BE17-515Q</td>
			<td style="width:143px;"></td>
		</tr>
		<tr height="22">
			<td height="22" style="height:22px;width:119px;">Collagenase</td>
			<td style="width:124px;">Sigma-Aldrich</td>
			<td style="width:135px;">12/1/9001</td>
			<td style="width:143px;"></td>
		</tr>
		<tr height="43">
			<td height="43" style="height:43px;width:119px;">ACK Lysing Buffer</td>
			<td style="width:124px;">Thermo Fisher Scientific</td>
			<td style="width:135px;">A10492-01</td>
			<td style="width:143px;"></td>
		</tr>
		<tr height="43">
			<td height="43" style="height:43px;width:119px;">Flow cytometry strainers</td>
			<td style="width:124px;">BD Biosciences</td>
			<td style="width:135px;">340626</td>
			<td style="width:143px;"></td>
		</tr>
		<tr height="43">
			<td height="43" style="height:43px;width:119px;">Falcon cell strainers</td>
			<td style="width:124px;">Thermo Fisher Scientific</td>
			<td style="width:135px;">352340</td>
			<td style="width:143px;"></td>
		</tr>
		<tr height="43">
			<td height="43" style="height:43px;width:119px;">Flow cytometry tubes</td>
			<td style="width:124px;">Falcon</td>
			<td style="width:135px;">352052</td>
			<td style="width:143px;">5 ml Polystyrene Round-Bottom Tube</td>
		</tr>
		<tr height="43">
			<td height="43" style="height:43px;width:119px;">Centrifuge tubes</td>
			<td style="width:124px;">Corning centristar</td>
			<td style="width:135px;">430791</td>
			<td style="width:143px;"></td>
		</tr>
		<tr height="43">
			<td height="43" style="height:43px;width:119px;">Water bath</td>
			<td style="width:124px;">Memmert GmbH + Co. KG</td>
			<td style="width:135px;">WNE 7</td>
			<td style="width:143px;">37&#186;C</td>
		</tr>
		<tr height="106">
			<td height="106" style="height:106px;width:119px;">Fixation/Permeabilization Solution or Permeabilization/Wash Buffer</td>
			<td style="width:124px;">BD Biosciences</td>
			<td style="width:135px;">554714</td>
			<td style="width:143px;"></td>
		</tr>
		<tr height="43">
			<td height="43" style="height:43px;width:119px;">Rompum (Xylazine)</td>
			<td style="width:124px;">Bayer</td>
			<td style="width:135px;"></td>
			<td style="width:143px;">Or equivalent</td>
		</tr>
		<tr height="43">
			<td height="43" style="height:43px;width:119px;">Ketalar (Ketamine)</td>
			<td style="width:124px;">Pfizer</td>
			<td style="width:135px;"></td>
			<td style="width:143px;">Or equivalent</td>
		</tr>
		<tr height="43">
			<td height="43" style="height:43px;width:119px;">Hanks&#8217; balanced salt solution</td>
			<td style="width:124px;">Sigma-Aldrich</td>
			<td style="width:135px;">H8264-500ML</td>
			<td style="width:143px;"></td>
		</tr>
		<tr height="22">
			<td height="22" style="height:22px;width:119px;">Saline solution</td>
			<td style="width:124px;">Braun</td>
			<td style="width:135px;">622415</td>
			<td style="width:143px;"></td>
		</tr>
		<tr height="64">
			<td height="64" style="height:64px;width:119px;">Anti-CD45 (clone:OX-1) APC-Cy7</td>
			<td style="width:124px;">Biolegend</td>
			<td style="width:135px;">202216</td>
			<td style="width:143px;">Diluted 1:100</td>
		</tr>
		<tr height="43">
			<td height="43" style="height:43px;width:119px;">Anti-CD68 (clone: ED1) FITC</td>
			<td style="width:124px;">Bio-RAD</td>
			<td style="width:135px;">MCA341F</td>
			<td style="width:143px;">Diluted 35:1000</td>
		</tr>
		<tr height="43">
			<td height="43" style="height:43px;width:119px;">anti-CD86 (clone: 24F) PE</td>
			<td style="width:124px;">Biolegend</td>
			<td style="width:135px;">200307</td>
			<td style="width:143px;">Diluted 35:1000</td>
		</tr>
		<tr height="64">
			<td height="64" style="height:64px;width:119px;">anti-CD163 (clone: ED2) Alexa Fluor 647</td>
			<td style="width:124px;">Bio-RAD</td>
			<td style="width:135px;">MCA342R</td>
			<td style="width:143px;">Diluted 4:100</td>
		</tr>
		<tr height="22">
			<td height="22" style="height:22px;width:119px;">Live/dead stain&#160;</td>
			<td style="width:124px;">Molecular Probes</td>
			<td style="width:135px;">L34955</td>
			<td style="width:143px;">Diluted 3:1000</td>
		</tr>
	</tbody>
</table>

phenotypic characterization of macrophages from rat kidney by flow cytometry

There is increasing evidence suggesting the important role of inflammation and, subsequently, macrophages in the development and progression of renal disease. Macrophages are heterogeneous cells that have been implicated in kidney injury. Macrophages may be classified into two different phenotypes: classically activated macrophages (M1 macrophages), that release pro-inflammatory cytokines and promote fibrosis; and alternatively activated macrophages (M2 macrophages) that are associated with immunoregulatory and tissue-remodeling functions. These macrophage phenotypes need to be discriminated and analyzed to determine their contribution to renal injury. However, there are scarce studies reporting consistent phenotypic and functional information about macrophage subtypes in inflammatory renal disease models, especially in rats. This fact may be related to the limited macrophage markers used in rats, contrary to mice. Therefore, novel strategies are necessary to quantify and characterize the renal content of these infiltrating cells in a reliable way. This manuscript details a protocol for kidney digestion and further phenotypic and quantitative analysis of macrophages from rat kidneys by flow cytometry. Briefly, kidneys were incubated with collagenase and total macrophages were identified according to the dual presence of CD45 (leukocytes common antigen) and CD68 (PAN macrophage marker) in live cells.This was followed by surface staining of CD86 (M1 marker) and CD163 (M2 marker). Rat peritoneal macrophages were used as positive control for macrophage marker detection by flow cytometry. Our protocol resulted in low cellular mortality and allowed characterization of different intracellular and surface protein markers, thus limiting the loss of cellular integrity observed in other protocols. Moreover, this procedure allows the use of macrophages for further techniques, including cell sorting and mRNA or protein expression studies, among others.

We analyzed macrophage heterogeneity in an inflammatory experimental model of renal injury associated with increased presence of infiltrating macrophages in the kidney. In this model, renal damage was induced by administration of aldosterone (1 mg-1kg-1day) plus salt (NaCl 1%) in drinking water for 3 weeks in Wistar rats, as previously reported12.
The schedule of our experiments is shown in <stro...

Watch this Scientific Journal Video about Phenotypic Characterization of Macrophages from Rat Kidney by Flow Cytometry at JoVE.com

Phenotypic Characterization of Macrophages from Rat Kidney by Flow Cytometry

This manuscript describes a detailed protocol for phenotypic and quantitative analysis of resident macrophages from rat kidneys by flow cytometry. The resulting stained cells can be also used for other applications, including cell sorting, gene expression analysis or functional studies, thus increasing the information obtained in the experimental model.

There is increasing evidence suggesting the important role of inflammation and, subsequently, macrophages in the development and progression of renal ...

The overall goal of this procedure is to quantify and characterize resident macrophages from rat kidneys by flow cytometry.This method can have answer key question in the fluidity such what is the contribution of each macraphage of type in kidney injury.The main advantage of this technique is that it allows the kidney catheterization of differing protein marker.Thus, limiting the of cellular integrity of Demonstrating the procedure will be Elena Olivares, A.P.A.S.D.student from the Complutense University and Melania Guerrero, A.P.A.S.D.student from For kidney perfusion and extraction, begin by pinching a small fold of skin to confirm that the rat has reached the appropriate level of sedation.And cover the eyes with Vet ointment.Place the animal on a surgical table in the supine position.And soak the abdomen with 70%ethanol.Next, make a central incision through the abdominal skin and peritoneum from the pubis to the ribcage to expose the pleural and abdominal cavities.Use the perfusion system to inject 0.9%saline solution into the abdominal aorta to flush the kidneys.Cutting the aorta at the abdomen to help release the blood.When all of the blood has been removed from the kidneys, sever the renal hilum.Then press the edge of each kidney to carefully decapsulate the organs.And transfer the extracted kidneys into fresh H.B.S.S.To generate a single kidney cell suspension, use scissors to cut half of one kidney into small fragments.Transfer the tissue pieces into a 1.5 mL tube and add 1 mL of freshly prepared collagenase to the tube for a 30 minute incubation at 37

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