We thank Prof. Ivana Novak and Dr. Nynne Meyn Christensen (Centre for Advanced Bioimaging (CAB), University of Copenhagen) for providing microscope access. This work was supported by the European Research Council (ERC-2015-CoG-682881-MATRICAN; AEM-G, OW, RR and JTE); a PhD fellowship from the Lundbeck Foundation (R286-2018-621; MR); the Swedish Research Council (2017-03389; CDM); the Swedish Cancer Society, Cancerfonden (CAN 2016/783, 19 0632 Pj, and 190007; CDM); German Cancer Aid (Deutsche Krebshilfe; RR); and the Danish Cancer Society (R204-A12454; RR).&#160;

All procedures included here have been reviewed and approved by the ethical committee regulating experimental medicine in the University of Copenhagen and agree with Danish and European legislation. To demonstrate this protocol, we have used female BALB/cJ mice of 8-12 weeks of age and an MMTV-PyMT female mouse of 11 weeks of age.
NOTE: Avoiding bacterial contamination of the decellularized ECM scaffold gives the best imaging outcome and allows long-term sample storage. It is therefore importa...

<ol>
	<li>Hynes, R. O. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Extracellular+matrix:+not+just+pretty+fibrils.">Extracellular matrix: not just pretty fibrils.</a> Science. 326, 1216-1219 (2009).</li><li>Mayorca-Guiliani, A. E., 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=ISDoT:+in+situ+decellularization+of+tissues+for+high-resolution+imaging+and+proteomic+analysis+of+native+extracellular+matrix.">ISDoT: in situ decellularization of tissues for high-resolution imaging and proteomic analysis of native extracellular matrix.</a> Nature Medicine. 23, 890-898 (2017).</li><li>Mayorca-Guiliani, A. E., 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=Decellularization+and+antibody+staining+of+mouse+tissues+to+map+native+extracellular+matrix+structures+in+3D.">Decellularization and antibody staining of mouse tissues to map native extracellular matrix structures in 3D.</a> Nature Protocols. 14, 3395-3425 (2019).</li><li>White, L. J., 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=The+impact+of+detergents+on+the+tissue+decellularization+process:+A+TOF-sims+study.">The impact of detergents on the tissue decellularization process: A TOF-sims study.</a> Acta Biomaterialia. 50, 207-219 (2017).</li><li>Ott, H. 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=Perfusion-decellularized+matrix:+using+nature's+platform+to+engineer+a+bioartificial+heart.">Perfusion-decellularized matrix: using nature's platform to engineer a bioartificial heart.</a> Nature Medicine. 14, 213-221 (2008).</li><li>Uygun, B. E., 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=Organ+re-engineering+through+development+of+a+transplantable+recellularized+liver+graft+using+decellularized+liver+matrix.">Organ re-engineering through development of a transplantable recellularized liver graft using decellularized liver matrix.</a> Nature Medicine. 16, 814-820 (2010).</li><li>Susaki, E. 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=Advanced+CUBIC+protocols+for+whole-brain+and+whole-body+clearing+and+imaging.">Advanced CUBIC protocols for whole-brain and whole-body clearing and imaging.</a> Nature Protocols. 10, 1709-1727 (2015).</li><li>Tomer, R., Ye, L., Hsueh, B., Deisseroth, K. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Advanced+CLARITY+for+rapid+and+high-resolution+imaging+of+intact+tissues.">Advanced CLARITY for rapid and high-resolution imaging of intact tissues.</a> Nature Protocols. 9, 1682-1697 (2014).</li><li>Erturk, 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=Three-dimensional+imaging+of+solvent-cleared+organs+using+3DISCO.">Three-dimensional imaging of solvent-cleared organs using 3DISCO.</a> Nature Protocols. 7, 1983-1995 (2012).</li><li>Wershof, E., et al. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=A+FIJI+Macro+for+quantifying+pattern+in+extracellular+matrix.">A FIJI Macro for quantifying pattern in extracellular matrix.</a> BioRxiv. , (2019).</li></ol>

Decellularization techniques based on tissue agitation alter ECM structure, making them unsuitable for ECM structure analysis4. Perfusion decellularization, using an anatomical route such as the aorta of the trachea, allows to reach the capillary bed, or terminal alveoli, and facilitates the delivery of decellularizing agents throughout the organ. The use of zwitterionic, anionic and non-ionic detergents to decellularize tissue is reported4,5</s...

The ECM is a three-dimensional network made of proteins and glycans that accommodates all cells in a multicellular organism, giving organs their shape and regulating cell behavior throughout life1. From egg fertilization onwards, cells build and remodel the ECM, and are in turn strictly controlled by it. The purpose of this protocol is to open a way to analyze and map mouse ECM, as mice are the most used model organism in mammalian pathophysiology.
The development of this method was driven by the need to characterize and isolate metastasis-associated native ECM2. As tumors lack proper anatomical vascularization and mice are relatively small organisms, microsurgical procedures were designed to retrogradely catheterize the aorta, while isolating the circulation of the major vessel leading to a tumor (e.g., the pulmonary veins), thus focusing reagent flow and allowing tumor decellularization. This method produces ECM scaffolds with a conserved structure2 that can be immunostained and imaged, allowing ECM structure mapping in submicron detail. To carry out this protocol, it is necessary to acquire surgical and microsurgical skills (dissection, microsuturing and catheterization) that may represent a potential limitation to its use. To our knowledge, this method represents the state-of-the-art for native ECM structure imaging analysis2,3.

<table border="1" fo:keep-together.within-page="1" fo:keep-with-next.within-page="always">
	<tbody>
		<tr>
			<td>MICROSURGERY</td>
			<td></td>
			<td></td>
			<td></td>
		</tr>
		<tr>
			<td>6-0 suture, triangular section needle (Vicryl)</td>
			<td>Ethicon</td>
			<td>6301124</td>
			<td></td>
		</tr>
		<tr>
			<td>9-0 micro-suture (Safil)</td>
			<td>B Braun</td>
			<td>G1048611</td>
			<td></td>
		</tr>
		<tr>
			<td>Adson forceps</td>
			<td>Fine Science Tools</td>
			<td>11006-12</td>
			<td></td>
		</tr>
		<tr>
			<td>Adson forceps with teeth</td>
			<td>Fine Science Tools</td>
			<td>11027-12</td>
			<td></td>
		</tr>
		<tr>
			<td>Castroviejo microneedle holder</td>
			<td>Fine Science Tools</td>
			<td>no. 12061-01</td>
			<td></td>
		</tr>
		<tr>
			<td>CO2 ventilation chamber for mouse euthanasia</td>
			<td></td>
			<td></td>
			<td></td>
		</tr>
		<tr>
			<td>Deionized water (Milli-Q IQ 7000, Ultrapure lab water system)&#160;</td>
			<td>Merck</td>
			<td>ZIQ7000T0</td>
			<td></td>
		</tr>
		<tr>
			<td>Disposable polystyrene tray (~30 &#215; 50 cm)</td>
			<td></td>
			<td></td>
			<td></td>
		</tr>
		<tr>
			<td>Dissection microscope (Greenough, with two-armed gooseneck)</td>
			<td>Leica</td>
			<td>S6 D</td>
			<td></td>
		</tr>
		<tr>
			<td>Double-ended microspatula</td>
			<td>Fine Science Tools</td>
			<td>10091-12</td>
			<td></td>
		</tr>
		<tr>
			<td>Dumont microforceps (two)</td>
			<td>Fine Science Tools</td>
			<td>11252-20</td>
			<td></td>
		</tr>
		<tr>
			<td>Dumont microforceps with 45&#176; tips (two)</td>
			<td>Fine Science Tools</td>
			<td>11251-35</td>
			<td></td>
		</tr>
		<tr>
			<td>Hair clippers</td>
			<td>Oster</td>
			<td>76998-320-051</td>
			<td></td>
		</tr>
		<tr>
			<td>Halsey needle holder (with tungsten carbide jaws)</td>
			<td>Fine Science Tools</td>
			<td>12500-12</td>
			<td></td>
		</tr>
		<tr>
			<td>Intravenous 24-gauge catheter (Insyte)</td>
			<td>BD</td>
			<td>381512</td>
			<td></td>
		</tr>
		<tr>
			<td>Intravenous 26-gauge catheter (Terumo)</td>
			<td>Surflo-W</td>
			<td>SR+DM2619WX</td>
			<td></td>
		</tr>
		<tr>
			<td>Mayo scissors (tough cut, straight)</td>
			<td>Fine Science Tools</td>
			<td>14110-15</td>
			<td></td>
		</tr>
		<tr>
			<td>Microforceps with ringed tips (two)</td>
			<td>Aesculap</td>
			<td>FM571R</td>
			<td></td>
		</tr>
		<tr>
			<td>Micro-spring scissors (Vannas, curved)</td>
			<td>Fine Science Tools</td>
			<td>15001-08</td>
			<td></td>
		</tr>
		<tr>
			<td>Minicutter</td>
			<td>KLS Martin</td>
			<td>80-008-03-04</td>
			<td></td>
		</tr>
		<tr>
			<td>Molt Periostotome</td>
			<td>Aesculap</td>
			<td>D0543R</td>
			<td></td>
		</tr>
		<tr>
			<td>Needles (27 gauge; Microlance)</td>
			<td>BD</td>
			<td>21018</td>
			<td></td>
		</tr>
		<tr>
			<td>Paper towel (sterile) or surgical napkin&#160;</td>
			<td></td>
			<td></td>
			<td></td>
		</tr>
		<tr>
			<td>Serrated scissors (CeramaCut, straight)</td>
			<td>Fine Science Tools</td>
			<td>14958-09</td>
			<td></td>
		</tr>
		<tr>
			<td>Spatula (Freer-Yasargil)</td>
			<td>Aesculap</td>
			<td>OL166R</td>
			<td></td>
		</tr>
		<tr>
			<td>Syringes (1 mL; Plastipak)</td>
			<td>BD</td>
			<td>3021001</td>
			<td></td>
		</tr>
		<tr>
			<td>Syringes (10 mL; Plastipak)</td>
			<td>BD</td>
			<td>3021110</td>
			<td></td>
		</tr>
		<tr>
			<td>Tendon scissors (Walton)</td>
			<td>Fine Science Tools</td>
			<td>14077-09</td>
			<td></td>
		</tr>
		<tr>
			<td>IMMUNOSTAINING</td>
			<td></td>
			<td></td>
			<td></td>
		</tr>
		<tr>
			<td>Alexa Fluor 488 donkey anti-guinea pig IgG</td>
			<td>Thermo Fisher Scientific</td>
			<td>A-11055</td>
			<td></td>
		</tr>
		<tr>
			<td>Alexa Fluor 594 donkey anti-rabbit IgG</td>
			<td>Life Technologies</td>
			<td>A11037</td>
			<td></td>
		</tr>
		<tr>
			<td>BSA(albumin bovine fraction V, standard grade, lyophilized)&#160;</td>
			<td>Serva</td>
			<td>11930.03</td>
			<td></td>
		</tr>
		<tr>
			<td>Collagen IV polyclonal antibody (RRID: AB_2276457)&#160;</td>
			<td>Millipore</td>
			<td>AB756P</td>
			<td>Host: rabbit</td>
		</tr>
		<tr>
			<td>PBS (pH 7.4, 10&#215;, Gibco)&#160;</td>
			<td>Thermo Fisher Scientific</td>
			<td>70011044</td>
			<td>Host: goat</td>
		</tr>
		<tr>
			<td>Periostin polyclonal antibody (a kind gift from Manuel Koch. RRID:AB2801621)</td>
			<td></td>
			<td></td>
			<td>Host: guinea pig</td>
		</tr>
		<tr>
			<td>Scalpel disposable with blade no.11 (pcs. 10)</td>
			<td>VWR</td>
			<td>233-5364)</td>
			<td></td>
		</tr>
		<tr>
			<td>Serum (normal donkey serum)&#160;</td>
			<td>Jackson ImmunoResearch</td>
			<td>017-000-121</td>
			<td></td>
		</tr>
		<tr>
			<td>Tween 20</td>
			<td>Sigma-Aldrich</td>
			<td>P9416-50ML</td>
			<td></td>
		</tr>
		<tr>
			<td>IMAGING</td>
			<td></td>
			<td></td>
			<td></td>
		</tr>
		<tr>
			<td>&#160;Detectors (hybrid detector (Leica, HyD S model) and photomultiplier tubes (PMTs; )&#160;</td>
			<td>Leica</td>
			<td></td>
			<td></td>
		</tr>
		<tr>
			<td>&#160;Fluorescence light source&#160;</td>
			<td>Leica</td>
			<td>EL6000</td>
			<td></td>
		</tr>
		<tr>
			<td>&#160;Microscope (inverted multiphoton microscope)&#160;</td>
			<td>Leica</td>
			<td>SP5-X MP</td>
			<td></td>
		</tr>
		<tr>
			<td>&#160;Objective (lambda blue, 20&#215;, 0.70 numerical aperture (NA) IMM UV)&#160;</td>
			<td>Leica</td>
			<td>HCX PL APO</td>
			<td></td>
		</tr>
		<tr>
			<td>&#160;Two-photon Ti&#8211;sapphire laser (Spectra-physics, Mai Tai DeepSee model)&#160;</td>
			<td></td>
			<td></td>
			<td></td>
		</tr>
		<tr>
			<td>&#160;White-light laser (WLL)&#160;</td>
			<td>Leica</td>
			<td></td>
			<td></td>
		</tr>
		<tr>
			<td>DECELLULARIZATION</td>
			<td></td>
			<td></td>
			<td></td>
		</tr>
		<tr>
			<td>70% Ethanol (absolute alcohol 99.9%); absolute alcohol must be adjusted to 70% (vol/vol) using deionized water&#160;</td>
			<td>Plum</td>
			<td>1680766</td>
			<td></td>
		</tr>
		<tr>
			<td>Deionized water (Milli-Q IQ 7000, Ultrapure lab water system)&#160;</td>
			<td>Merck</td>
			<td>ZIQ7000T0</td>
			<td></td>
		</tr>
		<tr>
			<td>Luer-to-tubing male fittings (1/8 inch)</td>
			<td>World Precision Instruments</td>
			<td>13158-100</td>
			<td></td>
		</tr>
		<tr>
			<td>PBS (pH 7.4, 10&#215;, Gibco)&#160;</td>
			<td>Thermo Fisher Scientific</td>
			<td>70011044</td>
			<td></td>
		</tr>
		<tr>
			<td>Penicillin-streptomycin</td>
			<td>Gibco</td>
			<td>15140122</td>
			<td></td>
		</tr>
		<tr>
			<td>Peristaltic pump (with 12 channels)</td>
			<td>Ole Dich</td>
			<td>110AC(R)20G75</td>
			<td></td>
		</tr>
		<tr>
			<td>Silicone tubing (with 2-mm i.d. and 4 mm o.d.)</td>
			<td>Ole Dich</td>
			<td>31399</td>
			<td></td>
		</tr>
		<tr>
			<td>Sodium Azide</td>
			<td>Sigma-Aldrich</td>
			<td>08591-1ML-F</td>
			<td></td>
		</tr>
		<tr>
			<td>Sodium deoxycholate (DOC)</td>
			<td>Sigma-Aldrich</td>
			<td>D6750-100G</td>
			<td></td>
		</tr>
		<tr>
			<td>Sodium Dodecyl Sulphate</td>
			<td>Sigma-Aldrich</td>
			<td>L3771-500G</td>
			<td></td>
		</tr>
		<tr>
			<td>H&#38;E STAINING</td>
			<td></td>
			<td></td>
			<td></td>
		</tr>
		<tr>
			<td>4% PFA</td>
			<td>Fisher Scientific</td>
			<td>15434389</td>
			<td></td>
		</tr>
		<tr>
			<td>96% Ethanol</td>
			<td>Plum</td>
			<td>201446-5L</td>
			<td></td>
		</tr>
		<tr>
			<td>Absolute ethanol</td>
			<td>Plum</td>
			<td>201152-1L</td>
			<td></td>
		</tr>
		<tr>
			<td>Coverslips (24x50mm; 1000 pcs)</td>
			<td>Hounisen</td>
			<td>422.245</td>
			<td></td>
		</tr>
		<tr>
			<td>Cryomolds Intermediate (15 x 15 x 5 mm; 100 pcs)</td>
			<td>Tissue-Tek</td>
			<td>4566</td>
			<td></td>
		</tr>
		<tr>
			<td>Cryostat</td>
			<td>Leica</td>
			<td>CM3050S</td>
			<td></td>
		</tr>
		<tr>
			<td>DPX mounting medium</td>
			<td>Hounisen</td>
			<td>1001.0025</td>
			<td></td>
		</tr>
		<tr>
			<td>Eosin Y solution alcoholic 0.5%</td>
			<td>Sigma</td>
			<td>1024390500</td>
			<td></td>
		</tr>
		<tr>
			<td>Feather microtome blade stainless steel,C35 (50 pcs)</td>
			<td>Pfm medical</td>
			<td>207500003</td>
			<td></td>
		</tr>
		<tr>
			<td> 
			Fisherbrand Superfrost Plus slides (25 x 75 mm; 144 pcs)</td>
			<td>Thermofisher</td>
			<td>6319483</td>
			<td></td>
		</tr>
		<tr>
			<td>Mayers hematoxylin</td>
			<td>Sigma</td>
			<td>MHS32-1L</td>
			<td></td>
		</tr>
		<tr>
			<td>OCT compound</td>
			<td>VWR</td>
			<td>361603E</td>
			<td></td>
		</tr>
		<tr>
			<td>Slide scanner (Nanozoomer)</td>
			<td>Hamamatsu Photonics</td>
			<td></td>
			<td></td>
		</tr>
		<tr>
			<td>Xylene</td>
			<td>Sigma</td>
			<td>534056-4L</td>
			<td></td>
		</tr>
	</tbody>
</table>

decellularization of the murine cardiopulmonary complex

We present here a decellularization protocol for mouse heart and lungs. It produces structural ECM scaffolds that can be used to analyze ECM topology and composition. It is based on a microsurgical procedure designed to catheterize the trachea and aorta of a euthanized mouse to perfuse the heart and lungs with decellularizing agents. The decellularized cardiopulmonary complex can subsequently be immunostained to reveal the location of structural ECM proteins. The whole procedure can be completed in 4 days.
The ECM scaffolds resulting from this protocol are free of dimensional distortions. The absence of cells enables structural examination of ECM structures down to submicron resolution in 3D. This protocol can be applied to healthy and diseased tissue from mice as young as 4-weeks old, including mouse models of fibrosis and cancer, opening the way to determine ECM remodeling associated with cardiopulmonary disease.

Cardiopulmonary decellularization 
After successfully completing the protocol, the heart and lungs, as well as annex tissue such as the aortic arc, will be free of cells. Decellularization can be validated by hematoxylin-eosin staining (Figure 1) of the ECM scaffolds showing removal of the nuclei comparing to the native tissue. These scaffolds retain the dimensions of fresh organs and its insoluble ECM structure is intact<sup class="xref...

Watch this Scientific Journal Video about Decellularization of the Murine Cardiopulmonary Complex at JoVE.com

Decellularization of the Murine Cardiopulmonary Complex

This protocol aims to decellularize the heart and lungs of mice. The resulting extracellular matrix (ECM) scaffolds can be immunostained and imaged to map the location and topology of their components.

We present here a decellularization protocol for mouse heart and lungs. It produces structural ECM scaffolds that can be used to analyze ECM topology and ...

This protocol is the gateway to the extracellular matrix. It's complexity and its structure down to sub micron scale. So the key advantage of this method is that it makes it possible to obtain an extracellular matrix that retains its structural integrity thus opening the way for biochemical and anatomical analysis.Demonstrating the procedure will be, Alejandro Mayorca Gilani, Raphael Reuten and Maria Rafaeva, currently in my laboratory and Chris Madsen and who was in my laboratory and continued the work at Lund University. Begin by shaving the thorax, abdomen and back of the euthanized mouse with a hair clipper. Disinfect the area with 70%ethanol.Then pin the mouse to a polystyrene tray, extending its four end hind limbs, as well as its head and tail. Place it under the microsurgery microscope. Using a Mayo straight pattern scissors, make a cutaneous incision running from the sub mandibular region to the lower abdomen and dissect subcutaneously to expose the thoracic wall and peritoneum.Then use microsurgical scissors to cut the pectoralis major and pectoralis minor muscles along the sixth intercostal space on both sides of the thoracic wall. Cut the sternum along the previous incisions with straight pattern scissors. Then complete a sternotomy by cutting the sternum along its long axis.Elevate and pin, both sides of the thoracic wall to expose the cardiopulmonary complex. Use round tipped micro forceps to excise the thymus and surrounding adipose tissue by delicately pulling them off their attachments. And cut the esophagus with micro scissors.Separate the brachiocephalic veins and brachiocephalic artery with sharp micro forceps. Then separate the left common carotid and left subclavian arteries from the underlying tissue to facilitate ligation and cauterization. Use a microneedle holder and sharp micro forceps and a nine oh suture to place stitches above the emergence of the brachiocephalic left common carotid and left subclavian arteries, cauterize the brachiocephalic veins.Using micro scissors, open an entrance by sectioning the ligament. Introduce a 27 gauge catheter into the trachea and delicately push until trachea branches into the bronchi, taking care to not disrupt the bronchi. Using a six O suture, place three stitches around the trachea to secure the catheter.Section the mouse at the height of the 12th thoracic vertebra, the descending Aorta runs anteriorly to the spine and should be sectioned here along with the spine. Retrogradely catheterize the Aorta and push the catheter until it reaches the aortic arc. Using a suture, place four stitches around the Aorta, beginning five millimeters below the catheter tip.Connect the mouse to a pump system using silicone tubing and lower connectors. Perfuse with deionized water at 200 microliters per minute for 15 minutes. Then change the perfusion agent to 0.5%DOC, diluted in deionized water and perfuse overnight.On the next day, change the perfusion agent to 0.1%SDS diluted in deionized water, and perfuse for eight hours. Then perfuse with deionized water for 24 hours to wash away the SDS and DOC. Resect the decellularized heart and lungs by sectioning its attachments to the thorax.Store the tissue in a sterile cryo tube in deionized water with 1%penicillin streptomycin and 0.3 micromolar sodium azide at four degrees Celsius. To perform immuno staining, block the sample by incubating it in a cryo tube containing 6%donkey serum and 3%BSA overnight. Then incubate with primary antibody in 3%donkey serum in PBS for 24 hours.After the incubation wash the sample five times in PBST for one hour per wash. Incubate the sample with fluorescently conjugated secondary antibody in 3%donkey serum in PBS for 24 hours. Then repeat the washes in PBST.Add the Ionized water and store the sample at four degrees Celsius away from direct light. To image the sample, place it in a glass bottom dish and humidify it with two droplets of storing solution. Set the objective and inspect the sample using fluorescence light.Switch to computer control, turn on lasers and adjust laser intensity, pinhole aperture, detectors wavelength, gain, resolution and zoom. Set the number and step size for Z stack, then begin acquisition. Excise one lung lobe from a euthanized mouse and place it in a 10 by 10 by five millimeter cryo mold.Cover it with approximately 500 mile microliters of OCT compound and freeze it on dry ice. Maintain the sample at that temperature. Excise one decellularized lung lobe from a processed mouse, place it in a cryo mold with the largest surface area down and cover it with OCT compound.Freeze the sample on dry ice and maintain it at that temperature until otherwise required. The sample can be stored for at least 12 weeks. Use a cryostat to section frozen tissue blocks into five micrometer sections at minus 20 degrees Celsius.And place the sections on adhesive glass slides. Transfer the slides to room temperature until air dried. Briefly immerse the slides in PBS, followed by 4%paraformaldehyde in PBS for 15 minutes.Wash once in PBS, then twice in distilled water for five minutes per wash. Immerse the slides in Myer's hematoxylin solution for 10 minutes. Next, wash the slides in a Copeland jar under running distilled water for 10 minutes and immerse in eosin solution for seven minutes.Dip in xylene several times. Apply a few drops of DPX mounting medium and place a glass cover slip. Leave the slides to dry overnight under a chemical hood then scan them in a slide scanner.After successfully completing the protocol, the heart and lungs and NX tissue will be free of cells. Decellularization can be validated by hematoxylin eosin staining of the ECM scaffolds. The scaffolds retain the dimensions of of fresh organs and its insoliable ECM structure is intact.ECM scaffolds showed increased permeability and light penetrability. Using this protocol with a motorized microscope stage allows for three dimensional tiled imaging of whole mount samples at sub micron resolution. It is essential to shun flow toward the organs of interest to achieve complete uniform decellurization.The microsurgical dissection and ligation of vessels must be effective. And at the same time respect the target tissues to maintain native VCM structure. Following this procedure, the scaffolds will be enriched for structural ECM proteins and can be used for mass spectrometry or tissue engineering.This technique paves the way to high resolution mapping of the extracellular matrix.

decellularization-of-the-murine-cardiopulmonary-complex

Research

JoVE Journal

Cancer Research

2.7K vistas.  University of Copenhagen (UCPH). Este protocolo es la puerta de entrada a la matriz extracelular. Su complejidad y su estructura hasta una escala submicrométrica. Por lo tanto, la ventaja clave de este método es que permite obtener una matriz extracelular que conserva su integridad estructural, abriendo así el camino para el análisis bioquímico y anatómico.Demostrando el procedimiento estarán, Alejandro Mayorca Gilani, Raphael Reuten y Maria Rafaeva, actualmente en mi laboratorio y Chris Madsen y quien estuvo e...