The authors thank the support of the Zell Family Foundation. We recognize support from the Northwestern Memorial Foundation Dixon Translational Research Grants Initiative, the American Society of Transplant Surgeon&#8217;s Faculty Development Grant, and a Research Grant for the Young Investigator from the National Kidney Foundation of Illinois. We acknowledge support from the Robert R. McCormick Foundation. This work was also supported by NIDDK K08 DK10175 to J.A.W. Imaging and histology cores used for this research is supported by the Mouse Histology and Phenotyping Laboratory, Electron Probe Instrumentation Center (EPIC), and Simpson Querrey Institute Equipment Core at Northwestern University, and a Cancer Center Support Grant (NCI CA060553). The authors would like to acknowledge the Northwestern University Microsurgery Core for rodent kidney procurements. Evaluation of renal tubular epithelia morphology following recellularization conducted in the Fluorescence Microscopy Shared Resource supported by P30 CA118100.

ETHICS STATEMENT:All procedures involving animals were performed according to guidelines approved by the Institutional Animal Care and Use Committee of Northwestern University.
1. Kidney Decellularization
<ol>
	<li>Prepare decellularization solutions. Prepare the following volumes of reagents for each kidney to be decellularized, plus one additional volume (e.g., for 4 kidneys, prepare 5,000 ml&#160;Triton X-100 for step 1.1.3):
	<ol>
		<li>Prepare 500 ml&#160;reverse osmosis water ...

<ol>
	<li>Uzarski, J. S., Xia, Y., Belmonte, J. C., Wertheim, J. A. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=New+strategies+in+kidney+regeneration+and+tissue+engineering.">New strategies in kidney regeneration and tissue engineering.</a> Current opinion in nephrology and hypertension. 23, 399-405 (2014).</li><li>Soto-Gutierrez, A., Wertheim, J. A., Ott, H. C., Gilbert, T. W. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Perspectives+on+whole-organ+assembly:+moving+toward+transplantation+on+demand.">Perspectives on whole-organ assembly: moving toward transplantation on demand.</a> J Clin Invest. 122, 3817-3823 (2012).</li><li>Badylak, S. F. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Decellularized+allogeneic+and+xenogeneic+tissue+as+a+bioscaffold+for+regenerative+medicine:+factors+that+influence+the+host+response.">Decellularized allogeneic and xenogeneic tissue as a bioscaffold for regenerative medicine: factors that influence the host response.</a> Ann Biomed Eng. 42, 1517-1527 (2014).</li><li>Miner, J. H. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Renal+basement+membrane+components.">Renal basement membrane components.</a> Kidney Int. 56, 2016-2024 (1999).</li><li>Nichol, J. W., Khademhosseini, A. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Modular+Tissue+Engineering:+Engineering+Biological+Tissues+from+the+Bottom+Up.">Modular Tissue Engineering: Engineering Biological Tissues from the Bottom Up.</a> Soft matter. 5, 1312-1319 (2009).</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> Nat Med. 14, 213-221 (2008).</li><li>Caralt, 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=Optimization+and+critical+evaluation+of+decellularization+strategies+to+develop+renal+extracellular+matrix+scaffolds+as+biological+templates+for+organ+engineering+and+transplantation.">Optimization and critical evaluation of decellularization strategies to develop renal extracellular matrix scaffolds as biological templates for organ engineering and transplantation.</a> American Journal of Transplantation. 15, 64-75 (2015).</li><li>Badylak, S. F., Taylor, D., Uygun, K. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Whole-organ+tissue+engineering:+decellularization+and+recellularization+of+three-dimensional+matrix+scaffolds.">Whole-organ tissue engineering: decellularization and recellularization of three-dimensional matrix scaffolds.</a> Annu Rev Biomed Eng. 13, 27-53 (2011).</li><li>Orlando, G., 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=Discarded+human+kidneys+as+a+source+of+ECM+scaffold+for+kidney+regeneration+technologies.">Discarded human kidneys as a source of ECM scaffold for kidney regeneration technologies.</a> Biomaterials. 34, 5915-5925 (2013).</li><li>Sullivan, D. 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=Decellularization+methods+of+porcine+kidneys+for+whole+organ+engineering+using+a+high-throughput+system.">Decellularization methods of porcine kidneys for whole organ engineering using a high-throughput system.</a> Biomaterials. 33, 7756-7764 (2012).</li><li>Vishwakarma, S. K., et al. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Preparation+of+natural+three-dimensional+goat+kidney+scaffold+for+the+development+of+bioartificial+organ.">Preparation of natural three-dimensional goat kidney scaffold for the development of bioartificial organ.</a> Indian journal of nephrology. 24, 372-375 (2014).</li><li>Ross, 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=Embryonic+stem+cells+proliferate+and+differentiate+when+seeded+into+kidney+scaffolds.">Embryonic stem cells proliferate and differentiate when seeded into kidney scaffolds.</a> J Am Soc Nephrol. 20, 2338-2347 (2009).</li><li>Song, J. 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=Regeneration+and+experimental+orthotopic+transplantation+of+a+bioengineered+kidney.">Regeneration and experimental orthotopic transplantation of a bioengineered kidney.</a> Nat Med. 19, 646-651 (2013).</li><li>Bonandrini, B., et al. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Recellularization+of+well-preserved+acellular+kidney+scaffold+using+embryonic+stem+cells.">Recellularization of well-preserved acellular kidney scaffold using embryonic stem cells.</a> Tissue Eng Part A. 20, 1486-1498 (2014).</li><li>Burgkart, 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=Decellularized+kidney+matrix+for+perfused+bone+engineering.">Decellularized kidney matrix for perfused bone engineering.</a> Tissue Eng Part C Methods.2. 20, 553-561 (2014).</li><li>Ross, 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=Mouse+stem+cells+seeded+into+decellularized+rat+kidney+scaffolds+endothelialize+and+remodel+basement+membranes.">Mouse stem cells seeded into decellularized rat kidney scaffolds endothelialize and remodel basement membranes.</a> Organogenesis. 8, 49-55 (2012).</li><li>Uzarski, J. 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=Dual-purpose+bioreactors+to+monitor+non-invasive+physical+and+biochemical+markers+of+kidney+and+liver+scaffold+recellularization.">Dual-purpose bioreactors to monitor non-invasive physical and biochemical markers of kidney and liver scaffold recellularization.</a> Tissue Eng Part C Methods. , (2015).</li><li>Brien, J., Wilson, I., Orton, T., Pognan, F. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Investigation+of+the+Alamar+Blue+(resazurin)+fluorescent+dye+for+the+assessment+of+mammalian+cell+cytotoxicity.">Investigation of the Alamar Blue (resazurin) fluorescent dye for the assessment of mammalian cell cytotoxicity.</a> European journal of biochemistry / FEBS. 267, 5421-5426 (2000).</li><li>Loghman-Adham, M., Nauli, S. M., Soto, C. E., Kariuki, B., Zhou, J. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Immortalized+epithelial+cells+from+human+autosomal+dominant+polycystic+kidney+cysts.+American+journal+of+physiology.">Immortalized epithelial cells from human autosomal dominant polycystic kidney cysts. American journal of physiology.</a> Renal physiology. 285, F397-F412 (2003).</li></ol>

The described decellularization protocol consistently produces a completely acellular kidney ECM that serves as a 3D template for culture of human renal cortical tubular epithelial cells (both proximal and distal tubule-derived), in addition to vascular endothelial cells7,17. The cannulated renal vasculature serves as the key feature for uniform delivery of reagents and cells throughout the scaffold within a bioreactor set-up, thus enabling the perfusion decellularization, cell seeding, long-term perfusion cul...

An erratum was issued for <a href="http://www.jove.com/video/53271/epithelial-cell-repopulation-preparation-rodent-extracellular-matrix">Epithelial Cell Repopulation and Preparation of Rodent Extracellular Matrix Scaffolds for Renal Tissue Development</a>.
The human RCTEC/RCTE cell stocks used here and in Caralt et al., 2015, Uzarski et al., 2015 were originally provided by Dr. Loghman-Adham (then at St. Louis University) to co-author Dr. Wandinger-Ness (University of New Mexico) through an MTA in 2001. The SV40 immortalized human RCTEC/RCTE cells were characterized as being of distal tubule cell line as detailed in Loghman-Adham et al., 2003. On the basis of recent short tandem repeat (STR) DNA sequencing (Performed by IDEXX BioResearch) of the earliest passages of the RCTEC/RCTE cell stocks it became evident the cells were of mixed lineage. Further analyses of PCR products using QIAxcel capillary electrophoresis demonstrated the presence of a canine product. The product was sequenced and established to be of canine origin. A set of canine specific STR markers were compared to the sample and showed that the sample had a genetic profile with 92% identity to the MDCK cell line.&#160; Later cell stocks that were used in the present publication were STR profiled and showed drift to 100% MDCK lineage. Despite being of canine origin, rather than human as was previously thought, MDCK is similarly a distal tubule epithelial cell line. For this reason, previous interpretation and conclusions drawn using these cells here and in Caralt et al., 2015, Uzarski et al., 2015 remain sound, but for purposes of rigor, reproducibility and experimental validation by others we report on this misidentification. This information will also be reported for listing on the International Cell Line Authentication Committee (ICLAC) database (http://iclac.org).

Erratum: Epithelial Cell Repopulation and Preparation of Rodent Extracellular Matrix Scaffolds for Renal Tissue Development

As the number of patients suffering from end-stage renal failure continues to increase, there is a severe and growing shortage in the number of donor kidneys available for transplantation. The inability to meet the demand of a continually rising number of candidates wait-listed for kidney transplantation has prompted research in kidney organ engineering with the ultimate goal of developing customized, implantable kidney grafts on demand1,2. Building functioning kidney tissue from a patient&#8217;s own cells would eliminate the need for lifelong immunosuppression, decrease the amount of time patients spend on dialysis waiting for a kidney transplant, and extend life-saving transplantation to more patients with chronic kidney disease.
The first step toward bioengineering a kidney tissue using patient-derived cells is to develop a scaffold that serves as a supportive substrate for renal parenchyma (e.g. tubular epithelial), stroma fibroblast, and vascular cell growth. Biomaterial scaffolds derived from natural organ extracellular matrices (ECMs) have several characteristics that make them desirable for use in tissue engineering, including their natural biological composition; appropriate macro- and microstructure to endow physiological function; and cellular biocompatibility, promoting cell adhesion, migration, and constructive tissue remodeling3. A promising method to produce scaffolds for renal tissue regeneration is through decellularization of allogeneic or xenogeneic kidneys that preserve much of the complex natural protein composition of the kidney ECM4, retain the inherent architectural intricacy of the organ, and overcome the difficulty associated with bottom-up engineering of thick cellularized tissues by providing a vascular supply to developing cells after scaffold recellularization5.
Perfusion decellularization is a process in which detergents, enzymes, or other cell-disrupting solutions are uniformly delivered through the vascular network of the organ6. This strategy has been established as an efficient process to derive acellular organ-based ECM scaffolds as three-dimensional (3D), biological templates for whole-organ engineering6-8, as evidenced by the development of acellular renal templates from discarded human kidneys9 and xenogeneic kidneys obtained from large-animal (e.g. pig10, goat11) and rodent sources12. In particular, the use of small animal models such as rodents requires fewer cells and culture media, which is especially helpful for organ recellularization studies in which cell numbers are usually limited, as is the case with stem cell-derived tissues. The goal of the described decellularization protocol is to produce an acellular renal ECM that can be used as a 3D scaffolding system for regeneration of kidney structures, including nephron tubules that are repopulated in the present example with human renal cortical tubular epithelial (RCTE) cells. We previously described our rigorous evaluation of an optimal, detergent-based rat kidney decellularization protocol7, which is more rapid (approximately one day) than other methods previously reported (Ross et al.- 5 days12, Song et al.- 4.5 days13), and exposes the organ to a considerably lower concentration (0.1%) of the denaturant sodium dodecyl sulfate (SDS) during decellularization than prior reports12-15.
A limited number of studies have described the use of rodent kidneys for decellularization and subsequent use as a 3D scaffold for cellular repopulation (reviewed elsewhere1)12-16. In this protocol, we provide a detailed description of our previously established, optimal decellularization strategy for producing acellular kidney scaffolds from Sprague Dawley rat kidneys7. Using custom-designed perfusion bioreactors capable of dual seeding and maintenance perfusion culture17, we recellularize the acellular kidney scaffolds with human RCTE cells, which consistently repopulate the tubular component in these decellularized matrices, proliferate, and survive in perfusion culture for over a week. We further demonstrate our use of the resazurin perfusion assay &#8211; an inexpensive, non-cytotoxic, and non-invasive metabolic assessment previously used for cytotoxicity studies17&#8211; to provide an indication of cell viability and proliferation within the recellularized kidneys over time7.

<table border="0" cellpadding="0" cellspacing="0">
	<tbody>
		<tr>
			<td>Reagents</td>
			<td></td>
			<td></td>
			<td></td>
		</tr>
		<tr>
			<td>TRITON X-100, Proteomics Grade, AMRESCO</td>
			<td>VWR</td>
			<td>M143-4L</td>
			<td></td>
		</tr>
		<tr>
			<td>Sodium dodecyl sulfate solution, BioUltra, for molecular biology, 20% in H2O</td>
			<td>Sigma-Aldrich</td>
			<td>05030</td>
			<td></td>
		</tr>
		<tr>
			<td>Peracetic acid solution, purum, ~39% in acetic acid (RT)</td>
			<td>Sigma-Aldrich</td>
			<td>77240</td>
			<td>Peracetic is flammable and corrosive. Prepare within a fume hood using appropriate personal protective equipment (e.g. gloves, goggles).</td>
		</tr>
		<tr>
			<td>200 proof ethanol</td>
			<td>VWR</td>
			<td>V1001TP</td>
			<td></td>
		</tr>
		<tr>
			<td>Sigmacote, siliconizing reagent for glass and other surfaces</td>
			<td>Sigma-Aldrich</td>
			<td>SL2</td>
			<td>For treatment of bioreactor reservoirs. Referred to in text as siliconizing reagent.</td>
		</tr>
		<tr>
			<td>DMEM/F12 media</td>
			<td>Life Technologies</td>
			<td>11320-033</td>
			<td></td>
		</tr>
		<tr>
			<td>Corning cellgro Fetal Bovine Serum Premium, Mediatech</td>
			<td>Corning</td>
			<td>35-010-CV</td>
			<td></td>
		</tr>
		<tr>
			<td>Penicillin-Streptomycin Solution, 100X 10,000 I.U. Penicillin 10,000 &#181;g/mL Streptomycin</td>
			<td>Corning</td>
			<td>30-002-CI</td>
			<td></td>
		</tr>
		<tr>
			<td>TrypLE Express (1X), Phenol Red</td>
			<td>Life Technologies</td>
			<td>12605-028</td>
			<td>Referred to in text as cell dissociating enzyme.</td>
		</tr>
		<tr>
			<td>Trypan Blue Stain (0.4%)</td>
			<td>Life Technologies</td>
			<td>15250-061</td>
			<td></td>
		</tr>
		<tr>
			<td>Resazurin sodium salt</td>
			<td>Sigma-Aldrich</td>
			<td>R7017</td>
			<td></td>
		</tr>
		<tr>
			<td>Equipment:</td>
			<td></td>
			<td></td>
			<td></td>
		</tr>
		<tr>
			<td>Masterflex L/S Digital Drive, 600 RPM, 115/230 VAC</td>
			<td>Cole-Parmer</td>
			<td>EW-07522-20</td>
			<td></td>
		</tr>
		<tr>
			<td>Masterflex L/S large cartridges for 07519-05 and -06 pump heads.</td>
			<td>Cole-Parmer</td>
			<td>EW-07519-70</td>
			<td>Referred to in text as large pump cartridge.</td>
		</tr>
		<tr>
			<td>Masterflex L/S 8-channel, 4-roller cartridge pump head.</td>
			<td>Cole-Parmer</td>
			<td>EW-07519-06</td>
			<td></td>
		</tr>
		<tr>
			<td>Straight 6&#34; specimen forceps, serrated</td>
			<td>VWR</td>
			<td>82027-438</td>
			<td></td>
		</tr>
		<tr>
			<td>*Kidney perfusion bioreactor</td>
			<td>WilMad Labglass</td>
			<td>*Custom designs</td>
			<td>Bioreactors are produced as described by WilMad Labglass. The designs have been described in depth in a previous publication.</td>
		</tr>
		<tr>
			<td>Perfusion Circuit Components</td>
			<td></td>
			<td></td>
			<td></td>
		</tr>
		<tr>
			<td>24 G x 0.75 in. BD Insyte Autoguard shielded IV catheter (0.7 mm x 19 mm) made of BD Vialon biomaterial. Has notched needle. (50/sp, 200/ca)</td>
			<td>BD Biosciences</td>
			<td>381412</td>
			<td>Referred to in text as 24 gauge catheter.</td>
		</tr>
		<tr>
			<td>Masterflex PharMed BPT Tubing, L/S #14, 25&#39;</td>
			<td>Cole-Parmer</td>
			<td>HV-06508-14</td>
			<td>Referred to in text as peristaltic pump tubing.</td>
		</tr>
		<tr>
			<td>Peroxide-Cured Silicone Tubing, 1/16&#34;id X 1/8&#34;OD, 25 Ft/pack</td>
			<td>Cole-Parmer</td>
			<td>HV-06411-62</td>
			<td>Referred to in text as 1/16&#34; ID silicone rubber tubing.</td>
		</tr>
		<tr>
			<td>Masterflex platinum-cured silicone tubing, L/S 14, 25 ft.</td>
			<td>Cole-Parmer</td>
			<td>HV-96410-14</td>
			<td>Referred to in text as thick-walled 1/16&#34; ID silicone rubber tubing.</td>
		</tr>
		<tr>
			<td>VWR Silicone Tubing, 1/4&#34; ID x 0.5&#34; OD</td>
			<td>VWR</td>
			<td>89068-484</td>
			<td></td>
		</tr>
		<tr>
			<td>Acro 50 Vent Filters, Pall Life Sciences</td>
			<td>VWR</td>
			<td>28143-558</td>
			<td>Referred to in text as 0.2 micron vent filter.</td>
		</tr>
		<tr>
			<td>Cole-Parmer Luer Adapters, Male Luer Lock to 1/8&#34; ID, Nylon, 25/Pk</td>
			<td>Cole-Parmer</td>
			<td>T-45505-11</td>
			<td>Referred to in text as male Luer lock to 1/8&#34; barbed adapter.</td>
		</tr>
		<tr>
			<td>Cole-Parmer Luer Accessory, Male Luer Plug, Nylon, 25/Pk</td>
			<td>Cole-Parmer</td>
			<td>EW-45505-58</td>
			<td></td>
		</tr>
		<tr>
			<td>Female luer x female luer adapter, Nylon, 25/pk</td>
			<td>Cole-Parmer</td>
			<td>EW-45502-22</td>
			<td>Referred to in text as female Luer x female Luer adapter.</td>
		</tr>
		<tr>
			<td>Cole-Parmer Luer Accessory, Female Luer Cap, Nylon, 25/Pk</td>
			<td>Cole-Parmer</td>
			<td>EW-45502-28</td>
			<td></td>
		</tr>
		<tr>
			<td>Smiths Medical Large Bore Hi-Flo Stopcocks # MX4311L - 3-Way Hi-Flo Stopcock with Extended Male Luer Lock, Non-DEHP Formulation, Latex Free (LF), Lipid Resistant, Non-PVD, 50/cs</td>
			<td>Careforde Healthcare</td>
			<td>10254821</td>
			<td>Smiths Medical (vendor) catalogue number is #MX4311L.</td>
		</tr>
		<tr>
			<td>Other Components</td>
			<td></td>
			<td></td>
			<td></td>
		</tr>
		<tr>
			<td>5 mL BD Luer-Lok disposable syringe with BD Luer-Lok&#8482; tip.</td>
			<td>BD Biosciences</td>
			<td>309646</td>
			<td></td>
		</tr>
		<tr>
			<td>35 mm x 10 mm Easy Grip Culture Dish</td>
			<td>BD Biosciences</td>
			<td>353001</td>
			<td>Used to draw cell suspension into syringe for cell seeding.</td>
		</tr>
	</tbody>
</table>

epithelial cell repopulation and preparation of rodent extracellular matrix scaffolds for renal tissue development

This protocol details the generation of acellular, yet biofunctional, renal extracellular matrix (ECM) scaffolds that are useful as small-scale model substrates for organ-scale tissue development. Sprague Dawley rat kidneys are cannulated by inserting a catheter into the renal artery and perfused with a series of low-concentration detergents (Triton X-100 and sodium dodecyl sulfate (SDS)) over 26 hr to derive intact, whole-kidney scaffolds with intact perfusable vasculature, glomeruli, and renal tubules. Following decellularization, the renal scaffold is placed inside a custom-designed perfusion bioreactor vessel, and the catheterized renal artery is connected to a perfusion circuit consisting of: a peristaltic pump; tubing; and optional probes for pH, dissolved oxygen, and pressure. After sterilizing the scaffold with peracetic acid and ethanol, and balancing the pH (7.4), the kidney scaffold is prepared for seeding via perfusion of culture medium within a large-capacity incubator maintained at 37 &#176;C and 5% CO2. Forty million renal cortical tubular epithelial (RCTE) cells are injected through the renal artery, and rapidly perfused through the scaffold under high flow (25 ml/min) and pressure (~230 mmHg) for 15 min before reducing the flow to a physiological rate (4 ml/min). RCTE cells primarily populate the tubular ECM niche within the renal cortex, proliferate, and form tubular epithelial structures over seven days of perfusion culture. A 44 &#181;M resazurin solution in culture medium is perfused through the kidney for 1 hr during medium exchanges to provide a fluorometric, redox-based metabolic assessment of cell viability and proliferation during tubulogenesis. The kidney perfusion bioreactor permits non-invasive sampling of medium for biochemical assessment, and multiple inlet ports allow alternative retrograde seeding through the renal vein or ureter. These protocols can be used to recellularize kidney scaffolds with a variety of cell types, including vascular endothelial, tubular epithelial, and stromal fibroblasts, for rapid evaluation within this system.

Kidneys sequentially perfused with water and dilute detergent solutions (1% Triton X-100, 0.1% SDS) according to a previously established, optimal decellularization protocol (see Figure 1A, B)7, become progressively more transparent over a 26 hr period, as shown in Figure 2A. The resulting acellular kidney scaffold is devoid of cells and retains a cohesive renal ECM supported by an intact renal capsule, which is undamaged following the perfusion protocol. By the final detergen...

Watch this Scientific Journal Video about Epithelial Cell Repopulation and Preparation of Rodent Extracellular Matrix Scaffolds for Renal Tissue Development at JoVE.com

Epithelial Cell Repopulation and Preparation of Rodent Extracellular Matrix Scaffolds for Renal Tissue Development

This protocol describes decellularization of Sprague Dawley rat kidneys by antegrade perfusion of detergents through the vasculature, producing acellular renal extracellular matrices that serve as templates for repopulation with human renal epithelial cells. Recellularization and use of the resazurin perfusion assay to monitor growth is performed within specially-designed perfusion bioreactors.

This protocol details the generation of acellular, yet biofunctional, renal extracellular matrix (ECM) scaffolds that are useful as small-scale model ...

epithelial-cell-repopulation-preparation-rodent-extracellular-matrix

Research

JoVE Journal

Bioengineering

15.9K visualizações.  Northwestern University. This protocol describes decellularization of Sprague Dawley rat kidneys by antegrade perfusion of detergents through the vasculature, producing acellular renal extracellular matrices that serve as templates for repopulation with human renal epithelial cells. Recellularization and use of the resazurin perfusion assay to monitor growth is performed within specially-designed perfusion bioreactors.