Name: preparation of decellularized kidney scaffolds in rats
Uploaded: 2021-03-18T13:30:00
Description: Watch this Scientific Journal Video about Preparation of Decellularized Kidney Scaffolds in Rats at JoVE.com

This study was supported by a Biomedical Research Institute Grant from Pusan National University Hospital.

This study was approved by the administration of Pusan National University of Medicine and was conducted in accordance with ethical guidelines for the use and care of animals. (certificate no. 2017-119). Prior to any animal studies, institutional approval should be obtained. 
NOTE: All surgical and anesthetic instruments/equipment and reagents recommended for successful surgical presentation and imaging of abdominal organs are detailed in Table 1.
1. Preparation procedures ...

<ol>
	<li>Kawai, 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=Brief+report:+HLA-mismatched+renal+transplantation+without+maintenance+immunosuppression.">Brief report: HLA-mismatched renal transplantation without maintenance immunosuppression.</a> New England Journal of Medicine. 358 (4), 353-361 (2008).</li><li>Rana, D., Zreiqat, H., Benkirane-Jessel, N., Ramakrishna, S., Ramalingam, M. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Development+of+decellularized+scaffolds+for+stem+cell-driven+tissue+engineering.">Development of decellularized scaffolds for stem cell-driven tissue engineering.</a> Journal of Tissue Engineering and Regenerative Medicine. 11 (4), 942-965 (2017).</li><li>Fu, R. H., 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+recellularization+technologies+in+tissue+engineering.">Decellularization and recellularization technologies in tissue engineering.</a> Cell Transplantation. 23 (4-5), 621-630 (2014).</li><li>Hopkinson, 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=Optimization+of+amniotic+membrane+(AM)+denuding+for+tissue+engineering.">Optimization of amniotic membrane (AM) denuding for tissue engineering.</a> Tissue Engineering. Part C, Methods. 14 (4), 371-381 (2008).</li><li>Shupe, T., Williams, M., Brown, A., Willenberg, B., Petersen, B. E. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Method+for+the+decellularization+of+intact+rat+liver.">Method for the decellularization of intact rat liver.</a> Organogenesis. 6 (2), 134-136 (2010).</li><li>Petersen, T. H., 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=Tissue-engineered+lungs+for+in+vivo+implantation.">Tissue-engineered lungs for in vivo implantation.</a> Science. 329 (5991), 538-541 (2010).</li><li>Fernandez-Perez, J., Ahearne, M. <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+decellularization+methods+on+extracellular+matrix+derived+hydrogels.">The impact of decellularization methods on extracellular matrix derived hydrogels.</a> Scientific Reports. 9 (1), 14933 (2019).</li><li>Naik, A., Griffin, M., Szarko, M., Butler, P. E. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Optimizing+the+decellularization+process+of+an+upper+limb+skeletal+muscle;+implications+for+muscle+tissue+engineering.">Optimizing the decellularization process of an upper limb skeletal muscle; implications for muscle tissue engineering.</a> Artificial Organs. 44 (2), 178-183 (2020).</li><li>Crapo, P. M., Gilbert, T. W., 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=An+overview+of+tissue+and+whole+organ+decellularization+processes.">An overview of tissue and whole organ decellularization processes.</a> Biomaterials. 32 (12), 3233-3243 (2011).</li><li>Mason, C., Dunnill, P. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=A+brief+definition+of+regenerative+medicine.">A brief definition of regenerative medicine.</a> Regenerative Medicine. 3 (1), 1-5 (2008).</li><li>Guyette, J. P., 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+decellularization+of+whole+organs.">Perfusion decellularization of whole organs.</a> Nature Protocols. 9 (6), 1451-1468 (2014).</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> Nature Medicine. 19 (5), 646-651 (2013).</li></ol>

Various protocols have been used for decellularization of organs and other tissues. The optimal decellularization protocol should preserve the three-dimensional architecture of the extracellular matrix (ECM). In general, such protocols consist of lysing the cell membrane by physical processing or ionic solutions, dissociating the cytoplasm and nucleus from the ECM by enzymatic processing or detergents, and then removing cellular debris from the tissue3. Physical processes include scraping, solutio...

Cell culture techniques are applied for regeneration of functional tissues and organs to replace diseased or damaged organs. Allogenic organ transplantation is currently the most common treatment for irreversible organ damage; however, this approach requires the use of immunosuppression to prevent rejection of the transplanted organ. Moreover, despite advances in transplant immunology, 20% of transplant recipients may experience acute rejection within 5 years, and within 10 years after transplantation, 40% of recipients may lose their transplanted graft or die1.
Advances in tissue engineering technologies have yielded in a new paradigm for transplantation of new organs without immune rejection using differentiated stem cells. After stem cell differentiation, a scaffold, called a synthetic extracellular matrix, is needed to facilitate the generation of three-dimensional organs and enable the new tissue to thrive within the recipient. Scaffolds from decellularized native organs have advantages, including a more effective environment for establishment of cells and enhancement of stem cell proliferation, although these mechanisms have not been fully elucidated2. In particular, the kidney is a suitable organ for scaffold generation because it has abundant circulation and a niche for stem cell establishment. Additionally, because of the complex structure of the kidney, it is difficult to artificially regenerate kidneys for organ transplantation.
In this report, we introduce a method of developing vascularized scaffolds using decellularized organs in a rat model to facilitate future animal studies for tissue engineering purposes.

<table>
	<tbody>
		<tr>
			<td>1 cc syringe (inject probes and vehicle solutions</td>
			<td>Becton Dickinson</td>
			<td>305217</td>
			<td></td>
		</tr>
		<tr>
			<td>10-0 ethilon for vessel anastomosis</td>
			<td>Ethicon</td>
			<td>9032G</td>
			<td></td>
		</tr>
		<tr>
			<td>25 gauge inch guide needle(for vascular catheters)</td>
			<td>Becton Dickinson</td>
			<td>305145</td>
			<td></td>
		</tr>
		<tr>
			<td>3-0 PDS incision closure rat</td>
			<td>Ethicon</td>
			<td>Z316H</td>
			<td></td>
		</tr>
		<tr>
			<td>3-0 Prolene incision closure rat</td>
			<td>Ethicon</td>
			<td>8832H</td>
			<td></td>
		</tr>
		<tr>
			<td>3-0 silk spool vascular access/ligation in rat</td>
			<td>Braintree Scientific</td>
			<td>SUT-S 110</td>
			<td></td>
		</tr>
		<tr>
			<td>4-0 PDS incision closure mouse</td>
			<td>Ethicon</td>
			<td>Z773D</td>
			<td></td>
		</tr>
		<tr>
			<td>4-0 Prolene incision closure mouse</td>
			<td>Ethicon</td>
			<td>8831H</td>
			<td></td>
		</tr>
		<tr>
			<td>5-0 silk spool vascular access/ligation in mouse</td>
			<td>Braintree Scientific</td>
			<td>SUT-S 106</td>
			<td></td>
		</tr>
		<tr>
			<td>Fine Scissors to cut fascia/connective tissue</td>
			<td>Fine Science Tools</td>
			<td>14058-09</td>
			<td></td>
		</tr>
		<tr>
			<td>Halsey needle holder</td>
			<td>Fine Science Tools</td>
			<td>12001-13</td>
			<td></td>
		</tr>
		<tr>
			<td>Kelly Hemostat for rats: muscle clamp to minimize bleeding when cut</td>
			<td>Fine Science Tools</td>
			<td>13018-14</td>
			<td></td>
		</tr>
		<tr>
			<td>Polyethelyne 50 tubing, catheter tubing 100 ft</td>
			<td>Braintree Scientific</td>
			<td>.023&#34; &#215; .038&#8221;</td>
			<td></td>
		</tr>
		<tr>
			<td>Schwartz microserrefine vascular clamps</td>
			<td>Fine Science Tools</td>
			<td>18052-01 (straight)</td>
			<td></td>
		</tr>
		<tr>
			<td></td>
			<td></td>
			<td>18052-03 (curved)</td>
			<td></td>
		</tr>
		<tr>
			<td>Surgical Scissors to cut skin</td>
			<td>Fine Science Tools</td>
			<td>14002-12</td>
			<td></td>
		</tr>
		<tr>
			<td>Vannas-Tubingen Spring scissors for arteriotomy</td>
			<td>Fine Science Tools</td>
			<td>15003-08</td>
			<td></td>
		</tr>
	</tbody>
</table>

preparation of decellularized kidney scaffolds in rats

Tissue engineering is a cutting-edge discipline in biomedicine. Cell culture techniques can be applied for regeneration of functional tissues and organs to replace diseased or damaged organs. Scaffolds are needed to facilitate the generation of three-dimensional organs or tissues using differentiated stem cells in vivo. In this report, we describe a novel method for developing vascularized scaffolds using decellularized rat kidneys. Eight-week-old Sprague-Dawley rats were used in this study, and heparin was injected into the heart to facilitate flow into the renal vessels, allowing heparin to perfuse into the renal vessels. The abdominal cavity was opened, and the left kidney was collected. The collected kidneys were perfused for 9 h using detergents, such as Triton X-100 and sodium dodecyl sulfate, to decellularize the tissue. Decellularized kidney scaffolds were then gently washed with 1% penicillin/streptomycin and heparin to remove cellular debris and chemical residues. Transplantation of stem cells with the decellularized vascular scaffolds is expected to facilitate the generation of new organs. Thus, the vascularized scaffolds may provide a foundation for tissue engineering of organ grafts in the future.

The gross morphology of rat kidneys was dark red (Figure 1A). After decellularization, the kidney became pale and translucent (Figure 1D). Residual genomic DNA was assessed with a commercial kit according to the manufacturer&#8217;s instructions, in decellularized kidney scaffolds and compared with that in native kidneys (control). Quantitative analysis confirmed that tissue genomic DNA was almost eliminated after decellularization. From 14 cases, the average DN...

Watch this Scientific Journal Video about Preparation of Decellularized Kidney Scaffolds in Rats at JoVE.com

Preparation of Decellularized Kidney Scaffolds in Rats

This protocol introduces a method to develop a scaffold using decellularized rat kidneys. The protocol includes decellularization and recellularization processes to confirm bioavailability. Decellularization is performed using Triton X-100 and sodium dodecyl sulfate.

Tissue engineering is a cutting-edge discipline in biomedicine. Cell culture techniques can be applied for regeneration of functional tissues and organs ...

This protocol makes it possible to develop vascularized scaffolds using kidneys in a rat model. The kidney is the most suitable organ for scaffolds of differentiated stem cells. This is a highly successful protocol for decellularization of the kidney.It effectively removes the nuclei with minimal destruction of the ECM ultrastructure. This technique can be applied to transplantation medicine and tissue engineering. Demonstrating the procedure will be Kim Joo Hyoung, an MD/PhD associate professor of plastic surgery from my laboratory.To begin, place the eight-week-old Sprague Dawley rat on a warming pad, and position a rectal thermometer probe in the rectum to monitor core temperature. After anesthetizing the rat, place it in a supine position, and secure the four limbs to the table with tape. Shave and clean the abdomen with germicidal soap.Apply 2%Betadine for at least one to two minutes, then wipe it off with a 70%ethanol solution. Repeat this sequence three times. Cover the operative field with a sterile, fenestrated drape.Make a vertical abdominal incision, and expose the left kidney, ureter, abdominal aorta, and inferior vena cava. Dissect the tissue just before cutting the pedicle. Prepare 50 milliliters of perfusion solution per rat by mixing PBS with approximately 10 units per milliliter heparin.Mix equal volumes of 8%PFA with PBS to make the 4%PFA solution. Extend the vertical abdominal incision cranially, making sure to draw the scissors away from the organs when cutting to avoid damage. Continue the incision through the rib cage, and then cut through the diaphragm by lifting the sternum.Retract the loose flap of skin out of the way with an Allis clamp, and free the heart by tearing any connective tissue with the forceps. Open the PBS line, and ensure that it is flowing before placing the needle into the left ventricle. Hold the heart gently with blunt forceps, and use a hemostat to control the needle.The needle should be inserted no more than a quarter inch. While supporting the heart with the needle and hemostat, locate the right atrium, and snip through it with iridectomy scissors. Rest the hemostat on the rat's body, and make sure the needle is still positioned inside the heart.Continue perfusing PBS for four minutes or longer if there is still blood visible in the kidney and liver. Harvest the left kidney with the abdominal aorta and inferior vena cava. Ligate the ureter, thoracic aorta, superior vena cava, and branches of the abdominal aorta.Keep the organ hydrated in DPBS in a 10-centimeter Petri dish. Cannulate the abdominal aorta and inferior vena cava with a 23-gauge catheter. To remove residual blood, connect the cannula with a peristaltic pump, and wash the organ with 500 milliliters of DPBS and 16 units per milliliter heparin for 90 minutes at five rpm and 37 degrees Celsius.To decellularize the kidney, perfuse it with 1%Triton X-100 for three hours and then with 0.75%SDS solution for six hours at a constant pressure of 40 milliliters of mercury. To remove residual SDS, perfuse the sample with 1%penicillin in distilled water for 18 hours and then with sterile DPBS and 16 units per milliliter heparin for 90 minutes. The gross morphology of rat kidneys was dark red.After decellularization, the kidney became pale and translucent. Residual genomic DNA was quantified in decellularized kidney scaffolds and compared with that in native kidneys, confirming that tissue genomic DNA was almost eliminated after decellularization. From 14 cases, the average DNA contents were 115.05 nanograms per microliter for the control and 1.96 nanograms per microliter for the decellularized scaffold.In total, 98.3%of DNA was removed. The three-dimensional structure was maintained, and acellular glomeruli were preserved in the cortical parenchyma. When inserting the needle into the left ventricle, it should be inserted no more than a quarter inch.Any further insertion may come out the other side. We have confidence that this technique will open a new prospect in the field of tissue engineering.

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Medicine

Acute Myocardial Infarction in Rats

With heart failure leading the cause of death in the USA (Hunt), biomedical research is fundamental to advance medical treatments for cardiovascular diseases. Animal models that mimic human cardiac disease, such as myocardial infarction (MI) and ischemia-reperfusion (IR) that induces heart failure as well as pressure-overload (transverse aortic constriction) that induces cardiac hypertrophy and heart failure (Goldman and Tarnavski), are useful models to study cardiovascular disease. In particular, myocardial ischemia (MI) is a leading cause for cardiovascular morbidity and mortality despite controlling certain risk factors such as arteriosclerosis and treatments via surgical intervention (Thygesen). Furthermore, an acute loss of the myocardium following myocardial ischemia (MI) results in increased loading conditions that induces ventricular remodeling of the infarcted border zone and the remote non-infarcted myocardium. Myocyte apoptosis, necrosis and the resultant increased hemodynamic load activate multiple biochemical intracellular signaling that initiates LV dilatation, hypertrophy, ventricular shape distortion, and collagen scar formation. This pathological remodeling and failure to normalize the increased wall stresses results in progressive dilatation, recruitment of the border zone myocardium into the scar, and eventually deterioration in myocardial contractile function (i.e. heart failure). The progression of LV dysfunction and heart failure in rats is similar to that observed in patients who sustain a large myocardial infarction, survive and subsequently develops heart failure (Goldman). The acute myocardial infarction (AMI) model in rats has been used to mimic human cardiovascular disease; specifically used to study cardiac signaling mechanisms associated with heart failure as well as to assess the contribution of therapeutic strategies for the treatment of heart failure. The method described in this report is the rat model of acute myocardial infarction (AMI). This model is also referred to as an acute ischemic cardiomyopathy or ischemia followed by reperfusion (IR); which is induced by an acute 30-minute period of ischemia by ligation of the left anterior descending artery (LAD) followed by reperfusion of the tissue by releasing the LAD ligation (Vasilyev and McConnell). This protocol will focus on assessment of the infarct size and the area-at-risk (AAR) by Evan's blue dye and triphenyl tetrazolium chloride (TTC) following 4-hours of reperfusion; additional comments toward the evaluation of cardiac function and remodeling by modifying the duration of reperfusion, is also presented. Overall, this AMI rat animal model is useful for studying the consequence of a myocardial infarction on cardiac pathophysiological and physiological function.

The rat model of acute myocardial infarction (AMI) is useful to study the consequence of a MI on cardiac pathophysiological and physiological function.

With heart failure leading the cause of death in the USA (Hunt), biomedical research is fundamental to advance medical treatments for cardiovascular ...

Orthotopic Liver Transplantation in Rats

Clinical progress in the field of liver transplantation has been largely supported by animal models1,2. Since the publication of the first orthotopic rat liver transplantation in 1979 by Kamada et al.3, this model has remained the gold standard despite various proposed alternative techniques4. Nevertheless, its broader use is limited by its steep learning curve5.
In this video paper, we show a simple and easy-to-establish revision of Kamada's two-cuff technique. The suprahepatic vena cava anastomosis is performed manually with a running suture, and the vena porta and infrahepatic vena cava anastomoses are performed utilizing a quick-linker cuff system6. Manufacturing the quick-linker kit is shown in a separate video paper.

We present an easy-to-establish revision of the classical two-cuff technique for orthotopic liver transplantation in rat.

Clinical progress in the field of liver transplantation has been largely supported by animal models1,2. Since the publication of the first orthotopic rat ...

Assessment of Vascular Function in Patients With Chronic Kidney Disease

Patients with chronic kidney disease (CKD) have significantly increased risk of cardiovascular disease (CVD) compared to the general population, and this is only partially explained by traditional CVD risk factors. Vascular dysfunction is an important non-traditional risk factor, characterized by vascular endothelial dysfunction (most commonly assessed as impaired endothelium-dependent dilation [EDD]) and stiffening of the large elastic arteries. While various techniques exist to assess EDD and large elastic artery stiffness, the most commonly used are brachial artery flow-mediated dilation (FMDBA) and aortic pulse-wave velocity (aPWV), respectively. Both of these noninvasive measures of vascular dysfunction are independent predictors of future cardiovascular events in patients with and without kidney disease. Patients with CKD demonstrate both impaired FMDBA, and increased aPWV. While the exact mechanisms by which vascular dysfunction develops in CKD are incompletely understood, increased oxidative stress and a subsequent reduction in nitric oxide (NO) bioavailability are important contributors. Cellular changes in oxidative stress can be assessed by collecting vascular endothelial cells from the antecubital vein and measuring protein expression of markers of oxidative stress using immunofluorescence. We provide here a discussion of these methods to measure FMDBA, aPWV, and vascular endothelial cell protein expression.

The degree of vascular dysfunction and contributing physiological mechanisms can be assessed in patients with chronic kidney disease by measuring brachial artery flow-mediated dilation, aortic pulse-wave velocity, and vascular endothelial cell protein expression.

Patients with chronic kidney disease (CKD) have significantly increased risk of cardiovascular disease (CVD) compared to the general population, and this ...

Mouse Kidney Transplantation: Models of Allograft Rejection

Rejection of the transplanted kidney in humans is still a major cause of morbidity and mortality. The mouse model of renal transplantation closely replicates both the technical and pathological processes that occur in human renal transplantation. Although mouse models of allogeneic rejection in organs other than the kidney exist, and are more technically feasible, there is evidence that different organs elicit disparate rejection modes and dynamics, for instance the time course of rejection in cardiac and renal allograft differs significantly in certain strain combinations. This model is an attractive tool for many reasons despite its technical challenges. As inbred mouse strain haplotypes are well characterized it is possible to choose donor and recipient combinations to model acute allograft rejection by transplanting across MHC class I and II loci. Conversely by transplanting between strains with similar haplotypes a chronic process can be elicited were the allograft kidney develops interstitial fibrosis and tubular atrophy. We have modified the surgical technique to reduce operating time and improve ease of surgery, however a learning curve still needs to be overcome in order to faithfully replicate the model. This study will provide key points in the surgical procedure and aid the process of establishing this technique.

Here, we present a protocol to study the immunology of rejection. The surgical model presented reports a short operating time and a concise technique. Depending on the donor-recipient strain combination, the transplanted kidney may develop acute cellular rejection or chronic allograft damage, defined by interstitial fibrosis and tubular atrophy.

Rejection of the transplanted kidney in humans is still a major cause of morbidity and mortality. The mouse model of renal transplantation closely ...

Murine Kidney Transplant Technique

The first mouse kidney transplant technique was published in 19731 by the Russell laboratory. Although it took some years for other labs to become proficient in and utilize this technique, it is now widely used by many laboratories around the world. A significant refinement to the original technique using the donor aorta to form the arterial anastomosis instead of the renal artery was developed and reported in 1993 by Kalina and Mottram 2 with a further advancement coming from the same laboratory in 1999 3. While one can become proficient in this model, a search of the literature reveals that many labs still experience a high proportion of graft loss due to arterial thrombosis. We describe here a technique that was devised in our laboratory that vastly reduces the arterial thrombus reported by others 4,5. This is achieved by forming a heel-and-toe cuff of the donor infra-renal aorta that facilitates a larger anastomosis and straighter blood flow into the kidney.

The goal of this manuscript is to describe the steps required to perform a kidney transplant in a mouse, paying particular attention to the details of the arterial anastomosis.

The first mouse kidney transplant technique was published in 19731 by the Russell laboratory. Although it took some years for other labs to become ...

Normothermic Ex Vivo Kidney Perfusion for the Preservation of Kidney Grafts prior to Transplantation

Kidney transplantation has become a well-established treatment option for patients with end-stage renal failure. The persisting organ shortage remains a serious problem. Therefore, the acceptance criteria for organ donors have been extended leading to the usage of marginal kidney grafts. These marginal organs tolerate cold storage poorly resulting in increased preservation injury and higher rates of delayed graft function. To overcome the limitations of cold storage, extensive research is focused on alternative normothermic preservation methods.
Ex vivo normothermic organ perfusion is an innovative preservation technique. The first experimental and clinical trials for ex vivo lung, liver, and kidney perfusions demonstrated favorable outcomes.
In addition to the reduction of cold ischemic injury, the method of normothermic kidney storage offers the opportunity for organ assessment and repair. This manuscript provides information about kidney retrieval, organ preservation techniques, and isolated ex vivo normothermic kidney perfusion (NEVKP) in a porcine model. Surgical techniques, set up for the perfusion solution and the circuit, potential assessment options, and representative results are demonstrated.

Normothermic Ex Vivo Kidney Perfusion for the Preservation of Kidney Grafts prior to Transplantation

The severe organ shortage has resulted in increased use of marginal kidney grafts for transplantation. This has triggered interest in alternative storage methods, since marginal grafts especially tolerate cold storage poorly. The technique of normothermic ex vivo kidney perfusion (NEVKP) represents a novel preservation method for kidney grafts prior to &#160;transplantation.

Kidney transplantation has become a well-established treatment option for patients with end-stage renal failure. The persisting organ shortage remains a ...

Intravascular Delivery of Biologics to the Rat Kidney

The renal microvascular compartment plays an important role in the progression of kidney disease and hypertension, leading to the development of End Stage Renal Disease with high risk of death for cardiovascular events. Moreover, recent clinical studies have shown that renovascular structure and function may have a great impact on functional renal recovery after surgery. Here, we describe a protocol for the delivery of drugs into the renal artery of rats. This procedure offers significant advantages over the frequently used systemic administration as it may allow a more localized therapeutic effect. In addition, the use of rodents in pharmacodynamic analysis of preclinical studies may be cost effective, paving the way for the design of translational experiments in larger animal models. Using this technique, infusion of rat recombinant Vascular Endothelial Growth Factor (VEGF) protein in rats has induced activation of VEGF signaling as shown by increased expression of FLK1, pAKT/AKT, pERK/ERK. In summary, we established a protocol for the intrarenal delivery of drugs in rats, which is simple and highly reproducible.

The administration of drugs for recovery of kidney function requires control of the localization and distribution of the therapeutic compound. Here, we describe in detail a simple technique for intrarenal delivery of drugs in rats. This procedure may be easily performed with no mortality and high reproducibility.

The renal microvascular compartment plays an important role in the progression of kidney disease and hypertension, leading to the development of End Stage ...

Assessment of Kidney Function in Mouse Models of Glomerular Disease

The use of murine models to mimic human kidney disease is becoming increasingly common. Our research is focused on the assessment of glomerular function in diabetic nephropathy and podocyte-specific VEGF-A knock-out mice; therefore, this protocol describes the full kidney work-up used in our lab to assess these mouse models of glomerular disease, enabling a vast amount of information regarding kidney and glomerular function to be obtained from a single mouse. In comparison to alternative methods presented in the literature to assess glomerular function, the use of the method outlined in this paper enables the glomerular phenotype to be fully evaluated from multiple aspects. By using this method, the researcher can determine the kidney phenotype of the model and assess the mechanism as to why the phenotype develops. This vital information on the mechanism of disease is required when examining potential therapeutic avenues in these models. The methods allow for detailed functional assessment of the glomerular filtration barrier through measurement of the urinary albumin creatinine ratio and individual glomerular water permeability, as well as both structural and ultra-structural examination using the Periodic Acid Schiff stain and electron microscopy. Furthermore, analysis of the genes dysregulated at the mRNA and protein level enables mechanistic analysis of glomerular function. This protocol outlines the generic but adaptable methods that can be applied to all mouse models of glomerular disease.

This protocol describes a full kidney work-up that should be carried out in mouse models of glomerular disease. The methods allow for detailed functional, structural, and mechanistic analysis of glomerular function, which can be applied to all mouse models of glomerular disease.

The use of murine models to mimic human kidney disease is becoming increasingly common. Our research is focused on the assessment of glomerular function ...

Platelet-based Detection of Nitric Oxide in Blood by Measuring VASP Phosphorylation

Platelets are the blood components responsible for proper blood clotting. Their function is highly regulated by various pathways. One of the most potent vasoactive agents, nitric oxide (NO), can also act as a powerful inhibitor of platelet aggregation. Direct NO detection in blood is very challenging due to its high reactivity with cell-free hemoglobin that limits NO half-life to the millisecond range. Currently, NO changes after interventions are only estimated based on measured changes of nitrite and nitrate (members of the nitrate-nitrite-NO metabolic pathway). However precise, these measurements are rather difficult to interpret vis a vis actual NO changes, due to the naturally high baseline nitrite and nitrate levels that are several orders of magnitude higher than expected changes of NO itself. Therefore, the development of direct and simple methods that would allow one to detect NO directly is long overdue. This protocol addresses a potential use of platelets as a highly sensitive NO sensor in blood. It describes initial platelet rich plasma (PRP) and washed platelet preparations and the use of nitrite and deoxygenated red blood cells as NO generators. Phosphorylation of VASP at serine 239 (P-VASPSer239) is used to detect the presence of NO. The fact that VASP protein is highly expressed in platelets and that it is rapidly phosphorylated when NO is present leads to a unique opportunity to use this pathway to directly detect NO presence in blood.

Here, we present a protocol to address the potential use of platelets as a highly sensitive nitric oxide sensor in blood. It describes initial platelet preparation and the use of nitrite and deoxygenated red blood cells as nitric oxide generators.

Platelets are the blood components responsible for proper blood clotting. Their function is highly regulated by various pathways. One of the most potent ...

Optical Clearing and Imaging of Immunolabeled Kidney Tissue

Optical clearing techniques render tissue transparent by equilibrating the refractive index throughout a sample for subsequent three-dimensional (3-D) imaging. They have received great attention in all research areas for the potential to analyze microscopic multicellular structures that extend over macroscopic distances. Given that kidney tubules, vasculature, nerves, and glomeruli extend in many directions, which have been only partially captured by traditional two-dimensional techniques so far, tissue clearing also opened up many new areas of kidney research. The list of optical clearing methods is rapidly growing, but it remains difficult for beginners in this field to choose the best method for a given research question. Provided here is a simple method that combines antibody labeling of thick mouse kidney slices; optical clearing with cheap, non-toxic and ready-to-use chemical ethyl cinnamate; and confocal imaging. This protocol describes how to perfuse kidneys and use an antigen-retrieval step to increase antibody- binding without requiring specialized equipment. Its application is presented in imaging different multicellular structures within the kidney, and how to troubleshoot poor antibody penetration into tissue is addressed. We also discuss the potential difficulties of imaging endogenous fluorophores and acquiring very large samples and how to overcome them. This simple protocol provides an easy-to-setup and comprehensive tool to study tissue in three dimensions.

The combination of antibody labeling, optical clearing, and advanced light microscopy allows three-dimensional analysis of complete structures or organs. Described here is a simple method to combine immunolabeling of thick kidney slices, optical clearing with ethyl cinnamate, and confocal imaging that enables visualization and quantification of three-dimensional kidney structures.

Optical clearing techniques render tissue transparent by equilibrating the refractive index throughout a sample for subsequent three-dimensional (3-D) ...