Porcine Kidney Research Articles

IL-1 receptor antagonist anakinra downregulates inflammatory cytokines during renal normothermic machine perfusion: Preliminary results.

The interleukin 1 (IL-1) cytokine group plays a key role in sterile inflammation and may be an important target for transplant-related renal injury. This study examined the effects of anakinra, a non-specific IL-1 receptor antagonist, administered during normothermic machine perfusion (NMP) of porcine kidneys. Paired porcine kidneys (n = 5 pairs) underwent 15 min of warm ischemia plus 2 h of static cold storage in ice. Kidneys were then perfused with autologous whole blood using an exvivo NMP platform. Kidneys were randomly allocated to receive anakinra or vehicle administered at the start of NMP. Cortical biopsies were collected at baseline before ischemic injury and at the end of NMP. Functional parameters were recorded and calculated, and inflammatory markers were measured by qPCR and ELISA techniques. During NMP, there were no statistically significant differences in renal blood flow, urine output, creatinine clearance or fractional excretion of sodium in the anakinra and control groups. The administration of anakinra significantly downregulated transcriptional expression of IL-6, Fas ligand and intercellular adhesion molecule 1 (p = 0.029, 0.029, 0.028, respectively). Anakinra, an IL-1 receptor blocker, successfully attenuated the downstream inflammatory and immune-mediated response within the kidney during NMP.

Normothermic Machine Perfusion Reconstitutes Porcine Kidney Tissue Metabolism But Induces an Inflammatory Response, Which Is Reduced by Complement C5 Inhibition.

Normothermic machine perfusion (NMP) is a clinical strategy to reduce renal ischemia-reperfusion injury (IRI). Optimal NMP should restore metabolism and minimize IRI induced inflammatory responses. Microdialysis was used to evaluate renal metabolism. This study aimed to assess the effect of complement inhibition on NMP induced inflammatory responses. Twenty-two pig kidneys underwent 18h of static cold storage (SCS) followed by 4h of NMP using a closed-circuit system. Kidneys were randomized to receive a C5-inhibitor or placebo during SCS and NMP. Perfusion resulted in rapidly stabilized renal flow, low renal resistance, and urine production. During SCS, tissue microdialysate levels of glucose and pyruvate decreased significantly, whereas glycerol increased (p < 0.001). In the first hour of NMP, glucose and pyruvate increased while glycerol decreased (p < 0.001). After 4h, all metabolites had returned to baseline. Inflammatory markers C3a, soluble C5b-9, TNF, IL-6, IL-1β, IL-8, and IL-10 increased significantly during NMP in perfusate and kidney tissue. C5-inhibition significantly decreased perfusate and urine soluble C5b-9 (p < 0.001; p = 0.002, respectively), and tissue IL-1β (p = 0.049), but did not alter other inflammatory markers. Microdialysis can accurately monitor the effect of NMP on renal metabolism. Closed-circuit NMP induces inflammation, which appeared partly complement-mediated. Targeting additional immune inhibitors should be the next step.

Optimized protocol for the multiomics processing of cryopreserved human kidney tissue.

Biobanking of tissue from clinically obtained kidney biopsies for later analysis with multiomic approaches, such as single-cell technologies, proteomics, metabolomics, and the different types of imaging, is an inevitable step to overcome the need of disease model systems and toward translational medicine. Hence, collection protocols that ensure integration into daily clinical routines by the usage of preservation media that do not require liquid nitrogen but instantly preserve kidney tissue for both clinical and scientific analyses are necessary. Thus, we modified a robust single-nucleus dissociation protocol for kidney tissue stored snap-frozen or in the preservation media RNAlater and CellCover. Using at first porcine kidney tissue as a surrogate for human kidney tissue, we conducted single-nucleus RNA sequencing with the widely recognized Chromium 10X Genomics platform. The resulting datasets from each storage condition were analyzed to identify any potential variations in transcriptomic profiles. Furthermore, we assessed the suitability of the preservation media for additional analysis techniques such as proteomics, metabolomics, and the preservation of tissue architecture for histopathological examination including immunofluorescence staining. In this study, we show that in daily clinical routines, the preservation medium RNAlater facilitates the collection of highly preserved human kidney biopsies and enables further analysis with cutting-edge techniques like single-nucleus RNA sequencing, proteomics, and histopathological evaluation. Only metabolome analysis is currently restricted to snap-frozen tissue. This work will contribute to build tissue biobanks with well-defined cohorts of the respective kidney disease that can be deeply molecularly characterized, opening up new horizons for the identification of unique cells, pathways and biomarkers for the prevention, early identification, and targeted therapy of kidney diseases.NEW & NOTEWORTHY In this study, we addressed challenges in integrating clinically obtained kidney biopsies into everyday clinical routines. Using porcine kidneys, we evaluated preservation media (RNAlater and CellCover) versus snap freezing for multi-omics processing. Our analyses highlighted RNAlater's suitability for single-nucleus RNA sequencing, proteome analysis and histopathological evaluation. Only metabolomics are currently restricted to snap-frozen biopsies. Our research established a cryopreservation protocol that facilitates tissue biobanking for advancing precision medicine in nephrology.

Comparison of holmium:yttrium-aluminium-garnet (YAG), thulium fiber laser, and pulsed thulium:YAG lasers on soft tissue: an ex vivo study.

To assess laser-tissue interactions through ablation, coagulation, and carbonisation characteristics in a non-perfused porcine kidney model between three pulsed lasers: holmium (Ho): yttrium-aluminium-garnet (YAG), thulium fiber laser (TFL), and pulsed thulium (p-Tm):YAG. A 150-W Ho:YAG, a 60-W TFL, and a 100-W p-Tm:YAG lasers were compared. The laser settings that can be set identically between the three lasers and be clinically relevant for prostate laser enucleation were identified and used on fresh, unfrozen porcine kidneys. Laser incisions were performed using stripped laser fibers of 365 and 550 μm, set at distances of 0 and 1 mm from the tissue surface at a constant speed of 2 mm/s. Histological analysis evaluated shape, depth, width of the incision, axial coagulation depth, and presence of carbonisation. Incision depths, widths, and coagulation zones were greater with Ho:YAG and p-Tm:YAG lasers than TFL. Although no carbonisation was found with the Ho:YAG and p-Tm:YAG lasers, it was common with TFL, especially at high frequencies. The shapes of the incisions and coagulation zones were more regular and homogeneous with the p-Tm:YAG laser and TFL than with Ho:YAG laser. Regardless of the laser used, short pulse durations resulted in deeper incisions than long pulse durations. Concerning the distance, we found that to be effective, TFL had to be used in contact with the tissue. Finally, 365-μm fibers resulted in deeper incisions, while 550-μm fibers led to wider incisions and larger coagulation zones. Histological analysis revealed greater tissue penetration with the p-Tm:YAG laser compared to the TFL, while remaining less than with Ho:YAG. Its coagulation properties seem interesting insofar as it provides homogeneous coagulation without carbonisation, while incisions remained uniform without tissue laceration. Thus, the p-Tm:YAG laser appears to be an effective alternative to Ho:YAG and TFL lasers in prostate surgery.

Impact of technological factors on diamine oxidase (DAO) activity in porcine kidney extracts as active ingredient for the dietary management of histamine intolerance

Histamine intolerance is associated with impaired histamine metabolism due to diamine-oxidase (DAO) enzyme deficiency at intestinal level. The recommended strategy to alleviate the symptomatology is a low-histamine diet supplemented with DAO. Different sources of DAO enzyme have been characterized in the literature (animal, vegetal and microbial), although only the porcine kidney protein extract has been approved as food supplement. Despite optimistic clinical results of DAO supplementation, variability in enzymatic activity of this type of active ingredient is reported, potentially linked to manufacturing processes. The aim of this work was to evaluate the impact of the raw material and the technological process of obtaining the porcine kidney protein extract on DAO activity, and its evolution during storage at room temperature (25 °C) and refrigeration (4 °C). Twenty batches of DAO-containing extract were analyzed and found to have a consistent histamine-degrading activity. The powder extract was prepared by mincing and homogenizing porcine kidneys, defatting with acetone, and drying at 40 °C for 6 h. The inclusion of a biocidal step before acetone extraction was evaluated on DAO activity. The use of sodium hypochlorite and irradiation (8kGy) did not have a negative impact on DAO activity. Moreover, the inclusion of an initial freeze-drying step of the raw material yielded an extract with higher DAO activity. On the other hand, the effect of applying higher temperatures (70 °C, 80 °C, and 90 °C) during the extract drying process for 3 and 6 h was evaluated, reporting a significant decrease of the enzymatic activity, with losses of 10–20 % for every 10 °C increase in temperature. Refrigeration was the only storage method capable of preserving enzymatic activity for at least 24 months. The manufacturing and storage of porcine kidney extract are crucial steps in the formulation of DAO supplements suitable for the treatment of histamine intolerance.

An in vitro study of irrigation rate, operator duty cycle and intrarenal temperature in superpulse fiber thulium laser lithotripsy

ObjectiveThe present study aimed to examine the relationship between irrigation velocity, operator duty cycle (ODC), and intrarenal temperature during retrograde intrarenal surgery with a superpulse fiber thulium laser.MethodsPlace the stones into the fresh isolated porcine kidneys, use puncture needle to place the temperature probe 2 mm around the stones, and place the pressure probes in the upper calyx, lower calyx, and renal pelvis. Place the entire setup in a 37 °C constant temperature water bath to simulate the human body environment. The laser power varies between 10 and 30 W, and the irrigation speed is 10-30 ml/min. Additionally, at a laser power of 20 W and an irrigation speed of 10 ml/min, different On-Duty Cycles (ODC) are set. Monitor the changes in temperature and pressure.ResultsA direct proportionality of temperature in the kidney to the rate of irrigation has been reported between 10 W and 30 W laser powers. The percentage ratio of the rate of irrigation and power in the laser is 1:1, which can keep the temperature in the kidney at a safe level. At a laser power of 20 W and irrigation of 10 ml/min, the temperature inside the kidney increases sharply with the increase in ODC. By decreasing the ratio of ODC, the increase of temperature inside the kidney can be brought to a great reduction.ConclusionMaintaining a 1:1 ratio between laser power and irrigation speed can effectively prevent thermal damage or injury to kidney tissue.Additionally, by adjusting the On-Duty Cycle (ODC) ratio, the intrarenal temperature can also be reduced.

Plasma exchange and intravenous immunoglobulin prolonged the survival of a porcine kidney xenograft in a sensitized, deceased human recipient.

The primary limitation to kidney transplantation is organ shortage. Recent progress in gene editing and immunosuppressive regimens has made xenotransplantation with porcine organs a possibility. However, evidence in pig-to-human xenotransplantation remains scarce, and antibody-mediated rejection (AMR) is a major obstacle to clinical applications of xenotransplantation. We conducted a kidney xenotransplantation in a deceased human recipient using a porcine kidney with five gene edits (5GE) on March 25th, 2024 at Xijing Hospital, China. Clinical-grade immunosuppressive regimens were employed, and the observation period lasted 22days. We collected and analyzed the xenograft function, ultrasound findings, sequential protocol biopsies, and immune surveillance of the recipient during the observation. The combination of 5GE in the porcine kidney and clinical-grade immunosuppressive regimens prevented hyperacute rejection. The xenograft kidney underwent delayed graft function in the first week, but urine output increased later and the single xenograft kidney maintained electrolyte and pH homeostasis from postoperative day (POD) 12 to 19. We observed AMR at 24h post-transplantation, due to the presence of pre-existing anti-porcine antibodies and cytotoxicity before transplantation; this AMR persisted throughout the observation period. Plasma exchange and intravenous immunoglobulin treatment mitigated the AMR. We observed activation of latent porcine cytomegalovirus toward the end of the study, which might have contributed to coagulation disorder in the recipient. 5GE and clinical-grade immunosuppressive regimens were sufficient to prevent hyperacute rejection during pig-to-human kidney xenotransplantation. Pre-existing anti-porcine antibodies predisposed the xenograft to AMR. Plasma exchange and intravenous immunoglobulin were safe and effective in the treatment of AMR after kidney xenotransplantation.

Assessment of Intrarenal Pressure through Dilatation State of the Renal Collecting System

Introduction: The aim of the study was to explore the relationship between the dilation states of the renal collecting system in flexible ureteroscopy (f-URS) view and intrarenal pressure (IRP). Methods: Fifteen porcine kidneys were randomly selected and numbered 1 through 15. Pressure transducers were inserted into the renal calyx via puncture and adjusted to a zero position. The distal end of the f-URS probe was placed within the renal pelvis. Perfusion rates of 50 mL/min, 80 mL/min, and 100 mL/min were utilized. We observed the relationship between the dilation state of the renal collecting system and changes in IRP. The state of complete dilation was defined as an unchanging spatial morphology of the renal collecting system as visualized during f-URS. Results: With irrigation rates of 50 mL/min, 80 mL/min, and 100 mL/min, IRP values at the moment of complete dilation of the renal collecting system ranged from 16 to 18 cm H2O, 16–19 cm H2O, and 16–19 cm H2O, respectively. Maximum IRPs ranged from 47 to 49 cm H2O, 82–85 cm H2O, and 97–100 cm H2O, respectively. Prior to complete dilation of the renal collecting system, IRP consistently remained below 20 cm H2O. However, following full dilation of the renal collecting system, IRP rose rapidly and rapidly surpassed 20 cm H2O. Despite sustained elevations in IRP following full dilation, no significant alterations in the renal collecting system dilated morphological were observed with f-URS. Conclusions: In vitro experiments indicate that when the renal collecting system is not fully dilated, the IRP is consistently less than 20 cm H2O. Evaluation of IRP being within a safe range can be determined by assessing the dilation status of the renal collecting system.

Palmitoylation regulates norepinephrine transporter uptake, surface localization, and total expression with pathogenic implications in postural orthostatic tachycardia syndrome.

Postural orthostatic tachycardia syndrome (POTS) is an adrenergic signaling disorder characterized by excessive plasma norepinephrine, postural tachycardia, and syncope. The norepinephrine transporter (NET) modulates adrenergic homeostasis via the reuptake of extracellular catecholamines and is implicated in the pathogenesis of adrenergic and neurological disorders. In this study, we reveal NET is palmitoylated in male Sprague-Dawley rats and Lilly Laboratory Cell Porcine Kidney (LLC-PK1) cells. S-palmitoylation, or the addition of a 16-carbon saturated fatty acid, is a reversible post-translational modification responsible for the regulation of numerous biological mechanisms. We found that LLC-PK1 NET is dynamically palmitoylated, and that inhibition with the palmitoyl acyltransferase (DHHC) inhibitor, 2-bromopalmitate (2BP) results in decreased NET palmitoylation within 90 min of treatment. This result was followed closely by a reduction in transport capacity, cell surface, and total cellular NET expression after 120 min of treatment. Increasing 2BP concentrations and treatment time revealed a nearly complete loss of total NET protein. Co-expression with individual DHHCs revealed a single DHHC enzyme, DHHC1, promoted wild-type (WT) hNET palmitoylation and elevated NET protein levels. The POTS-associated NET mutant, A457P, exhibits dramatically decreased transport capacity and cell surface levels which we have confirmed in the current study. In an attempt to recover A457P NET expression, we co-expressed the A457P variant with DHHC1 to drive expression as seen with the WT protein but instead saw an increase in NET N-terminal immuno-detectable forms and fragments. Elimination of a potential palmitoylation site at cysteine 44 in the N-terminal tail of hNET resulted in a low expression phenotype mimicking the A457P hNET variant. Further investigation of A457P NET palmitoylation and surface expression is necessary, but our preliminary novel findings reveal palmitoylation as a mechanism of NET regulation and suggest that dysregulation of this process may contribute to the pathogenesis of adrenergic disorders like POTS.

Magnetic Kidney Stone Removal

Abstract Residual fragments can remain after kidney stone extraction which may necessitate another intervention. A new approach needs to be developedis needed to lower the risk of disease severe side effects caused by these fragments. Magnetic nanoparticles can be applied due to their properties of being able to bind to residual fragments and to be extracted by an external magnetic field. Fractals and magnetic nanoparticles have been synthesized and characterized thoroughly. The small nanoparticles bind covalently to the kidney stones and a magnetic extraction of calcium oxalate fractals with magnetic nanoparticles is possible. The aggregation of nanoscale iron oxide nanoparticles can be induced with the addition of salt which improves the extraction process. The separation is validated by simulation and experimentally in a porcine kidney as well as in artificial kidney models. This proof-of-concept study successfullyis the fundament for a new waydemonstrated of extracting kidney stones extraction and including their fractals and might pave the way for new procedures in urology.

The Influence of Preablation Embolization Particle Size on the Size of the Microwave Ablation Zone in a Porcine Orthotopic Renal Tumor Model

PurposeTo combine arterial embolization with different embolic agents, followed by microwave ablation (MWA) in a porcine renal tumor (RT), to evaluate the ideal setting to produce the largest change in the size of the ablation zones (AZs). Materials and MethodsIn a transgenic porcine kidney, 32 sites were inoculation with 28 orthotopic RT produced. Experimental groups (23 tumors) underwent angiography with intra-arterial embolization using various embolic materials (calibrated particles from 40 to 1,200 μm and ethiodized oil) to achieve vascular stasis of the RT. MWA using a standard protocol (3 minutes at 65 W) was subsequently performed for all tumors. Next, a gross and histologic ex vivo analysis of the AZ was performed. ResultsControl group AZ volume without prior embolization was 5.24 cm3 (SD ± 0.55). AZs after embolization with 40 μm, 100 μm, 300–500 μm, 900–1,200 μm particles were significantly larger than those with MWA alone (mean, 15.39 cm3 [SD ± 4.54]; P = .002; 11.07 cm3 [SD ± 1.39]; P = .001; 8.68 cm3 [SD ± 0.77]; P = .001; and 9.90 cm3 [SD ± 1.62]; P = .002, respectively). Liquid embolic ethiodized oil emulsion did not create a significant increase in the AZ (5.92 cm3 [SD ± 1.43 cm3]; P = .492). ConclusionsPre-MWA arterial embolization in a porcine RT model produced a statistically significant increase in the AZ when compared with MWA alone. Using smaller particle size embolic material with distal embolization at the tumor arterioles (50–150 μm) produced the largest, almost 3-fold increase in AZ volume.

Making gene editing accessible in resource limited environments: recommendations to guide a first-time user.

The designer nuclease, CRISPR-Cas9 system has advanced the field of genome engineering owing to its programmability and ease of use. The application of these molecular scissors for genome engineering earned the developing researchers the Nobel prize in Chemistry in the year 2020. At present, the potential of this technology to improve global challenges continues to grow exponentially. CRISPR-Cas9 shows promise in the recent advances made in the Global North such as the FDA-approved gene therapy for the treatment of sickle cell anaemia and β-thalassemia and the gene editing of porcine kidney for xenotransplantation into humans affected by end-stage kidney failure. Limited resources, low government investment with an allocation of 1% of gross domestic production to research and development including a shortage of skilled professionals and lack of knowledge may preclude the use of this revolutionary technology in the Global South where the countries involved have reduced science and technology budgets. Focusing on the practical application of genome engineering, successful genetic manipulation is not easily accomplishable and is influenced by the chromatin landscape of the target locus, guide RNA selection, the experimental design including the profiling of the gene edited cells, which impacts the overall outcome achieved. Our assessment primarily delves into economical approaches of performing efficient genome engineering to support the first-time user restricted by limited resources with the aim of democratizing the use of the technology across low- and middle-income countries. Here we provide a comprehensive overview on existing experimental techniques, the significance for target locus analysis and current pitfalls such as the underrepresentation of global genetic diversity. Several perspectives of genome engineering approaches are outlined, which can be adopted in a resource limited setting to enable a higher success rate of genome editing-based innovations in low- and middle-income countries.

Assessing Biomarkers of Porcine Kidneys under Normothermic Machine Perfusion-Can We Gain Insight into a Marginal Organ?

To identify potentially transplantable organs in a pool of marginal kidneys, 33 porcine slaughterhouse kidneys were perfused for 4 h with whole blood. During the normothermic perfusion, plasma, urine, and tissue samples were taken. Several biomarkers for tubule injury, endothelial activation, and inflammatory response were evaluated for a potential correlation with macroscopic appearance, histology, and filtration activity. Generally, biomarker levels increased during perfusion. TLR-4, EDN-1, and NGAL were not associated with any classification. In contrast, a steeper increase in NAG and IL-6 in plasma correlated with a poor macroscopic appearance at 4 h, indicating a higher inflammatory response in the kidneys with worse macroscopy early on, potentially due to more damage at the tubules. Although long-term effects on the graft could not be assessed in this setting, early observation under machine perfusion with whole blood was feasible. It allowed the assessment of kidneys under conditions comparable to reperfusion. This setting could give surgeons further insight into the quality of marginal kidneys and an opportunity to pre-treat them.

Advancing Boiling Histotripsy Dose in Ex Vivo And In Vivo Renal Tissues Via Quantitative Histological Analysis and Shear Wave Elastography

ObjectiveIn the context of developing boiling histotripsy (BH) as a potential clinical approach for non-invasive mechanical ablation of kidney tumors, the concept of BH dose (BHD) was quantitatively investigated in porcine and canine kidney models in vivo and ex vivo. MethodsVolumetric lesions were produced in renal tissue using a 1.5-MHz 256-element HIFU-array with various pulsing protocols: pulse duration tp = 1–10 ms, number of pulses per point ppp = 1–15. Two BHD metrics were evaluated: BHD1 = ppp, BHD2 = tp × ppp. Quantitative assessment of lesion completeness was performed by their histological analysis and assignment of damage score to different renal compartments (i.e., cortex, medulla, and sinus). Shear wave elastography (SWE) was used to measure the Young's modulus of renal compartments in vivo vs ex vivo, and before vs after BH treatments. ResultsIn vivo tissue required lower BH doses to achieve identical degree of fractionation as compared to ex vivo. Renal cortex (homogeneous, low in collagen) was equal or higher in stiffness than medulla (anisotropic, collagenous), 5.8–12.2 kPa vs 4.7–9.6 kPa, but required lower BH doses to be fully fractionated. Renal sinus (fatty, irregular, with abundant collagenous structures) was significantly softer ex vivo vs in vivo, 4.9–5.1 kPa vs 9.7–15.2 kPa, but was barely damaged in either case with any tested BH protocols. BHD1 was shown to be relevant for planning the treatment of renal cortex (sufficient BHD1 = 5 pulses in vivo and 10 pulses ex vivo), while none of the tested doses resulted in complete fractionation of medulla or sinus. Post-treatment SWE imaging revealed reduction of tissue stiffness ex vivo by 27–58%, increasing with the applied dose, and complete absence of shear waves within in vivo lesions, both indicative of tissue liquefaction. ConclusionThe results imply that tissue resistance to mechanical fractionation, and hence required BH dose, are not solely determined by tissue stiffness but also depend on its composition and structural arrangement, as well as presence of perfusion. The SWE-derived reduction of tissue stiffness with increasing BH doses correlated with tissue damage score, indicating potential of SWE for post-treatment confirmation of BH lesion completeness.

Normothermic ex vivo kidney perfusion preserves mitochondrial and graft function after warm ischemia and is further enhanced by AP39

We previously reported that normothermic ex vivo kidney perfusion (NEVKP) is superior in terms of organ protection compared to static cold storage (SCS), which is still the standard method of organ preservation, but the mechanisms are incompletely understood. We used a large animal kidney autotransplant model to evaluate mitochondrial function during organ preservation and after kidney transplantation, utilizing live cells extracted from fresh kidney tissue. Male porcine kidneys stored under normothermic perfusion showed preserved mitochondrial function and higher ATP levels compared to kidneys stored at 4 °C (SCS). Mitochondrial respiration and ATP levels were further enhanced when AP39, a mitochondria-targeted hydrogen sulfide donor, was administered during warm perfusion. Correspondingly, the combination of NEVKP and AP39 was associated with decreased oxidative stress and inflammation, and with improved graft function after transplantation. In conclusion, our findings suggest that the organ-protective effects of normothermic perfusion are mediated by maintenance of mitochondrial function and enhanced by AP39 administration. Activation of mitochondrial function through the combination of AP39 and normothermic perfusion could represent a new therapeutic strategy for long-term renal preservation.

Genetically Modified Porcine Kidneys Have Sufficient Tissue Integrity for Use in Pig-to-Human Xenotransplantation.

We sought to determine if genetically modified porcine kidneys used for xenotransplantation had sufficient tissue integrity to support long-term function in a human recipient. Kidney transplantation remains the best available treatment for patients with end-stage kidney disease. However, a shortage of available donor human kidneys prevents many patients from achieving the benefits of transplantation. Xenotransplantation is a potential solution to this shortage. Recent pre-clinical human studies have demonstrated kidneys from genetically modified pig donors can be transplanted without hyperacute rejection and are capable of providing creatinine and other solute clearance. It is unknown whether the porcine kidneys would tolerate the relatively higher resting blood pressure in an adult human recipient compared with the pig donor or non-human primate (NHP) recipients used in translational studies. Furthermore, previous experience in NHPs raised concerns about the tissue integrity of the porcine ureter and post-xenotransplant growth of the porcine kidney. Kidneys recovered from porcine donors with 10 gene edits were transplanted into decedent brain-dead recipients who were not eligible for organ donation. Decedents underwent bilateral native nephrectomy before transplant and were followed for 3 to 7 days. Standard induction and maintenance immunosuppression was used as previously reported. Vital signs, including blood pressure, were recorded frequently. Kidney xenografts were assessed daily, serially biopsied, and were measured at implantation and study completion. Three decedents underwent successful xenotransplantation. Subcapsular hematomas developed, requiring incision of the xenograft capsules to prevent Page kidney. Blood pressures were maintained in a physiologic range for adult humans (median arterial pressures (MAP) 108.5mmHg (Interquartile Range (IQR): 97-114mmHg), 74mmHg (IQR: 71-78mmHg), and 95mmHg (IQR: 88-99mmHg, respectively) and no bleeding complications or aneurysm formation was observed. Serial biopsies were taken from the xenografts without apparent loss of tissue integrity despite the lack of a capsule. Ureteroneocystotomies remained intact without evidence of urine leak. Xenograft growth was observed, but plateaued, in 1 decedent with increased volume of the left and right xenografts by 25% and 26%, respectively, and in the context of human growth hormone levels consistently less <0.1ng/ml and insulin-like growth factor 1 levels ranging from 34-50ng/ml. The findings of this study suggest kidneys from 10-gene edited porcine donors have sufficient tissue integrity to tolerate xenotransplantation into a living human recipient. There was no evidence of anastomotic complications, and the xenografts tolerated needle biopsy without issue. Xenograft growth occurred but plateaued by the study end; further observation and investigation will be required to confirm this finding and elucidate underlying mechanisms.

261.10: Prolonged static cold storage results in significant pelvic hematomas during normothermic machine perfusion of porcine kidney grafts.

261.10: Prolonged static cold storage results in significant pelvic hematomas during normothermic machine perfusion of porcine kidney grafts.

327.6: Reduced inflammation and lymphocyte infiltration after reperfusion in triple knock-out porcine kidney xenografts expressing human transgenes transplanted to nonhuman primates.

327.6: Reduced inflammation and lymphocyte infiltration after reperfusion in triple knock-out porcine kidney xenografts expressing human transgenes transplanted to nonhuman primates.

P.037: A strategy for life-supporting porcine kidney xenograft in cynomolgus monkey: A comparison of two immunosuppressive drug treatment.

P.037: A strategy for life-supporting porcine kidney xenograft in cynomolgus monkey: A comparison of two immunosuppressive drug treatment.

447.2: Consistent long-term survival in consecutive cases of life-supporting porcine kidney xenotransplantation using 10GE source pigs.

447.2: Consistent long-term survival in consecutive cases of life-supporting porcine kidney xenotransplantation using 10GE source pigs.