Dynamic changes in the mouse hepatic lipidome following warm ischemia reperfusion injury.

Liver failure secondary to metabolic dysfunction-associated steatotic liver disease (MASLD) has become the most common cause for liver transplantation in many parts of the world. Moreover, the prevalence of MASLD not only increases the demand for liver transplantation, but also limits the supply of suitable donor organs because steatosis predisposes grafts to ischemia-reperfusion injury (IRI). There are currently no pharmacological interventions to limit hepatic IRI because the mechanisms by which steatosis leads to increased injury are unclear. To identify potential novel mediators of IRI, we used liquid chromatography and mass spectrometry to assess temporal changes in the hepatic lipidome in steatotic and non-steatotic livers after warm IRI in mice. Our untargeted analyses revealed distinct differences between the steatotic and non-steatotic response to IRI and highlighted dynamic changes in lipid composition with marked changes in glycerophospholipids. These findings enhance our knowledge of the lipidomic changes that occur following IRI and provide a foundation for future mechanistic studies. A better understanding of the mechanisms underlying such changes will lead to novel therapeutic strategies to combat IRI.

[Relation factor analysis for the short-term preservation of ipsilateral renal function after partial nephrectomy].

Objectives: To analyze the factors relative to the short-term preservation of ipsilateral renal function after partial nephrectomy. Methods: The clinical data of 83 patients who were treated with partial nephrectomy from December 2014 to December 2019 in the Department of Urology, Sun Yat-sen University Cancer Center were retrospectively analyzed. There were 54 males and 29 females, aging (M (IQR)) 49 (17) years (range: 27 to 74 years). The ischemia time in operation was 25 (18) minutes (range: 10 to 67 minutes). Emission computed tomography scan and CT scan were performed before (within 1 month) and after (3 to 12 months) surgery. The volume of the ipsilateral and contralateral kidney was measured on the basis of preoperative and postoperative CT scans. The glomerular filtration rate (GFR) specifically in each kidney was estimated by emission computed tomography. Recovery from ischemia is determined by the formula: GFR preservation/volume saved×100%. Linear regression was used to explore the factors ralative to the short-term preservation of ipsilateral renal function after partial nephrectomy. Results: The GFR preservation of the ipsilateral kidney was 80.9 (25.2) % (range: 31.0% to 109.4%). The volume loss of the kidney resulted in a decrease of 12.0% (5.8 ml/(min×1.96 m2)) of GFR, while the ischemic injury resulted in a decrease of 6.5% (2.5 ml/(min×1.96 m2)) of GFR. The volume saved from the ipsilateral kidney was 87.1 (12.9) % (range: 27.0% to 131.7%). Recovery from ischemia was 93.5 (17.5) % (range:44.3% to 178.3%). In multivariate analysis, GFR preservation of the ipsilateral kidney was significantly correlated with the volume saved of the ipsilateral kidney (ß=0.383, 95%CI: 0.144 to 0.622, P=0.002). It was not related to the ischemia time (ß=0.046, 95%CI:-0.383 to 0.475, P=0.831). Conclusion: In the condition of limited ischemic time, in the short term ipsilateral renal function after partial nephrectomy is mainly determined by the loss of kidney volume, while ischemic injury only plays a minor role.

Impact of Ischemia and Preservation Times on Survival in Transplant Recipients From After Circulatory Death Donors.

BACKGROUND: The limitation of ischemia times, which damages the organs and impacts transplant outcomes, is a drawback of controlled donation after circulatory death. METHODS: The aim of the study was to analyze the influence of preservation and ischemia times on overall survival and both censured graft survival and overall graft survival. This was an observational and retrospective study of patients undergoing liver transplantation with grafts from controlled donation after circulatory death between November 2013 and November 2022. RESULTS: Sixty-five patients were included in the study. Twenty percent (12 patients) developed early graft dysfunction according to Olthoff's classification, and 7 patients (11.6%) scored ≥7 points according to the Model for Early Allograft Function Scoring scale. Five patients (7.6%) met the criteria for primary graft failure. The retransplantation rate was 9.2% (6 cases). Fifty patients (76.9%) remained alive, and 15 patients (23.1%) died. When analyzing overall survival based on the main preservation and ischemia times, we observed that the best results occurred in the group with a functional warm ischemia time <12 minutes, with a survival rate at 1, 3, and 5 years of 95.8%, 87.1%, and 87.1%, respectively (P = .043). Regarding the analysis of censured graft survival based on the main preservation and ischemia times, we found that the worst results occurred in the group with a cold ischemia time ≥6 hours, with a survival rate of around 48% at 3 and 5 years (P = .047). CONCLUSIONS: High-risk patients have lower overall and graft survival in the short and long term in grafts from controlled donation after circulatory death.

Extended criteria liver donation after circulatory death with prolonged warm ischemia: a pilot experience of normothermic regional perfusion and no subsequent ex-situ machine perfusion.

BACKGROUND: Livers from controlled donation after circulatory death (cDCD) with very prolonged warm ischemic time (WIT) are regularly transplanted after abdominal normothermic regional perfusion (aNRP) plus ex-situ machine perfusion (MP). Considering aNRP as in-situ MP, we investigated whether the results of a pilot experience of extended criteria cDCD liver transplantation (LT) with prolonged WIT, with aNRP alone, were comparable to the best possible outcomes in low-risk cDCD LT. METHODS: Prospectively collected data on 24 cDCD LT, with aNRP alone, were analyzed. RESULTS: The median total and asystolic WIT were 51 and 25 min. Measures within benchmark cut-offs were: median duration of surgery (5.9 h); median intraoperative transfusions (3 units of red blood cells); need for renal replacement therapy (2/24 patients); median intensive care stay (3 days); key complications; overall morbidity, graft loss, and retransplantation up to 12 months; 12-month mortality (2/21 patients). The median hospital stay (33 days, due to logistics) and mortality up to 6 months (2/24 patients, due to graft-unrelated causes) exceeded benchmark thresholds. CONCLUSIONS: This pilot experience suggests that livers from cDCD with very prolonged WIT that appear viable during adequate quality aNRP may be safely transplanted, with no need for ex-situ MP, with considerable resource savings.

Parenchymal volume analysis to assess longitudinal functional decline following partial nephrectomy.

OBJECTIVE: To identify factors associated with longitudinal ipsilateral functional decline after partial nephrectomy (PN). PATIENTS AND METHODS: Of 1140 patients managed with PN (2012-2014), 349 (31%) had imaging/serum creatinine levels pre-PN, 1-12 months post-PN (new baseline), and >3 years later necessary for inclusion. Parenchymal-volume analysis was used to determine split renal function. Patients were grouped as having significant renal comorbidity (CohortSRC : diabetes mellitus with insulin-dependence or end-organ damage, refractory hypertension, or severe pre-existing chronic kidney disease) vs not having significant renal comorbidity (CohortNoSRC ) preoperatively. Multivariable regression was used to identify predictors of annual ipsilateral parenchymal atrophy and functional decline relative to new baseline values post-PN, after the kidney had healed. RESULTS: The median follow-up was 6.3 years with 87/226/36 patients having cold/warm/zero ischaemia. The median cold/warm ischaemia times were 32/22 min. Overall, the median tumour size was 3.0 cm. The preoperative glomerular filtration rate (GFR) and new baseline GFR (NBGFR) were 81 and 71 mL/min/1.73 m2 , respectively. After establishment of the NBGFR, the median loss of global and ipsilateral function was 0.7 and 0.4 mL/min/1.73 m2 /year, respectively, consistent with the natural ageing process. Overall, the median ipsilateral parenchymal atrophy was 1.2 cm3 /year and accounted for a median of 53% of the annual functional decline. Significant renal comorbidity, age, and warm ischaemia were independently associated with ipsilateral parenchymal atrophy (all P < 0.01). Significant renal comorbidity and ipsilateral parenchymal atrophy were independently associated with annual ipsilateral functional decline (both P < 0.01). Annual median ipsilateral parenchymal atrophy and functional decline were both significantly increased for CohortSRC compared to CohortNoSRC (2.8 vs 0.9 cm3 , P < 0.01 and 0.90 vs 0.30 mL/min/1.73 m2 /year, P < 0.01, respectively). CONCLUSIONS: Longitudinal renal function following PN generally follows the normal ageing process. Significant renal comorbidities, age, warm ischaemia, and ipsilateral parenchymal atrophy were the most important predictors of ipsilateral functional decline following establishment of NBGFR.

Limited non-linear impact of warm ischemia time on renal functional decline after partial nephrectomy: a propensity score-matched study.

OBJECTIVE: To quantificationally illustrate the impact of ischemia time (IT) on renal function decline after partial nephrectomy (PN), especially for patients with compromised baseline renal function (estimated glomerular filtration rate [eGFR] < 90 mL/min/1.73 m2). METHODS: Patients undergoing PN during 2014-2021 from a prospectively maintained database were reviewed. Propensity score matching (PSM) was employed to balance the possible covariates between patients with or without baseline compromised renal function. Specifically, the relationship of IT with postoperative renal function was illustrated. Two machine learning methods (logistic least absolute shrinkage and selection operator [LASSO] logistic regression and random forest) were applied to quantify the relative impact of each covariables. RESULTS: The average drop percent of eGFR was -10.9% (- 12.2%, - 9.0%). Multivariable Cox proportional regression and linear regression analyses identified five risk factors for renal function decline, namely RENAL Nephrometry Score (RNS), age, baseline eGFR, diabetes and IT (all p < 0.05). Specifically, the relationship of IT with postoperative functional decline emerged as non-linear, with an increase from 10-30 min and a plateau afterwards among patients with normal function (eGFR ≥ 90 mL/min/1.73 m2), whereas with an increase from 10 to 20 min and a plateau afterwards among patients with compromised function (eGFR < 90 mL/min/1.73 m2). Furthermore, the coefficient's path and random forest analysis revealed that the top two most important features were RNS and age. CONCLUSION: IT exhibits the secondarily non-linear relationship with postoperative renal function decline. Patients with compromised baseline renal function are less tolerant to ischemia damage. The use of a single cut-off interval of IT in the setting of PN is flawed.

Oxygen saturation during donor warm ischemia time and outcome of donation after circulatory death (DCD) liver transplantation with static cold storage: A review of 1114 cases.

The donor operation and the hemodynamics during declaration resulting in donor warm ischemia time have been linked to the outcomes in donation after circulatory death (DCD) liver transplantation (LT). Scrutiny of the donor hemodynamics at the time of withdrawal of life support concluded that a functional donor warm ischemia time may be associated with LT graft failure. Unfortunately, the definition for functional donor warm ischemia time has not reached a consensus-but has almost always incorporated time spent in a hypoxic state. Herein, we reviewed 1114 DCD LT cases performed at the 20 highest volume centers during 2014 and 2018. Donor hypoxia began within 3 minutes of withdrawal of life support for 60% of cases and within 10 minutes for 95% of cases. Graft survival was 88.3% at 1 year and 80.3% at 3 years. Scrutinizing the time spent under hypoxic conditions (oxygen saturation ≤ 80%) during the withdrawal of life support, we found an increasing risk of graft failure as hypoxic time increased from 0 to 16 minutes. After 16 minutes and up to 50 minutes, we did not find any increased risk of graft failure. In conclusion, after 16 minutes of time in hypoxia, the risk of graft failure in DCD LT did not increase. The current evidence suggests that an over-reliance on hypoxia time may lead to an unnecessary increase in DCD liver discard and may not be as useful for predicting graft loss after LT.

Evaluating a New Device for Reducing Second Warm Ischemia During Organ Transplantation in a Porcine Model of Kidney, Heart, and Pancreas Transplantation.

BACKGROUND: Second warm ischemia (SWI) injury between the completion of vascular anastomosis and graft reperfusion has been a longstanding issue in organ transplantation. This type of SWI injury is more severe in transplanted organs more sensitive to temperature changes. This study aimed to present the newly developed OrganPocket, an organ protector made from a proprietary elastomer material, and to demonstrate its efficacy in mitigating SWI injury in clinical kidney transplantation. METHODS: We used an ex vivo porcine organ model to evaluate OrganPocket. After removal, donor organs were immersed and cryopreserved in an organ preservation solution at 4°C before being placed in an OrganPocket. The organ graft and OrganPocket were held for 30 minutes in a 37°C environment mimicking intra-abdominal conditions while temperatures were recorded. Control organs were evaluated under the same conditions without an OrganPocket. In addition, we tested OrganPocket in an intra-abdominal porcine allograft transplant model. RESULTS: The control organ group temperature reached ≥16°C after 30 minutes, while the mean core temperature in the OrganPocket organ group remained at no more than 10°C. Despite an SWI time of approximately 30 minutes, the surface organ temperature upon removal of OrganPocket was 20°C. Cardiac grafts also exhibited a normal heartbeat after reperfusion. CONCLUSIONS: OrganPocket is the world's first device designed to prevent SWI and should also prove useful for heart transplantation.

Functional Assessment of Cardiac Arrest Hepatocytes and Effect of Mechanical Perfusion on Function in a Rat Model.

BACKGROUND: Hepatocyte transplantation has been reported to be useful for metabolic diseases and acute liver failure. However, the shortage of donors limits its widespread use. The use of livers from donors after circulatory death, which are currently unavailable for liver transplantation, may alleviate donor shortage. In this study, we investigated the effects of mechanical perfusion on cardiac arrest hepatocytes in a rat model using cardiac arrest donor livers, and we evaluated the function of cardiac arrest hepatocytes. METHODS: F344 rat hepatocytes isolated from livers removed during cardiac pulsation were compared with those isolated from livers removed after 30 minutes of warm ischemia after cardiac arrest. We then compared hepatocytes isolated from livers removed after 30 minutes of warm ischemia with those isolated after 30 minutes of mechanical perfusion before isolation. The yield per liver weight, ammonia removal capacity, and adenosine diphosphate/adenosine triphosphate ratio were evaluated. RESULTS: Thirty minutes of warm inhibition reduced hepatocyte yield but did not alter ammonia removal capacity and energy status. Mechanical perfusion increased hepatocyte yield and improved the adenosine diphosphate/adenosine triphosphate ratio after 30 minutes of warm inhibition. CONCLUSION: Thirty minutes of warm ischemic time may decrease isolated hepatocyte yield without degrading their function. If increased yields are obtained, livers from donors dying of cardiac arrest could be used for hepatocyte transplantation. The results also suggest that mechanical perfusion may positively affect the energy status of hepatocytes.

Effectiveness of Thermal Barrier Bag for Prolonged Vascular Anastomosis in Kidney Transplantation.

BACKGROUND: In kidney transplantation (KT), efforts to minimize rewarming and optimize anastomosis time during vascular anastomosis improve graft outcomes. We recently reported the safety and efficacy of a pouch-type thermal barrier bag (TBB) made of elastomer gel to reduce second-warm ischemic injury during vascular anastomosis. We aimed to examine the usefulness of the TBB in prolonged vascular anastomosis in KT performed by young transplant fellows. METHODS: Young transplant fellows performed KT under the supervision of certified transplant surgeons. The kidney graft was placed inside the TBB with an outlet for vessels and preserved during vascular anastomosis. A non-contact infrared thermometer measured the graft surface temperature before and after vascular anastomosis. After completion of the anastomosis, the TBB was manually slid out of the transplanted kidney and removed before graft reperfusion. Clinical data, including patient characteristics and perioperative variables, were collected. The primary endpoint was the median graft surface temperature at the end of the anastomosis. RESULTS: Ten living-donor kidney transplant recipients with a median age of 56.5 years (range, 40-69 years) underwent KT procedures performed by young transplant fellows. The median anastomosis time was 53 (43-67) min. At the end of anastomosis, the median graft surface temperature was 17.7°C (16.3-18.3°C); no serious adverse events or delayed graft function were observed. CONCLUSION: The TBB can keep transplanted kidneys at a low temperature even with prolonged vascular anastomosis time, thus contributing to the functional preservation of transplanted kidneys and stable transplant outcomes.

Insulating jackets thermally protect kidneys in an ex vivo model of second warm ischemia.

BACKGROUND: Kidney transplantation is the current optimal treatment for suitable patients with end-stage renal disease. The second warm ischemic time (SWIT) is known to negatively impact delayed graft function, and long-term graft survival, and methods are required to ameliorate the impacts of SWIT on transplantation outcomes. MATERIALS AND METHODS: This study primarily focused on determining the effect of a novel thermally insulating jacket on the thermal profile of the human kidney and quantifying the reduction in thermal energy experienced using this device (KPJ™). An ex vivo simulated transplantation model was developed to determine the thermal profiles of non-utilized human kidneys with and without KPJ™ (n = 5). Control kidney temperature profiles were validated against the temperature profiles of n = 10 kidneys during clinical kidney transplantation. RESULTS: Using the ex-vivo water bath model, the thermally insulated human kidney reached the 15°C metabolic threshold temperature at 44.5 ± 1.9 min (vs control: 17.3 ± 1.8 min (p = 0.00172)) and remained within the 18°C threshold until 53.3 ± 1.3 min (vs control: 20.9 ± 2.0 min (p = 0.002)). The specific heat capacity of KPJ™ protected kidney was four-fold compared to the control kidney. The clinical temperature audit, closely correlated with the water bath model, hence validating this ex-vivo human kidney transplant model. CONCLUSION: Intraoperative thermal protection is a simple and viable method of reducing the thermal injury that occurs during the SWIT and increasing the specific heat capacity of the system. Such technology could easily be translated into clinical kidney transplant practice.

Impact of Warm Ischemia on Acute Kidney Injury After Robotic Partial Nephrectomy Stratified by Baseline Kidney Function.

Objectives: To evaluate the differences in baseline chronic kidney disease (CKD) status in correlations between warm ischemic time (WIT) and acute kidney injury (AKI) or acute/chronic renal function change after robot-assisted partial nephrectomy (RAPN). Methods: This study retrospectively recruited 1290 patients from a multi-institutional RAPN database. The patients were grouped into four preoperative CKD categories: CKD Group 1 (CKDG1), CKD Group 2 (CKDG2), CKD Group 3a (CKDG3a), and CKD Group 3b (CKDG3b). The correlation between WIT and the probability of AKI was assessed according to the baseline CKD grade, together with changes in serum creatinine (sCr) at the postoperative maximum and chronic renal function. Results: AKI was not observed in the CKDG1 group. The probability of AKI at WIT = 30 minutes was 5.6% for CKDG2, 8.5% for CKDG3a, and 11.6% for CKDG3b (all p < 0.05). WIT was an independent predictor of AKI occurrence in the multivariate model for these three CKD groups. Significant weak correlations were observed between WIT and sCr change for all four groups, with R2 = 0.22 for CKDG1, R2 = 0.16 for CKDG2, R2 = 0.03 for CKDG3a, and R2 = 0.09 for ≥CKDG3b. For chronic renal function, correlations were significant in CKDG2, CKDG3a, and ≥CKDG3b, yet R2 was considered small in all cases (<0.1). Conclusions: The association between extended WIT and the probability of AKI increased in patients with more severe baseline CKD. The correlation between WIT and renal function was significant, yet clinically modest.

Every decade counts: a narrative review of functional recovery after partial nephrectomy.

OBJECTIVE: To provide a narrative review of the major advances regarding ischaemia and functional recovery after partial nephrectomy (PN), along with the ongoing controversies. METHODS: Key articles reflecting major advances regarding ischaemia and functional recovery after PN were identified. Special emphasis was placed on contributions that changed perspectives about surgical management. Priority was also placed on randomized trials of off-clamp vs on-clamp cohorts. RESULTS: A decade ago, 'Every minute counts' was published, showing strong correlations between duration of ischaemia and development of acute kidney injury (AKI) and chronic kidney disease after clamped PN. This reinforced perspectives that ischaemia was the main modifiable factor that could be addressed to improve functional outcomes and helped spur efforts towards reduced or zero ischaemia PN. These approaches were associated with strong functional recovery and some peri-operative risk, although they were generally safe in experienced hands. Further research demonstrated that, when parenchymal volume changes were incorporated into the analyses, ischaemia lost statistical significance, and percent parenchymal volume saved proved to be the main determinant. Cold ischaemia was confirmed to be highly protective, and limited warm ischaemia also proved to be safe. The reconstructive phase of PN, with avoidance of parenchymal devascularization, appears to be most important for functional outcomes. Randomized trials of on-clamp vs off-clamp PN have shown minimal impact of ischaemia on functional recovery. CONCLUSIONS: The past decade has witnessed great progress regarding functional recovery after PN, with many lessons learned. However, there are still unanswered questions, including: What is the threshold of warm ischaemia at which irreversible ischaemic injury begins to develop? Are some cohorts at increased risk for AKI or irreversible ischaemic injury? and Which patients should be prioritized for zero-ischaemia PN?

Pre-Ischemic Hypothermic Oxygenated Perfusion Alleviates Protective Molecular Markers of Ischemia-Reperfusion Injury in Rat Liver.

To expand the pool of organs, hypothermic oxygenated perfusion (HOPE), one of the most promising perfusion protocols, is currently performed after cold storage (CS) at transplant centers (HOPE-END). We investigated a new timing for HOPE, hypothesizing that performing HOPE before CS (HOPE-PRE) could boost mitochondrial protection allowing the graft to better cope with the accumulation of oxidative stress during CS. We analyzed liver injuries at 3 different levels. Histologic analysis demonstrated that, compared to classical CS (CTRL), the HOPE-PRE group showed significantly less ischemic necrosis compared to CTRL vs HOPE-END. From a biochemical standpoint, transaminases were lower after 2 hours of reperfusion in the CTRL vs HOPE-PRE group, which marked decreased liver injury. qPCR analysis on 37 genes involved in ischemia-reperfusion injury revealed protection in HOPE-PRE and HOPE-END compared to CTRL mediated through similar pathways. However, the CTRL vs HOPE-PRE group demonstrated an increased transcriptional level for protective genes compared to the CTRL vs HOPE-END group. This study provides insights on novel biomarkers that could be used in the clinic to better characterize graft quality improving transplantation outcomes.

Liver perfusion strategies: what is best and do ischemia times still matter?

PURPOSE OF REVIEW: This review describes recent developments in the field of liver perfusion techniques. RECENT FINDINGS: Dynamic preservation techniques are increasingly tested due to the urgent need to improve the overall poor donor utilization. With their exposure to warm ischemia, livers from donors after circulatory death (DCD) transmit additional risk for severe complications after transplantation. Although the superiority of dynamic approaches compared to static-cold-storage is widely accepted, the number of good quality studies remains limited. Most risk factors, particularly donor warm ischemia, and accepted thresholds are inconsistently reported, leading to difficulties to assess the impact of new preservation technologies. Normothermic regional perfusion (NRP) leads to good outcomes after DCD liver transplantation, with however short ischemia times. While randomized controlled trials (RCT) with NRP are lacking, results from the first RCTs with ex-situ perfusion were reported. Hypothermic oxygenated perfusion was shown to protect DCD liver recipients from ischemic cholangiopathy. In contrast, endischemic normothermic perfusion seems to not impact on the development of biliary complications, although this evidence is only available from retrospective studies. SUMMARY: Dynamic perfusion strategies impact posttransplant outcomes and are increasingly commissioned in various countries along with more evidence from RCTs. Transparent reporting of risk and utilization with uniform definitions is required to compare the role of different preservation strategies in DCD livers with prolonged ischemia times.

Warm ischemia time length during on-clamp partial nephrectomy: does it really matter?

BACKGROUND: The impact of warm ischemia time (WIT) on renal functional recovery remains controversial. We examined the length of WIT>30 min on the long-term renal function following on-clamp partial nephrectomy (PN). METHODS: Data from 23 centers for patients undergoing on-clamp PN between 2000 and 2018 were analyzed. We included patients with two kidneys, single tumor, cT1, minimum 1-year follow-up, and preoperative eGFR≥60 mL/min/1.73m2. Patients were divided into two groups according to WIT length: group I "WIT≤30 min" and group II "WIT>30 min." A propensity-score matched analysis (1:1 match) was performed to eliminate potential confounding factors between groups. We compared eGFR values, eGFR (%) preservation, eGFR decline, events of chronic kidney disease (CKD) upgrading, and CKD-free progression rates between both groups. Cox regression analysis evaluated WIT impact on upgrading of CKD stages. RESULTS: The primary cohort consisted of 3526 patients: group I (N.=2868) and group II (N.=658). After matching the final cohort consisted of 344 patients in each group. At last follow-up, there were no significant differences in median eGFR values at 1, 3, 5, and 10 years (P>0.05) between the matched groups. In addition, the median eGFR (%) preservation and absolute eGFR change were similar (89% in group I vs. 87% in group II, P=0.638) and (-10 in group I vs. -11 in group II, P=0.577), respectively. The 5 years new-onset CKD-free progression rates were comparable in the non-matched groups (79% in group I vs. 81% in group II, log-rank, P=0.763) and the matched groups (78.8% in group I vs. 76.3% in group II, log-rank, P=0.905). Univariable Cox regression analysis showed that WIT>30 min was not a predictor of overall CKD upgrading (HR:0.953, 95%CI 0.829-1.094, P=0.764) nor upgrading into CKD stage ≥III (HR:0.972, 95%CI 0.805-1.173, P=0.764). Retrospective design is a limitation of our study. CONCLUSIONS: Our analysis based on a large multicenter international cohort study suggests that WIT length during PN has no effect on the long-term renal function outcomes in patients having two kidneys and preoperative eGFR≥60 mL/min/1.73m2.

Improving Liver Graft Function Using CD47 Blockade in the Setting of Normothermic Machine Perfusion.

BACKGROUND: Toward the goal of using more livers for transplantation, transplant centers are looking to increase the use of organs from "marginal" donors. Livers from these donors, however, have been shown to be more susceptible to preservation and reperfusion injury. METHODS: Using a porcine model of donation after circulatory death, we studied the use of antibody-mediated CD47 blockade to further improve liver graft function undergoing normothermic machine perfusion. Livers from 20 pigs (5 per group) were brought under either 30 or 60 min of warm ischemia time followed by the administration of CD47 monoclonal antibody (CD47mAb) treatment or immunoglobulin G control antibodies and 6 h of normothermic extracorporeal liver perfusion. RESULTS: After 6 h of normothermic extracorporeal liver perfusion, CD47mAb-treated livers with 30 or 60 min warm ischemia time had significantly lower alanine transaminase levels and higher bile production compared with their respective control groups. Blockade of the CD47 signaling pathway resulted in significantly lower thrombospondin-1 protein levels, lower expression of caspase-3, and higher expression of phosphorylated extracellular signal-regulated kinase. CONCLUSIONS: These findings suggested that CD47mAb treatment decreases ischemia/reperfusion injury through CD47/thrombospondin-1 signaling downregulation and the presence of necrosis/apoptosis after reperfusion and could increase liver regeneration during normothermic perfusion of the liver.