Timing Considerations for Sleeve Gastrectomy in Kidney Transplant Patients: A Single Center Evaluation.

Current scientific literature is deficient in detailing the optimal timing for conducting bariatric surgery in relation to kidney transplantation. In this study, we performed a retrospective evaluation of kidney transplant recipients with BMI >35 kg/m2. It aimed to provide data on those who received both sleeve gastrectomy (SG) and kidney transplantation (KT) simultaneously, as well as on patients who underwent SG and KT at different times, either before or after. In addition, the acceptance levels of the bariatric surgery among different scenarios were assessed. Our findings demonstrated that combined KT and SG led to successful weight loss, in contrast to undergoing kidney transplant alone, while maintaining comparable rates of graft and patient survival. Weight loss was similar between recipients who had a combined operation and those who underwent SG following the transplant. Additionally, over a median time frame of 1.7 years, patients who underwent SG before KT exhibited a statistically significant reduction in BMI at the time of the transplant. Notably, our study highlights that patients offered the combined procedure were significantly more likely to undergo SG compared to those for whom SG was presented at a different operative time than the transplant.

Safety and graft outcome of right retroperitoneal laparoscopic donor nephrectomy for living donor kidney transplantation: A comparison with left retroperitoneal laparoscopic donor nephrectomy.

INTRODUCTION: The left kidney is often preferred for living donor kidney transplantation because of its anatomical advantages. However, the right kidney may be procured due to donor conditions. Few studies have assessed the safety and graft outcome of right retroperitoneal laparoscopic donor nephrectomy (RDN). This study aimed to compare the outcomes between right and left RDN with respect to donor outcome and the graft function of recipients. METHODS: This retrospective study included 230 consecutive living donor kidney transplants performed at our institution between May 2019 and March 2023. We reviewed the outcomes of kidney transplant in the right and left kidneys after RDN. RESULTS: A total of 230 living donor kidney transplants were performed, with 32 donors receiving right RDN (right RDN group) and 198 donors receiving left RDN (left RDN group). The renal veins and ureters were significantly shorter in the right RDN group than in the left RDN group (both p < .001). Donor operation and warm ischemia time were significantly longer in the right RDN group than in the left RDN group (p = .012 and p < .001, respectively). None of the groups exhibited any cases of delayed graft function owing to donor-related reasons. Perioperative changes in the estimated glomerular filtration rate of recipients and death-censored graft survival were not significantly different between the two groups. CONCLUSIONS: In RDN, the outcomes of right donor nephrectomy were comparable to those of left donor nephrectomy in terms of donor safety and recipient renal function.

Intensive Surveillance of Porcine-Rhesus Kidney Xenotransplant Using Different Ultrasound Techniques.

BACKGROUND: Significant progress has been made in kidney xenotransplantation in the past few years, and this field is accelerating towards clinical translation. Therefore, surveillance of the xenograft with appropriate tools is of great importance. Ultrasonography has been widely used in kidney allotransplantation and served as an economical and non-invasive method to monitor the allograft. However, questions remain whether the ultrasonographic criteria established for human kidney allograft could also be applied in xenotransplantation. METHODS: In the current study, we established a porcine-rhesus life sustaining kidney xenotransplantation model. The xenograft underwent intensive surveillance using gray-scale, colorful Doppler ultrasound as well as 2D shear wave elastography. The kidney growth, blood perfusion, and cortical stiffness were measured twice a day. These parameters were compared with the clinical data including urine output, chemistry, and pathological findings. RESULTS: The observation continued for 16 days after transplantation. Decline of urine output and elevated serum creatinine were observed on POD9 and biopsy proven antibody-mediated rejection was seen on the same day. The xenograft underwent substantial growth, with the long axis length increased by 32% and the volume increased by threefold at the end of observation. The resistive index of the xenograft arteries elevated in response to rejection, together with impaired cortical perfusion, while the peak systolic velocity (PSV) was not compromised. The cortical stiffness also increased along with rejection. CONCLUSION: In summary, the ultrasound findings of kidney xenograft shared similarities with those in allograft but possessed some unique features. A modified criteria needs to be established for further application of ultrasound in kidney xenotransplantation.

The impact of preservation solutions for static cold storage on kidney transplantation outcomes: Results of a Brazilian nationwide multicenter study.

This study evaluated the current practices of selecting cold storage preservation solutions in Brazil and their impact on delayed graft function (DGF) incidence and 1-year outcomes in kidney transplant recipients. A retrospective cohort study was conducted, including 3,134 brain-dead deceased donor kidney transplants performed between 2014 and 2015 in 18 Brazilian centers. The most commonly used preservation solution was Euro-collins (EC, 55.4%), followed by Histidine-tryptophan-ketoglutarate (HTK, 30%) and Institut Georges Lopez (IGL-1, 14.6%). The incidence of DGF was 54.4%, with 11.7% of patients requiring dialysis for more than 14 days, indicating prolonged DGF. Upon adjusting for confounding variables, HTK demonstrated a significantly lower risk of DGF than EC (OR 0.7350.82500.926), as did IGL-1 (OR 0.6050.7120.837). Similar protective effects were observed for prolonged DGF when comparing HTK (OR 0.4780.5990.749) and IGL-1 (OR 0.4780.6810.749) against EC. No significant association was found between preservation solutions and 1-year death-censored graft survival. In conclusion, EC was the most frequently used cold storage perfusion solution, demonstrating a higher incidence and duration of DGF compared with HTK and IGL-1, but with no impact on 1-year graft survival.

Access to robotic assisted kidney transplant for recipients: a systematic review and call for reporting standards.

Robot-assisted kidney transplantation (RAKT) is a relatively novel, minimally invasive option for kidney transplantation. However, clarity on recipient selection in the published literature is lacking thereby significantly limiting interpretation of safety and other outcomes. This systematic review aimed to identify and synthesize the data on selection of RAKT recipients, compare the synthesized data to kidney transplant recipients across the USA, and explore geographical clusters of availability of RAKT. Systematic literature review, in accordance with PRISMA, via OVID MEDLINE, Embase, and Web of science from inception to March 5, 2023. All data entry double blinded and quality via Newcastle Ottawa Scale. 44 full-text articles included, encompassing approximately 2402 kidney transplant recipients at baseline but with considerable suspicion for overlap across publications. There were significant omissions of information across studies on patient selection for RAKT and/or analysis. Overall, the quality of studies was very low. Given suspicion of overlap across studies, it is difficult to determine how many RAKT recipients received living (LD) versus deceased donor (DD) organs, but a rough estimate suggests 89% received LD. While the current RAKT literature provides preliminary evidence on safety, there are significant omissions in reporting on patient selection for RAKT which limits interpretation of findings. Two recommendations: (1) international consensus is needed for reporting guidelines when publishing RAKT data and (2) larger controlled trials consistently reporting recipient characteristics are needed to clearly determine selection, safety, and outcomes across both LD and DD recipients.

Follow-up After Donor Nephrectomy in Living Kidney Donors: How to Manage Living Kidney Donors Postoperatively.

BACKGROUND/AIM: This study investigated the follow-up rate of living kidney donors and explored the factors related to continuous follow-up and remnant renal function, enabling the optimal management of living kidney donors. PATIENTS AND METHODS: We retrospectively evaluated 180 living kidney donors who underwent donor nephrectomies at our institute. Clinical information was obtained from medical charts, and remnant renal function was defined as the estimated glomerular filtration rate 12 months after donor nephrectomy. RESULTS: Overall, 6/180 donors (3.3%) were lost to follow-up within a year, and the follow-up rate gradually declined yearly. Independent risk factors for loss to follow-up included a follow-up period <60 months and graft survival of the recipient (p=0.002 and p=0.043, respectively). Recipient survival was correlated with loss to follow-up; however, this was not significant (p=0.051). Regarding remnant renal function, age ≥60 years, preoperative estimated glomerular filtration rate <74 ml/min/1.73 m2, and a Δsingle-kidney estimated glomerular filtration rate <9.3 ml/min/1.73m2 were independent risk factors for poorly preserved remnant renal function (p=0.036, p<0.0001, and p<0.0001, respectively). Using propensity score matching to adjust for preoperative factors, a Δsingle-kidney estimated glomerular filtration rate <9.3 ml/min/1.73 m2 was the only significant postoperative factor for poorly preserved remnant renal function (p=0.023). CONCLUSION: An increased 5-year follow-up rate could lead to an increase in long-term follow-up, and recipient prognosis may be correlated with the living kidney donor follow-up status. Furthermore, Δsingle-kidney estimated glomerular filtration rate was identified as a factor for establishing the optimal precision follow-up management of living kidney donors.

Comparison of preemptive and non-preemptive kidney transplantation outcomes in children aged <6 years.

We aimed to compare the outcomes of pediatric kidney transplantation (KT) between preemptive KT (PEKT) and non-PEKT in children aged < 6 years. Seventy-four pediatric recipients aged < 6 years who underwent KT were divided into the PEKT and non-PEKT groups. They were retrospectively evaluated for patient and graft survival, graft function, growth, and cytomegalovirus (CMV) infection. Comparison of the groups (PEKT, n = 14; non-PEKT, n = 60) revealed no significant differences between them in terms of distribution of sex, age, weight, primary disease, or population of pre-transplant CMV immunoglobulin G-positive patients. The median estimated glomerular filtration rate before KT in the PEKT and non-PEKT groups was 11.4 and 7.3 (mL/min/1.73 m2) (P < .001), respectively, and the median duration of dialysis was 2.7 years in the non-PEKT group. Graft survival at 5 years was 100% and 95% in the PEKT and non-PEKT groups, respectively (P = .634). One patient in the non-PEKT group had vascular complications, with subsequent early graft loss. Incidence of CMV infection was significantly lower in the PEKT group (P = .044). There were no significant differences in post-transplant estimated glomerular filtration rate, acute rejection, or growth. The height standard deviation score showed catch-up growth after KT in both groups. There was no significant difference in transplant outcomes in recipients aged < 6 years, with or without pre-transplant dialysis, except for the incidence of CMV infection. Therefore, PEKT in younger children should be performed aggressively by experienced multi-disciplinary teams.

Robotic performance metrics model fellow proficiency in living donor nephrectomy.

We investigated the use of robotic objective performance metrics (OPM) to predict number of cases to proficiency and independence among abdominal transplant fellows performing robot-assisted donor nephrectomy (RDN). 101 RDNs were performed by 5 transplant fellows from September 2020 to October 2023. OPM included fellow percent active control time (%ACT) and handoff counts (HC). Proficiency was defined as ACT ≥ 80% and HC ≤ 2, and independence as ACT ≥ 99% and HC ≤ 1. Case number was significantly associated with increasing fellow %ACT, with proficiency estimated at 14 cases and independence at 32 cases (R2 = 0.56, p < 0.001). Similarly, case number was significantly associated with decreasing HC, with proficiency at 18 cases and independence at 33 cases (R2 = 0.29, p < 0.001). Case number was not associated with total active console time (p = 0.91). Patient demographics, operative characteristics, and outcomes were not associated with OPM, except for donor estimated blood loss (EBL), which positively correlated with HC. Abdominal transplant fellows demonstrated proficiency at 14-18 cases and independence at 32-33 cases. Total active console time remained unchanged, suggesting that increasing fellow autonomy does not impede operative efficiency. These findings may serve as a benchmark for training abdominal transplant surgery fellows independently and safely in RDN.

Robotic versus laparoscopic versus open nephrectomy for live kidney donors.

BACKGROUND: Waiting lists for kidney transplantation continue to grow. Live kidney donation significantly reduces waiting times and improves long-term outcomes for recipients. Major disincentives to potential kidney donors are the pain and morbidity associated with surgery. This is an update of a review published in 2011. OBJECTIVES: To assess the benefits and harms of open donor nephrectomy (ODN), laparoscopic donor nephrectomy (LDN), hand-assisted LDN (HALDN) and robotic donor nephrectomy (RDN) as appropriate surgical techniques for live kidney donors. SEARCH METHODS: We contacted the Information Specialist and searched the Cochrane Kidney and Transplant Register of Studies up to 31 March 2024 using search terms relevant to this review. Studies in the Register are identified through searches of CENTRAL, MEDLINE, and EMBASE, conference proceedings, the International Clinical Trials Registry Platform (ICTRP) Search Portal, and ClinicalTrials.gov. SELECTION CRITERIA: Randomised controlled trials (RCTs) comparing LDN with ODN, HALDN, or RDN were included. DATA COLLECTION AND ANALYSIS: Two review authors independently screened titles and abstracts for eligibility, assessed study quality, and extracted data. We contacted study authors for additional information where necessary. Summary estimates of effect were obtained using a random-effects model, and results were expressed as risk ratios (RR) and their 95% confidence intervals (CI) for dichotomous outcomes and mean difference (MD) or standardised mean difference (SMD) and 95% CI for continuous outcomes. Confidence in the evidence was assessed using the Grading of Recommendations Assessment, Development and Evaluation (GRADE) approach. MAIN RESULTS: Thirteen studies randomising 1280 live kidney donors to ODN, LDN, HALDN, or RDN were included. All studies were assessed as having a low or unclear risk of bias for selection bias. Five studies had a high risk of bias for blinding. Seven studies randomised 815 live kidney donors to LDN or ODN. LDN was associated with reduced analgesia use (high certainty evidence) and shorter hospital stay, a longer procedure and longer warm ischaemia time (moderate certainty evidence). There were no overall differences in blood loss, perioperative complications, or need for operations (low or very low certainty evidence). Three studies randomised 270 live kidney donors to LDN or HALDN. There were no differences between HALDN and LDN for analgesia requirement, hospital stay (high certainty evidence), duration of procedure (moderate certainty evidence), blood loss, perioperative complications, or reoperations (low certainty evidence). The evidence for warm ischaemia time was very uncertain due to high heterogeneity. One study randomised 50 live kidney donors to retroperitoneal ODN or HALDN and reported less pain and analgesia requirements with ODN. It found decreased blood loss and duration of the procedure with HALDN. No differences were found in perioperative complications, reoperations, hospital stay, or primary warm ischaemia time. One study randomised 45 live kidney donors to LDN or RDN and reported a longer warm ischaemia time with RDN but no differences in analgesia requirement, duration of procedure, blood loss, perioperative complications, reoperations, or hospital stay. One study randomised 100 live kidney donors to two variations of LDN and reported no differences in hospital stay, duration of procedure, conversion rates, primary warm ischaemia times, or complications (not meta-analysed). The conversion rates to ODN were 6/587 (1.02%) in LDN, 1/160 (0.63%) in HALDN, and 0/15 in RDN. Graft outcomes were rarely or selectively reported across the studies. There were no differences between LDN and ODN for early graft loss, delayed graft function, acute rejection, ureteric complications, kidney function or one-year graft loss. In a meta-regression analysis between LDN and ODN, moderate certainty evidence on procedure duration changed significantly in favour of LDN over time (yearly reduction = 7.12 min, 95% CI 2.56 to 11.67; P = 0.0022). Differences in very low certainty evidence on perioperative complications also changed significantly in favour of LDN over time (yearly change in LnRR = 0.107, 95% CI 0.022 to 0.192; P = 0.014). Various different combinations of techniques were used in each study, resulting in heterogeneity among the results. AUTHORS' CONCLUSIONS: LDN is associated with less pain compared to ODN and has comparable pain to HALDN and RDN. HALDN is comparable to LDN in all outcomes except warm ischaemia time, which may be associated with a reduction. One study reported kidneys obtained during RDN had greater warm ischaemia times. Complications and occurrences of perioperative events needing further intervention were equivalent between all methods.

Robotic living donor nephrectomy is associated with reduced post-operative opioid use compared to hand-assisted laparoscopic approach.

BACKGROUND: Robotic donor nephrectomy (RDN) has emerged as a safe alternative to laparoscopic donor nephrectomy (LDN). Having previously demonstrated comparable efficacy, this study aims to examine postoperative analgesia use (opioid and non-opioid) in the two groups. METHODS: We conducted a retrospective review of 300 living donor nephrectomies performed at our center, comparing 150 RDN's with a contemporary cohort of 150 hand-assisted LDN's. In addition to clinical and demographic information, data on postoperative inpatient opioid and non-opioid analgesia (from patient's arrival to the surgical floor after surgery till the time of discharge) was collected. Opioid dosages were standardized by conversion to morphine milligram equivalents (MME). All patients were managed post-operatively under a standardized ERAS pathway for living donor nephrectomy patients. RESULTS: There were no significant differences in donor age, gender, and BMI between RDN and LDN groups. Total post-operative opioid use (MME's) was significantly lower in RDN patients (RDN 27.1 vs. LDN 46.3; P < 0.0001). Breakdown of opioid use with post-operative (POD) day demonstrated significantly lower use in RDN group on POD1 (RDN 8.6 vs. LDN 17.0; P < 0.05), and POD2 (RDN 3.9 vs LDN 10; P < 0.05). RDN patients had a shorter post-operative length of stay (LOS) (RDN 1.69 days vs. LDN 1.98; P = 0.0003). There were no differences between groups in non-opioid medication use, complications, and readmission rates. CONCLUSION: RDN has comparable safety to hand-assist LDN and offers additional benefits of lower postoperative opioid requirement and a shorter hospital LOS.

Patient sequentially receives a left ventricular assist device and a porcine kidney transplant.

As a second porcine kidney xenotransplant case in a human recipient to date, this breakthrough technology offers an option even to patients with complex multiorgan failures, who may not be candidates for a conventional organ transplant.

Delivery of Mesenchymal Stem Cells during Hypothermic Machine Perfusion in a Translational Kidney Perfusion Study.

In transplantation, hypothermic machine perfusion (HMP) has been shown to be superior to static cold storage (SCS) in terms of functional outcomes. Ex vivo machine perfusion offers the possibility to deliver drugs or other active substances, such as Mesenchymal Stem Cells (MSCs), directly into an organ without affecting the recipient. MSCs are multipotent, self-renewing cells with tissue-repair capacities, and their application to ameliorate ischemia- reperfusion injury (IRI) is being investigated in several preclinical and clinical studies. The aim of this study was to introduce MSCs into a translational model of hypothermic machine perfusion and to test the efficiency and feasibility of this method. Methods: three rodent kidneys, six porcine kidneys and three human kidneys underwent HMP with 1-5 × 106 labelled MSCs within respective perfusates. Only porcine kidneys were compared to a control group of 6 kidneys undergoing HMP without MSCs, followed by mimicked reperfusion with whole blood at 37 °C for 2 h for all 12 kidneys. Reperfusion perfusate samples were analyzed for levels of NGAL and IL-ß by ELISA. Functional parameters, including urinary output, oxygen consumption and creatinine clearance, were compared and found to be similar between the MSC treatment group and the control group in the porcine model. IL-1ß levels were higher in perfusate and urine samples in the MSC group, with a median of 285.3 ng/mL (IQR 224.3-407.8 ng/mL) vs. 209.2 ng/mL (IQR 174.9-220.1), p = 0.51 and 105.3 ng/mL (IQR 71.03-164.7 ng/mL) vs. 307.7 ng/mL (IQR 190.9-349.6 ng/mL), p = 0.16, respectively. MSCs could be traced within the kidneys in all models using widefield microscopy after HMP. The application of Mesenchymal Stem Cells in an ex vivo hypothermic machine perfusion setting is feasible, and MSCs can be delivered into the kidney grafts during HMP. Functional parameters during mimicked reperfusion were not altered in treated kidney grafts. Changes in levels of IL-1ß suggest that MSCs might have an effect on the kidney grafts, and whether this leads to a positive or a negative outcome on IRI in transplantation needs to be determined in further experiments.

Transplant Nephrectomy: A Comparative Study of Timing and Techniques in a Single Institution.

BACKGROUND Transplant nephrectomy (TN) has historically been associated with high morbidity and mortality rates. Our objective is to share our own experience and compare indications and surgical outcomes between early and late TN and intracapsular (ICAN) and extracapsular allograft nephrectomy (ECAN) techniques. MATERIAL AND METHODS Our study included all 69 TN procedures performed between January 2010 and February 2021. Of these, 17 TN procedures were performed within the first 60 days after transplantation (referred to as 'early'), while the remaining 52 procedures were performed later ('late'). Within the late allograft nephrectomy (AN) group, we compared the outcomes of intracapsular (ICAN) and extracapsular (ECAN) techniques. We conducted a statistical analysis using the chi-square test and the 2-sample t test. RESULTS The primary indication for early TN was surgical transplant complications (94.1%), with 58.8% of these cases requiring emergency surgery. Morbidity (major complications) occurred in 47.1% of cases, and mortality was 5.9%. In contrast, graft intolerance syndrome was the leading indication for late TN (76.9%), with elective surgery performed in 88.5% of cases. Morbidity (major complications) occurred in 11.5% of cases, and mortality was 3.8%. Within the late TN group, 82.7% of cases were treated with ICAN and 17.3% with ECAN. Blood transfusion was required during surgery in 17.3% of cases, with no significant difference between the groups. Multivariate logistic regression analysis revealed that the timing of surgery was the only statistically significant predictor of complication occurrence. CONCLUSIONS Our data suggest that TN can be performed with relatively low morbidity. However, early TN remains the only independent risk factor for developing adverse outcomes.

Remote ischemic conditioning may improve graft function following kidney transplantation: a systematic review and meta-analysis with trial sequential analysis.

BACKGROUND: Remote ischemic conditioning (RIC) has the potential to benefit graft function following kidney transplantation by reducing ischemia-reperfusion injury; however, the current clinical evidence is inconclusive. This meta-analysis with trial sequential analysis (TSA) aimed to determine whether RIC improves graft function after kidney transplantation. METHODS: A comprehensive search was conducted on PubMed, Cochrane Library, and EMBASE databases until June 20, 2023, to identify all randomized controlled trials that examined the impact of RIC on graft function after kidney transplantation. The primary outcome was the incidence of delayed graft function (DGF) post-kidney transplantation. The secondary outcomes included the incidence of acute rejection, graft loss, 3- and 12-month estimated glomerular filtration rates (eGFR), and the length of hospital stay. Subgroup analyses were conducted based on RIC procedures (preconditioning, perconditioning, or postconditioning), implementation sites (upper or lower extremity), and graft source (living or deceased donor). RESULTS: Our meta-analysis included eight trials involving 1038 patients. Compared with the control, RIC did not significantly reduce the incidence of DGF (8.8% vs. 15.3%; risk ratio = 0.76, 95% confidence interval [CI], 0.48-1.21, P = 0.25, I2 = 16%), and TSA results showed that the required information size was not reached. However, the RIC group had a significantly increased eGFR at 3 months after transplantation (mean difference = 2.74 ml/min/1.73 m2, 95% CI: 1.44-4.05 ml/min/1.73 m2, P < 0.0001, I2 = 0%), with a sufficient evidence suggested by TSA. The secondary outcomes were comparable between the other secondary outcomes. The treatment effect of RIC did not differ between the subgroup analyses. CONCLUSION: In this meta-analysis with trial sequential analysis, RIC did not lead to a significant reduction in the incidence of DGF after kidney transplantation. Nonetheless, RIC demonstrated a positive correlation with 3-month eGFR. Given the limited number of patients included in this study, well-designed clinical trials with large sample sizes are required to validate the renoprotective benefits of RIC. TRIAL REGISTRATION: This systematic review and meta-analysis was registered at the International Prospective Register of Systematic Reviews (Number CRD42023464447).

Mouse kidney transplantation model: Three novel methods. / å°é¼ è‚¾ç§»æ¤æ¨¡åž‹ï¼š3种创新术式（英文）.

OBJECTIVES: The mouse kidney transplantation model presents challenges in terms of surgical difficulty and low success rate, making it difficult to master. This study aims to provide a crucial model for transplantation immunology research by modifying and developing novel techniques for mouse kidney transplantation. METHODS: A total of 57 pairs of mice were used to establish and compare the modified and innovative surgical techniques for mouse kidney transplantation. Three different surgical models were established, including the abdominal suture technique for orthotopic kidney transplantation, the abdominal cuff technique for orthotopic kidney transplantation, and the cervical cuff technique for ectopic kidney transplantation. BALB/c or C57BL/6 male mice, aged 8 to 12 weeks and weighed 20 to 25 g with specified pathogen free-grade were served as the donor mice or the recipient mice. The surgical technique characteristics, key surgical times, complications, and pathological examination in the early postoperative period were summarized and compared. RESULTS: Three different surgical models of mouse kidney transplantation were successfully established. The comparison of warm ischemic time for the 3 groups of mice showed no statistical significance (P=0.510 4). The abdominal suture group had the shortest total operation time of the donor compared with the abdominal cuff group and the cervical cuff group [(18.3±3.6) min vs (26.2±4.7) min and (22.8±2.5) min; both P<0.000 1]. There was a significant difference in cold ischemia time among the 3 groups (all P<0.000 1), with (60.8±4.1) min in the cervical cuff group, (43.3±5.0) min in the abdominal suture group, and (88.8±6.7) min in the abdominal cuff group. Due to different anastomosis methods, the cervical cuff group had the shortest time [(17.6±2.7) min], whereas the abdominal cuff group had the longest time [(38.8±5.4) min]. The total operation time for the recipients showed significant differences (P<0.000 1), with the abdominal suture group having the shortest time [(44.0±6.9) min], followed by the cervical cuff group [(64.1±5.2) min], and the abdominal cuff group [(80.0±6.0) min] being the longest. In the 32 mice of the abdominal suture group, there were 6 with intraoperative bleeding, including 1 arterial intimal injury bleeding and 5 with bleeding after vessel opening. Six mice had ureteral complications, including ureteral bladder anastomotic stenosis, necrosis, and renal pelvis dilation. Two mice had postoperative abdominal infections. In the abdominal cuff group, there was no intraoperative bleeding, but 6 mice showed mild arterial stenosis and 5 showed venous stenosis, 4 arterial injury, 4 arterial thrombosis, and 2 ureteral complications. No postoperative infections occurred in the mice. In the cervical cuff group, no intraoperative bleeding, arterial intimal injury, arterial/venous stenosis, or thrombosis were found in 13 mice. Five mice had ureteral complications, including ureteral necrosis and infection, which were the main complications in the cervical cuff group. The renal function in mice of the 3 groups remained stable 7 days after surgery. Hematoxylin and eosin staining and periodic acid-Schiff staining showed no significant differences in terms of acute rejection among the 3 surgical methods (all P>0.05). CONCLUSIONS: All 3 surgical methods are able to successfully establish mouse kidney transplantation models, with no significant differences observed in the short-term graft survival and acute rejection. The modified abdominal suture technique and abdominal cuff technique have their respective advantages in research applications. The novel cervical cuff technique for ectopic kidney transplantation model is relatively simple to be prepared and causes less trauma to the mice, providing more options for studies involving xenotransplantation, secondary transplantation, and local lymphatic drainage. However, the difficulty in harvesting the donor kidney and the high incidence of ureteral infections need further validation in long-term survival. This study holds important reference value for choosing the type of mouse kidney transplantation model for different research needs.

Late graft failure of pig-to-rhesus renal xenografts has features of glomerulopathy and recipients have anti-swine leukocyte antigen class I and class II antibodies.

Prolonged survival in preclinical renal xenotransplantation demonstrates that early antibody mediated rejection (AMR) can be overcome. It is now critical to evaluate and understand the pathobiology of late graft failure and devise new means to improve post xenograft outcomes. In renal allotransplantation the most common cause of late renal graft failure is transplant glomerulopathy-largely due to anti-donor MHC antibodies, particularly anti-HLA DQ antibodies. We evaluated the pig renal xenograft pathology of four long-surviving (>300 days) rhesus monkeys. We also evaluated the terminal serum for the presence of anti-SLA class I and specifically anti-SLA DQ antibodies. All four recipients had transplant glomerulopathy and expressed anti-SLA DQ antibodies. In one recipient tested for anti-SLA I antibodies, the recipient had antibodies specifically reacting with two of three SLA I alleles tested. These results suggest that similar to allotransplantation, anti-MHC antibodies, particularly anti-SLA DQ, may be a barrier to improved long-term xenograft outcomes.

Strategies for choosing the best living donor: A review of the literature and a proposal of a decision-making paradigm.

Transplantation remains the gold-standard treatment for pediatric end-stage kidney disease. While living donor transplant is the preferred option for most pediatric patients, it is not the right choice for all. For those who have the option to choose between deceased donor and living donor transplantation, or from among multiple potential living donors, the transplant clinician must weigh multiple dynamic factors to identify the most optimal donor. This review will cover the key considerations when choosing between potential living donors and will propose a decision-making algorithm.

Fetal Kidney Grafts and Organoids from Microminiature Pigs: Establishing a Protocol for Production and Long-Term Cryopreservation.

Fetal organs and organoids are important tools for studying organ development. Recently, porcine organs have garnered attention as potential organs for xenotransplantation because of their high degree of similarity to human organs. However, to meet the prompt demand for porcine fetal organs by patients and researchers, effective methods for producing, retrieving, and cryopreserving pig fetuses are indispensable. Therefore, in this study, to collect fetuses for kidney extraction, we employed cesarean sections to preserve the survival and fertility of the mother pig and a method for storing fetal kidneys by long-term cryopreservation. Subsequently, we evaluated the utility of these two methods. We confirmed that the kidneys of pig fetuses retrieved by cesarean section that were cryopreserved for an extended period could resume renal growth when grafted into mice and were capable of forming renal organoids. These results demonstrate the usefulness of long-term cryopreserved fetal pig organs and strongly suggest the effectiveness of our comprehensive system of pig fetus retrieval and fetal organ preservation, thereby highlighting its potential as an accelerator of xenotransplantation research and clinical innovation.