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BACKGROUND:Xenografts from genetically modified pigs have become one of the most promising solutions to the dearth of human organs available for transplantation. The challenge in this model has been hyperacute rejection. To avoid this, pigs have been bred with a knockout of the alpha-1,3-galactosyltransferase gene and with subcapsular autologous thymic tissue. METHODS:We transplanted kidneys from these genetically modified pigs into two brain-dead human recipients whose circulatory and respiratory activity was maintained on ventilators for the duration of the study. We performed serial biopsies and monitored the urine output and kinetic estimated glomerular filtration rate (eGFR) to assess renal function and xenograft rejection. RESULTS:in Recipient 2. In both recipients, the creatinine level, which had been at a steady state, decreased after implantation of the xenograft, from 1.97 to 0.82 mg per deciliter in Recipient 1 and from 1.10 to 0.57 mg per deciliter in Recipient 2. The transplanted kidneys remained pink and well-perfused, continuing to make urine throughout the study. Biopsies that were performed at 6, 24, 48, and 54 hours revealed no signs of hyperacute or antibody-mediated rejection. Hourly urine output with the xenograft was more than double the output with the native kidneys. CONCLUSIONS:Genetically modified kidney xenografts from pigs remained viable and functioning in brain-dead human recipients for 54 hours, without signs of hyperacute rejection. (Funded by Lung Biotechnology.).

Background/UNASSIGNED:The shortage of transplantable organs has led to increased utilization of kidneys that may be particularly vulnerable to ischemia-reperfusion injury (IRI) and delayed graft function (DGF). Kidneys from donation after circulatory death (DCD) donors have additional IRI from donor procurement that results in increased risk of DGF. Verapamil may reduce IRI in kidney allografts when given at the time of organ reperfusion. This study sought to determine if intraoperative administration of verapamil (Ver) could reduce the risk of DGF in DCD kidney transplants. Methods/UNASSIGNED:A single-center retrospective matched cohort study was performed of 93 Ver (-) kidney transplant recipients compared with 93 Ver (+) kidney transplant recipients, matched by donor age, Kidney Donor Profile Index, and DCD status. Covariates that could impact DGF risk were evaluated by univariate and multivariate logistic regression analyses. Results/UNASSIGNED:The Ver (-) and Ver (+) matched cohorts did not have any significant differences in the demographic covariates. There was no difference in DGF rate between the Ver cohorts in either the overall study population or within the DCD subgroup. There was a trend toward reduced DGF in the Ver (+) cohort for cold ischemia time (CIT) ≤24 h, but this failed to achieve statistical significance. On multivariate analysis, only CIT was found to be independently associated with DGF. Conclusions/UNASSIGNED:Intraoperative verapamil failed to reduce DGF risk in DCD kidney allografts. Limitations to this study include nonrandomization for the intraoperative administration of verapamil and the mean CIT >24 h in the study population. Only CIT was an independent prognosticator for DGF on multivariate analysis in a cohort matched for DCD status, consistent with prior studies.

INTRODUCTION/BACKGROUND:Direct acting antiviral (DAA) therapeutics have ushered in an era in which transplanting organs from donors infected with hepatitis C virus (HCV+) into recipients without (HCV-) is an increasingly common practice. Rare but potentially life-threatening events have been reported in recipients of HCV+ organs. METHODS:Since 2018 at our institution, 182 HCV- patients have received HCV+ donor organs. Here, we retrospectively reviewed cases in which recipients' family member caregivers reported sustaining needlestick exposures at home following discharge of the transplant recipient from the hospital. RESULTS:Caregiver needlestick exposures were passively reported in three cases of HCV+ into HCV- transplants (1.64% of such cases at our center). In all instances, the exposed individuals were aiding in diabetic management and the exposure occurred via lancets or insulin needles. In one case, the recipient viral load was undetectable at the time of the exposure but in the other two, recipients were viremic, putting their family members at risk to contract HCV infection. Surveillance for the exposed individuals was undertaken and no transmissions occurred. DISCUSSION/CONCLUSIONS:For centers performing HCV+ into HCV- transplants, it is important that informed consent includes discussion of potential secondary risks to family members and caregivers. Further, protocols for post-exposure surveillance and for the acquisition of DAA treatment in the event of a secondary transmission should be in place. This article is protected by copyright. All rights reserved.

Transplanting hepatitis C viremic donor organs into hepatitis C virus (HCV)-negative recipients is becoming increasingly common; however, practices for posttransplant direct-acting antiviral (DAA) treatment vary widely. Protracted insurance authorization processes for DAA therapy often lead to treatment delays.

The current kidney allocation system (KAS) preferentially allocates kidneys from blood type A2 or A2B (A/A2B) donors to blood type B candidates. We used national data to evaluate center-level performance of A2/A2B to B transplants, and organ procurement organization (OPO) reporting of type A or AB donor subtyping, in 5-year time periods prior to (2009-2014) and following (2015-2019) KAS implementation. The number of centers performing A2/A2B to B transplants increased from 17 pre-KAS to 76 post-KAS, though this still represents only a minority of centers (7.3% pre-KAS and 32.6% post-KAS). For high-performing centers, the median net increase in A2/A2B to B transplants was 19 cases (range -2-72) per center in the 5 years post-KAS. The median net increase in total B recipient transplants was 21 cases (range -17-119) per center. Despite requirements for performance of subtyping, in 2019 subtyping was reported on only 56.4% of A/AB donors. This translates into potential missed opportunities for B recipients, and even post-KAS up to 2322 A2/A2B donor kidneys may have been allocated for transplantation as A/AB. Further progress must be made both at center and OPO levels to broaden implementation of A2/A2B to B transplants for the benefit of underserved recipients.