Prognostic Factors in Liver Transplant with Marginal Grafts - Review of the Literature.

Liver transplantation is the last life-saving solution for patients with end stage liver disease. The low number of available liver grafts and the increasing waiting time on transplant lists have led to the appearance of extended donation criteria and the marginal grafs, initially considered suboptimal. Allocation of grafts and identification of the most suitable "donor-recipient" pair is still under development. The fact is that the appearance of marginal grafts has expanded the donation lists and seems to have a prognosis at least comparable to the use of ideal grafts.

Pseudomonas aeruginosa infection correlates with high MFI donor-specific antibody development following lung transplantation with consequential graft loss and shortened CLAD-free survival.

BACKGROUND: Donor-specific antibodies (DSAs) are common following lung transplantation (LuTx), yet their role in graft damage is inconclusive. Mean fluorescent intensity (MFI) is the main read-out of DSA diagnostics; however its value is often disregarded when analyzing unwanted post-transplant outcomes such as graft loss or chronic lung allograft dysfunction (CLAD). Here we aim to evaluate an MFI stratification method in these outcomes. METHODS: A cohort of 87 LuTx recipients has been analyzed, in which a cutoff of 8000 MFI has been determined for high MFI based on clinically relevant data. Accordingly, recipients were divided into DSA-negative, DSA-low and DSA-high subgroups. Both graft survival and CLAD-free survival were evaluated. Among factors that may contribute to DSA development we analyzed Pseudomonas aeruginosa (P. aeruginosa) infection in bronchoalveolar lavage (BAL) specimens. RESULTS: High MFI DSAs contributed to clinical antibody-mediated rejection (AMR) and were associated with significantly worse graft (HR: 5.77, p < 0.0001) and CLAD-free survival (HR: 6.47, p = 0.019) compared to low or negative MFI DSA levels. Analysis of BAL specimens revealed a strong correlation between DSA status, P. aeruginosa infection and BAL neutrophilia. DSA-high status and clinical AMR were both independent prognosticators for decreased graft and CLAD-free survival in our multivariate Cox-regression models, whereas BAL neutrophilia was associated with worse graft survival. CONCLUSIONS: P. aeruginosa infection rates are elevated in recipients with a strong DSA response. Our results indicate that the simultaneous interpretation of MFI values and BAL neutrophilia is a feasible approach for risk evaluation and may help clinicians when to initiate DSA desensitization therapy, as early intervention could improve prognosis.

Characterisation of the novel HLA-C*01:273 allele, first identified in a Brazilian individual.

The novel HLA-C*01:273 allele, first described in a potential bone marrow donor from Brazil.

Organ Offer Review Cards: Improving Transparency on the Kidney Transplant Waitlist.

INTRODUCTION: The 2022 National Academy of Sciences, Engineering, and Medicine report on equity in organ transplantation highlighted limited transparency and accountability for organ offer declines and recommended prioritizing patient engagement in decisions regarding organ offers. Yet, there is no guidance on how to incorporate patients in organ offers. We elected to study the experiences of patients on the waitlist and their perception of a novel Organ Offer Review Card (OORC). METHODS: A prototype OORC was created using Donornet refusal codes. Sixty randomly selected kidney waitlist patients at a single center were asked to participate in a web-based survey focusing on current medical decision-making preferences and perceptions of the prototype OORC. RESULTS: Among the 43 patients reached, 17 (39.5%) completed the survey. Most participants (88.2%) expressed it was important to be involved in the decision-making about organ offers, with 100.0% of respondents wanting to know why an organ was declined. Regarding the prototype OORC, 94.1% thought it helped them understand the factors and priorities considered when selecting an organ, and 88.2% said it increased their belief that their team was acting in their best interest. CONCLUSION: An OORC could increase transparency and communication during the waitlist process while enhancing trust in the transplant team.

The novel HLA-C*04:01:01:182 allele identified in a candidate bone marrow donor by next-generation sequencing.

HLA-C*04:01:01:182 differs from the HLA-C*04:01:01:06 allele by one nucleotide substitution in the 5'UTR.

The novel HLA-C*14:02:01:31 allele identified in a candidate bone marrow donor by next-generation sequencing.

Characterisation of the novel HLA-C*14:02:01:31 allele in a 21-year-old Greek bone marrow donor.

Functionalized magnetic nanoparticles remove donor-specific antibodies (DSA) from patient blood in a first ex vivo proof of principle study.

The presence of donor-specific antibodies (DSA) such as antibodies directed against donor class I human leucocyte antigen (e.g., HLA-A) is a major barrier to kidney transplant success. As a proof of concept, functionalized magnetic nanoparticles have been designed to eliminate DSA from saline, blood and plasma of healthy donors and sensitized patients. Specific HLA-A1 protein was covalently bound to functionalized cobalt nanoparticles (fNP), human serum albumin (HSA) as control. fNP were added to anti-HLA class I-spiked saline, spiked volunteers' whole blood, and to whole blood and plasma of sensitized patients ex vivo. Anti-HLA-A1 antibody levels were determined with Luminex technology. Antibodies' median fluorescent intensity (MFI) was defined as the primary outcome. Furthermore, the impact of fNP treatment on blood coagulation and cellular uptake was determined. Treatment with fNP reduced MFI by 97 ± 2% and by 94 ± 4% (p < 0.001 and p = 0.001) in spiked saline and whole blood, respectively. In six known sensitized anti-HLA-A1 positive patients, a reduction of 65 ± 26% (p = 0.002) in plasma and 65 ± 33% (p = 0.012) in whole blood was achieved. No impact on coagulation was observed. A minimal number of nanoparticles was detected in peripheral mononuclear blood cells. The study demonstrates-in a first step-the feasibility of anti-HLA antibody removal using fNP. These pilot data might pave the way for a new personalized DSA removal technology in the future.

BOMS: blockchain-enabled organ matching system.

This work proposes a Blockchain-enabled Organ Matching System (BOMS) designed to manage the process of matching, storing, and sharing information. Biological factors are incorporated into matching and the cross-matching process is implemented into the smart contracts. Privacy is guaranteed by using patient-associated blockchain addresses, without transmitting or using patient personal records in the matching process. The matching algorithm implemented as a smart contract is verifiable by any party. Clinical records, process updates, and matching results are also stored on the blockchain, providing tamper-resistance of recipient's records and the recipients' waiting queue. The system also is capable of handling cases in which there is a donor without an immediate compatible recipient. The system is implemented on the Ethereum blockchain and several scenarios were tested. The performance of the proposed system is compared to other existing organ donation systems, and ours outperformed any existing organ matching system built on blockchain. BOMS is tested to ascertain its compatibility with public, private, and consortium blockchain networks, checks for security vulnerabilities and cross-matching efficiency. The implementation codes are available online.

Comparative Analysis of Ischemia-Reperfusion Injury in Heart Transplantation: A Single-Center Study Evaluating Conventional Ice-Cold Storage versus the Paragonix SherpaPak Cardiac Transport System.

BACKGROUND: Since the 2018 allocation system change in heart transplantation (HT), ischemic times have increased, which may be associated with peri-operative and post-operative complications. This study aimed to compare ischemia reperfusion injury (IRI) in hearts preserved using ice-cold storage (ICS) and the Paragonix SherpaPak TM Cardiac Transport System (CTS). METHODS: From January 2021 to June 2022, consecutive endomyocardial biopsies from 90 HT recipients were analyzed by a cardiac pathologist in a single-blinded manner: 33 ICS and 57 CTS. Endomyocardial biopsies were performed at three-time intervals post-HT, and the severity of IRI manifesting histologically as coagulative myocyte necrosis (CMN) was evaluated, along with graft rejection and graft function. RESULTS: The incidence of IRI at weeks 1, 4, and 8 post-HT were similar between the ICS and CTS groups. There was a 59.3% statistically significant reduction in CMN from week 1 to 4 with CTS, but not with ICS. By week 8, there were significant reductions in CMN in both groups. Only 1 out of 33 (3%) patients in the ICS group had an ischemic time >240 mins, compared to 10 out of 52 (19%) patients in the CTS group. During the follow-up period of 8 weeks to 12 months, there were no significant differences in rejection rates, formation of de novo donor-specific antibodies and overall survival between the groups. CONCLUSION: The CTS preservation system had similar rates of IRI and clinical outcomes compared to ICS despite longer overall ischemic times. There is significantly more recovery of IRI in the early post operative period with CTS. This study supports CTS as a viable option for preservation from remote locations, expanding the donor pool.

The health risk of social disadvantage is transplantable into a new host.

Low socioeconomic status (SES) is a risk factor for mortality and immune dysfunction across a wide range of diseases, including cancer. However, cancer is distinct in the use of allogeneic hematopoietic cell transplantation (HCT) as a treatment for hematologic malignancies to transfer healthy hematopoietic cells from one person to another. This raises the question of whether social disadvantage of an HCT cell donor, as assessed by low SES, might impact the subsequent health outcomes of the HCT recipient. To evaluate the cellular transplantability of SES-associated health risk, we analyzed the health outcomes of 2,005 HCT recipients who were transplanted for hematologic malignancy at 125 United States transplant centers and tested whether their outcomes differed as a function of their cell donor's SES (controlling for other known HCT-related risk factors). Recipients transplanted with cells from donors in the lowest quartile of SES experienced a 9.7% reduction in overall survival (P = 0.001) and 6.6% increase in treatment-related mortality within 3 y (P = 0.008) compared to those transplanted from donors in the highest SES quartile. These results are consistent with previous research linking socioeconomic disadvantage to altered immune cell function and hematopoiesis, and they reveal an unanticipated persistence of those effects after cells are transferred into a new host environment. These SES-related disparities in health outcomes underscore the need to map the biological mechanisms involved in the social determinants of health and develop interventions to block those effects and enhance the health of both HCT donors and recipients.

Ginkgetin Pretreatment Reduces Inflammatory Response in DCD Donor Liver via JAK2/STAT3 Signaling Pathway.

BACKGROUND Ginkgetin inhibits growth of tumor cells, reducing blood lipids, and improving atherosclerosis, but the protective effect of ginkgetin in donation after cardiac death (DCD) livers is still unknown. The aim of this study was to determine whether pretreatment of DCD donor livers with ginkgetin can reduce inflammatory response through the JAK2/STAT3 signaling pathway. MATERIAL AND METHODS Twenty male Sprague-Dawley rats (200-250 g) were randomly divided into 4 groups: Sham, DCD, Ginkgetin (0.6 mg/kg) pretreatment 1 h before surgery, and Ginkgetin (0.6 mg/kg) plus broussonin E (0.3 mg/kg) (JAK2/STAT3 signaling agonist) pretreatment 1 h before surgery. Rat livers were subjected to 30 min warm ischemia and 24 h cold storage to simulate the preservation process of DCD donor livers, followed by normothermic machine perfusion for 1 h to simulate liver reperfusion in vivo. Liver tissues and perfusate samples were collected for further studies. RESULTS Ginkgetin pretreatment significantly decreased the values of ALT and AST (P<0.05), and improved histological alterations according to improved Suzuki's Score (P<0.05). Ginkgetin also inhibited the protein expression levels of p-JAK2/JAK2 and p-STAT3/STAT3 (P<0.05). Furthermore, ginkgetin pretreatment inhibited levels of interleukin-1ß, interleukin-6 and tumor necrosis factor a (P<0.05) to suppress inflammatory response. In addition, broussonin E reversed the improvement of ginkgetin on DCD donor livers. CONCLUSIONS Ginkgetin can inhibit the inflammatory response through the JAK2/STAT3 signaling pathway to improve the quality of DCD donor livers.

Normothermic and hypothermic machine perfusion preservation versus static cold storage for deceased donor kidney transplantation.

BACKGROUND: Kidney transplantation is the optimal treatment for kidney failure. Donation, transport and transplant of kidney grafts leads to significant ischaemia reperfusion injury. Static cold storage (SCS), whereby the kidney is stored on ice after removal from the donor until the time of implantation, represents the simplest preservation method. However, technology is now available to perfuse or "pump" the kidney during the transport phase ("continuous") or at the recipient centre ("end-ischaemic"). This can be done at a variety of temperatures and using different perfusates. The effectiveness of these treatments manifests as improved kidney function post-transplant. OBJECTIVES: To compare machine perfusion (MP) technologies (hypothermic machine perfusion (HMP) and (sub) normothermic machine perfusion (NMP)) with each other and with standard SCS. SEARCH METHODS: We contacted the information specialist and searched the Cochrane Kidney and Transplant Register of Studies until 15 June 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: All randomised controlled trials (RCTs) and quasi-RCTs comparing machine perfusion techniques with each other or versus SCS for deceased donor kidney transplantation were eligible for inclusion. All donor types were included (donor after circulatory death (DCD) and brainstem death (DBD), standard and extended/expanded criteria donors). Both paired and unpaired studies were eligible for inclusion. DATA COLLECTION AND ANALYSIS: The results of the literature search were screened, and a standard data extraction form was used to collect data. Both of these steps were performed by two independent authors. Dichotomous outcome results were expressed as risk ratios (RR) with 95% confidence intervals (CI). Survival analyses (time-to-event) were performed with the generic inverse variance meta-analysis of hazard ratios (HR). Continuous scales of measurement were expressed as a mean difference (MD). Random effects models were used for data analysis. The primary outcome was the incidence of delayed graft function (DGF). Secondary outcomes included graft survival, incidence of primary non-function (PNF), DGF duration, economic implications, graft function, patient survival and incidence of acute rejection. Confidence in the evidence was assessed using the Grading of Recommendations Assessment, Development and Evaluation (GRADE) approach. MAIN RESULTS: Twenty-two studies (4007 participants) were included. The risk of bias was generally low across all studies and bias domains. The majority of the evidence compared non-oxygenated HMP with standard SCS (19 studies). The use of non-oxygenated HMP reduces the rate of DGF compared to SCS (16 studies, 3078 participants: RR 0.78, 95% CI 0.69 to 0.88; P < 0.0001; I2 = 31%; high certainty evidence). Subgroup analysis revealed that continuous (from donor hospital to implanting centre) HMP reduces DGF (high certainty evidence). In contrast, this benefit over SCS was not seen when non-oxygenated HMP was not performed continuously (low certainty evidence). Non-oxygenated HMP reduces DGF in both DCD and DBD settings in studies performed in the 'modern era' and when cold ischaemia times (CIT) were short. The number of perfusions required to prevent one episode of DGF was 7.69 and 12.5 in DCD and DBD grafts, respectively. Continuous non-oxygenated HMP versus SCS also improves one-year graft survival (3 studies, 1056 participants: HR 0.46, 0.29 to 0.75; P = 0.002; I2 = 0%; high certainty evidence). Assessing graft survival at maximal follow-up confirmed a benefit of continuous non-oxygenated HMP over SCS (4 studies, 1124 participants (follow-up 1 to 10 years): HR 0.55, 95% CI 0.40 to 0.77; P = 0.0005; I2 = 0%; high certainty evidence). This effect was not seen in studies where HMP was not continuous. The effect of non-oxygenated HMP on our other outcomes (PNF, incidence of acute rejection, patient survival, hospital stay, long-term graft function, duration of DGF) remains uncertain. Studies performing economic analyses suggest that HMP is either cost-saving (USA and European settings) or cost-effective (Brazil). One study investigated continuous oxygenated HMP versus non-oxygenated HMP (low risk of bias in all domains); the simple addition of oxygen during continuous HMP leads to additional benefits over non-oxygenated HMP in DCD donors (> 50 years), including further improvements in graft survival, improved one-year kidney function, and reduced acute rejection. One large, high-quality study investigated end-ischaemic oxygenated HMP versus SCS and found end-ischaemic oxygenated HMP (median machine perfusion time 4.6 hours) demonstrated no benefit compared to SCS. The impact of longer periods of end-ischaemic HMP is unknown. One study investigated NMP versus SCS (low risk of bias in all domains). One hour of end ischaemic NMP did not improve DGF compared with SCS alone. An indirect comparison revealed that continuous non-oxygenated HMP (the most studied intervention) was associated with improved graft survival compared with end-ischaemic NMP (indirect HR 0.31, 95% CI 0.11 to 0.92; P = 0.03). No studies investigated normothermic regional perfusion (NRP) or included any donors undergoing NRP. AUTHORS' CONCLUSIONS: Continuous non-oxygenated HMP is superior to SCS in deceased donor kidney transplantation, reducing DGF, improving graft survival and proving cost-effective. This is true for both DBD and DCD kidneys, both short and long CITs, and remains true in the modern era (studies performed after 2008). In DCD donors (> 50 years), the simple addition of oxygen to continuous HMP further improves graft survival, kidney function and acute rejection rate compared to non-oxygenated HMP. Timing of HMP is important, and benefits have not been demonstrated with short periods (median 4.6 hours) of end-ischaemic HMP. End-ischaemic NMP (one hour) does not confer meaningful benefits over SCS alone and is inferior to continuous HMP in an indirect comparison of graft survival. Further studies assessing NMP for viability assessment and therapeutic delivery are warranted and in progress.

Donor Kidney With Complete Duplication of Ureter: Is It Safe for Transplantation?

Renal transplantation is the best modality of treatment for patients with end-stage renal disease. Donor shortage remains a substantial problem, for which different strategies are employed, including acceptance of marginal donors and donor kidneys with anatomic variations. We performed a successful kidney transplant of a donor kidney that had complete duplication of the ureter. After transplant, the recipient had no urinary complications.

Impact of Pulsatile Machine Perfusion on Posttransplant Recovery in Asystole Donation: Organ Optimization and the Future of Renal Transplantation.

OBJECTIVES: With the increase in life expectancy and the aging of the population, chronic kidney disease has become increasingly prevalent in our environment. Kidney transplantation remains the gold standard treatment for end-stage renal disease, but the supply of renal grafts has not been able to keep pace with growing demand. Because of this rationale, organ selection criteria have been extended (expanded criteria donation), and alternative donation types, such as donation after circulatory death, have been evaluated. These approaches aim to increase the pool of potential donors, albeit with organs of potentially lower quality. Various forms of donations, including donation after circulatory death, have also undergone assessment. This approach aims to augment the pool of potential donors, notwithstanding the compromised quality of organs associated with such methods. Diverse strategies have been explored to enhance graft function, with one of the most promising being the utilization of pulsatile machine perfusion. MATERIALS AND METHODS: We conducted a retrospective analysis on 28 transplant recipients who met the inclusion criterion of sharing the same donor, wherein one organ was preserved by cold storage and the other by pulsatile machine perfusion. We performed statistical analysis on posttransplant recovery parameters throughout the patients' hospitalization, including admission and discharge phases. RESULTS: Statistically significant differences were noted in delayed graft function (P = .04), blood transfusions requirements, and Clavien-Dindo complications. Furthermore, an overall trend of improvement in discharge parameters and hospital stay was in favor of the pulsatile machine perfusion group. CONCLUSIONS: The use of pulsatile machine perfusion as a method of renal preservation results in graft optimization, leading to earlier recovery and fewer complications compared with cold storage in the context of donation after circulatory death.

Bidirectional transfer of human cytomegalovirus strains in donor and recipient seropositive lung transplant patients.

Donor and recipient human cytomegalovirus (HCMV) seropositive (D+R+) lung transplant recipients (LTRs) often harbor multiple strains of HCMV, likely due to transmitted donor (D) strains and reactivated recipient (R) strains. To date, the extent and timely occurrence of each likely source in shaping the post-transplantation (post-Tx) strain population is unknown. Here, we deciphered the D and R origin of the post-Tx HCMV strain composition in blood, bronchoalveolar lavage (BAL), and CD45+ BAL cell subsets. We investigated either D and/or R formalin-fixed paraffin-embedded blocks or fresh D lung tissue from four D+R+ LTRs obtained before transplantation. HCMV strains were characterized by short amplicon deep sequencing. In two LTRs, we show that the transplanted lung is reseeded by R strains within the first 6 months after transplantation, likely by infiltrating CD14+ CD163+/- alveolar macrophages. In three LTRs, we demonstrate both rapid D-strain dissemination and persistence in the transplanted lung for >1 year post-Tx. Broad inter-host diversity contrasts with intra-host genotype sequence stability upon transmission, during follow-up and across compartments. In D+R+ LTRs, HCMV strains of both, D and R origin can emerge first and dominate long-term in subsequent episodes of infection, indicating replication of both sources despite pre-existing immunity.

Effect of Donor Cigarette Smoking in Kidney Transplantation: Re-Evaluation of Long-Term Outcomes.

Cigarette smoking is a common risk factor associated with negative long-term outcomes in kidney transplant recipients. However, whether donor smoking decreases graft longevity or negatively impacts recipient survival after kidney transplantation remains unknown. Therefore, this study aims to investigate the long-term outcome in patients who received a kidney graft from a deceased smoking or non-smoking donor. A total of 580 patients were divided into two groups: patients who received a graft from a smoking donor (n = 276) and those who received a graft from a non-smoking donor (n = 304). Analysis of demographic factors showed that the non-smoking cohort was older, had more extended criteria donors and longer warm ischemia times. The primary composite endpoint of patient and graft survival was better in the smoking donor cohort when analyzed using Kaplan-Meier method but not when controlled for covariates in multivariate analyses. These findings do not support a previously reported negative impact of deceased donor smoking on kidney transplant recipients. Thus, the underlying results should not be interpreted in favor of a positive donor smoking history, but rather remind the transplant community that donor smoking should not be considered as a deciding factor in refusing an otherwise acceptable kidney graft.