Background/Objectives: The rising use of liver grafts from donation after circulatory death (DCD) has been enabled by advances in normothermic regional perfusion (NRP) and machine perfusion (MP) technologies. We aimed to identify predictive biomarkers in DCD grafts subjected to NRP, followed by randomization to either normothermic machine perfusion (NMP) or dual hypothermic oxygenated perfusion (D-HOPE). Methods: Among 57 DCD donors, 32 liver grafts were transplanted, and recipients were monitored for one week post-transplant. Biomarkers linked with oxidative stress, hepatic injury, mitochondrial dysfunction, inflammation, regeneration, and autophagy were measured during NRP, end-ischemic MP, and one week post-transplant. Results: Arginase-1 (ARG-1) levels were consistently higher in discarded grafts and in recipients who later developed early allograft dysfunction (EAD). Specifically, ARG-1 levels at the end of MP correlated with markers of hepatic injury. Receiver operating characteristic analysis indicated that ARG-1 at the end of MP had a good predictive accuracy for EAD (AUC = 0.713; p = 0.02). Lipid peroxidation (TBARS) elevated at the start of NRP, declined over time, with higher levels in D-HOPE than in NMP, suggesting a more oxidative environment in D-HOPE. Metabolites like flavin mononucleotide (FMN) and NADH exhibited significant disparities between perfusion types, due to differences in perfusate compositions. Inflammatory biomarkers rose during NRP and NMP but normalized post-transplantation. Regenerative markers, including osteopontin and hepatocyte growth factor, increased during NRP and NMP and normalized post-transplant. Conclusions: ARG-1 demonstrates strong potential as an early biomarker for assessing liver graft viability during perfusion, supporting timely and effective decision-making in transplantation.

Objective Immunosuppressive agents are known to interfere with T and/or B lymphocytes, which are required to mount an adequate serologic response. Therefore, we aim to investigate the antibody response to SARS-CoV-2 in liver transplant (LT) recipients after COVID-19. Design Prospective multicentre case–control study, analysing antibodies against the nucleocapsid protein, spike (S) protein of SARS-CoV-2 and their neutralising activity in LT recipients with confirmed SARS-CoV-2 infection (COVID-19-LT) compared with immunocompetent patients (COVID-19-immunocompetent) and LT recipients without COVID-19 symptoms (non-COVID-19-LT). Results Overall, 35 LT recipients were included in the COVID-19-LT cohort. 35 and 70 subjects fulfilling the matching criteria were assigned to the COVID-19-immunocompetent and non-COVID-19-LT cohorts, respectively. We showed that LT recipients, despite immunosuppression and less symptoms, mounted a detectable antinucleocapsid antibody titre in 80% of the cases, although significantly lower compared with the COVID-19-immunocompetent cohort (3.73 vs 7.36 index level, p<0.001). When analysing anti-S antibody response, no difference in positivity rate was found between the COVID-19-LT and COVID-19-immunocompetent cohorts (97.1% vs 100%, p=0.314). Functional antibody testing showed neutralising activity in 82.9% of LT recipients (vs 100% in COVID-19-immunocompetent cohort, p=0.024). Conclusions Our findings suggest that the humoral response of LT recipients is only slightly lower than expected, compared with COVID-19 immunocompetent controls. Testing for anti-S antibodies alone can lead to an overestimation of the neutralising ability in LT recipients. Altogether, routine antibody testing against separate SARS-CoV-2 antigens and functional testing show that the far majority of LT patients are capable of mounting an adequate antibody response with neutralising ability.

Introduction: Controlled (c-) and uncontrolled (u-) DCDs are two entirely different types of donors, mainly because the duration of ischemic and reperfusion injury differs between them. We hypothesized that normothermic regional perfusion (NRP) management and performance (as indicated by the dynamic changes in blood flow and lactate) might be different in uDCDs and in cDCDs. Methods: We assessed 99 DCD donors that were consecutively evaluated by the Tuscany Regional Transplant Center from 2020 to 2024 (multi-center investigation), focusing on the comparison between NRP performance and management in uDCDs (n = 44) vs. cDCDs (n = 45). Results: NRP duration was significantly higher in uDCDs compared to cDCDs (p = 0.001). During NRP, we observed no changes in lactate values in uDCDs and cDCDs, a significant increase in transaminases, and a progressive reduction in NRP blood flow rates despite the administration of more fluids. Throughout the entire NRP duration, pH values were significantly lower and glucose levels were higher in uDCDs compared to cDCDs, even though a higher dosage of bicarbonate and insulin units were administered in uDCDs. Conclusions: In our series, we documented that NRP performance and management differed in uDCDs compared to cDCDs. This phenomenon may be mainly related to the different duration of the ischemic injury between these two types of donors. During NRP, uncontrolled DCDs showed a more severe metabolic derangement, which was only partially reversable by a more aggressive treatment (higher fluid volumes, insulin and bicarbonate dosages). Our results strongly suggest that there is likely space for optimization of NRP management in DCDs. Further research should address this issue, considering the disparity between the supply of organs and increasing transplantation needs.

Ischemia–reperfusion injury (IRI) is a mechanism based on inflammatory mediators’ release and activation of effectors of damage. Studies showed a correlation between cytokine, severity of damage, and post-operative outcomes. Ex situ perfusion may work as a platform for the treatment of IRI mechanisms, such as the removal of cytokines using cytokine adsorption (CA). We assessed the safety and benefits of an integrated CA during ex situ dual-oxygenated hypothermic (D-HOPE) and normothermic perfusion (NMP). During the period of July 2021–December 2023, 84 octogenarian liver grafts, suitable for transplantation, were considered: 12 were randomized to D-HOPE or NMP with or without CA (D-HOPE + CA, D-HOPE, NMP + CA, NMP groups, n = 3 each) and compared to 72 performed using grafts preserved in static cold storage (SCS). IL-1, IL-6, IL-10, and TNF-a perfusate concentrations were evaluated together with perfusion parameters and post-operative outcomes. Perfusion procedures were unaffected by CA integration. In NMP, cytokine levels were 10–40 times higher than in healthy subjects and 20–50 times higher than D-HOPE. Cytokines were removed both in D-HOPE and NMP, but the concentration-dependent mechanisms of action of CA led to more remarkable removal in NMP. IL-10 and TNF-a concentrations were significantly lower in NMP + CA than in NMP. The application of CA was associated with significantly higher arterial flows both in D-HOPE and NMP, and reduced neutrophil infiltration in NMP. No differences in post-operative outcomes were found among groups. In conclusion, cytokine adsorption during ex situ machine perfusion of liver grafts from elderly donors is safe and feasible and is associated with modulation of inflammatory mediators and perfusion dynamics. These findings are hypothesis-generating, and larger studies are required to determine the clinical impact of this strategy.

The management of de novo kidney tumors (DKTs) after liver transplantation (LT) is challenging due to previous transplant surgery and calcineurin inhibitors (CNI)-related nephrotoxicity. Minimally invasive renal-sparing strategies like robot-assisted partial nephrectomy (RPN) are favored, but a transperitoneal approach may be limited by the previous transplant surgery and the location of the DKT; in such cases, CT-guided cryoablation may be an alternative option. In this retrospective cohort study, we aimed to compare RPN and cryoablation for the treatment of DKT in LT recipients. The primary endpoints were the efficacy (R0 resection in RPN, absence of the tumor at first follow-up for cryoablation) and the safety of the procedures (postoperative morbidity and increase in creatine level). The periprocedural costs and the oncologic efficacy (recurrence and overall survival) were the secondary endpoints. Twelve LT recipients (91.7% males, mean age 65 years) underwent RPN (n = 6) or cryoablation (n = 6) for DKT; the median interval between LT and diagnosis of DKT was 142.5 vs. 117.5 months, respectively. Efficacy was obtained in all patients after RPN and cryoablation. Postoperative morbidity was 16.7% in each group, and the postoperative increase in creatinine values was similar. Hospital stay was shorter following cryoablation vs. RPN (3.1 vs. 6.7 days; p = 0.03). The mean procedural costs were higher for RPN. There was no mortality and none of the patients had signs of recurrence after a median follow-up of 40.5 months. Both RPN and CT-guided cryoablation were safe and effective for the treatment of selected patients with DKT after LT. When applicable, cryoablation may be cost-effective and provide faster recovery.