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Sensitized renal transplant recipients with high levels of donor-specific alloantibody (DSA) commonly develop antibody-mediated rejection (AMR), which may cause acute graft loss or shorten allograft survival. We examined the efficacy of terminal complement inhibition with the humanized anti-C5 antibody, eculizumab, in the prevention AMR in renal transplant recipients with a positive crossmatch against their living donor. The incidence of biopsy-proven AMR in the first 3 months posttransplant in 26 highly sensitized recipients of living donor renal transplants who received eculizumab posttransplant was compared to a historical control group of 51 sensitized patients treated with a similar plasma exchange (PE)-based protocol without eculizumab. The incidence of AMR was 7.7% (2/26) in the eculizumab group compared to 41.2% (21/51) in the control group (p = 0.0031). Eculizumab also decreased AMR in patients who developed high levels of DSA early after transplantation that caused proximal complement activation. With eculizumab, AMR episodes were easily treated with PE reducing the need for splenectomy. On 1-year protocol biopsy, transplant glomerulopathy was found to be present in 6.7% (1/15) eculizumab-treated recipients and in 35.7% (15/42) of control patients (p = 0.044). Inhibition of terminal complement activation with eculizumab decreases the incidence of early AMR in sensitized renal transplant recipients (ClincalTrials.gov number NCT006707).

IMPORTANCE Several factors are associated with increased hepatocellular carcinoma (HCC) recurrence after liver transplantation (LT), but no reliable risk score has been established to determine the individual risk for HCC recurrence. OBJECTIVE We aimed to develop and validate a Risk Estimation of Tumor Recurrence After Transplant (RETREAT) score for patients with HCC meeting Milan criteria by imaging. DESIGN, SETTING, AND PARTICIPANTS Predictors of recurrence were tested in a development cohort of 721 patients who underwent LT between 2002 and 2012 at 3 academic transplant centers (University of California–San Francisco; Mayo Clinic, Rochester; and Mayo Clinic, Jacksonville) to create the RETREAT score. This was subsequently validated in a cohort of 341 patients also meeting Milan criteria by imaging who underwent LT at the University of Toronto transplant center using the C concordance statistic and net reclassification index. MAIN OUTCOMES AND MEASURES Characteristics associated with post-LT HCC recurrence. RESULTS A total of 1061 patients participated in the study; 77.8%(825) were men, and the median (IQR) age was 58.2 (53.3–63.9) years in the development cohort and 56.4 (51.7–61.0) years in the validation cohort (P < .001). In the development cohort of 721 patients (542 men), median α-fetoprotein (AFP) level at the time of LT was 8.3 ng/mL; 9.4% had microvascular invasion (n = 68), and 22.1% were beyond Milan criteria on explant (n = 159) owing to understaging by pretransplantation imaging. Cumulative probabilities of HCC recurrence at 1 and 5 years were 5.7% and 12.8%, respectively. On multivariable Cox proportional hazards regression, 3 variables were independently associated with HCC recurrence: microvascular invasion, AFP at time of LT, and the sum of the largest viable tumor diameter and number of viable tumors on explant. The RETREAT score was created using these 3 variables, with scores ranging from 0 to 5 or higher that were highly predictive of HCC recurrence (C statistic, 0.77). RETREAT was able to stratify 5-year post-LT recurrence risk ranging from less than 3%with a score of 0 to greater than 75% with a score of 5 or higher. The validation cohort (n = 340; 283 men) had significantly higher microvascular invasion (23.8% [n = 81], P < .001), explant beyond Milan criteria (37.3% [n = 159], P < .001), and HCC recurrence at 5 years (17.9% [n = 159], P = .03). RETREAT showed good model discrimination (C statistic, 0.82; 95%CI, 0.77–0.86) and superior recurrence risk classification compared with explant Milan criteria (net reclassification index, 0.40; P = .001) in the validation cohort. CONCLUSIONS AND RELEVANCE We have developed and validated a simple and novel prognostic score that may improve post-LT HCC surveillance strategies and help identify patients who may benefit from future adjuvant therapies.

Antibody production by normal plasma cells (PCs) against human leukocyte antigens (HLA) can be a major barrier to successful transplantation. We tested four reagents with possible activity against PCs (rituximab, polyclonal rabbit antithymocyte globulin (rATG), intravenous immunoglobulin (IVIG) and the proteasome inhibitor, bortezomib) to determine their ability to cause apoptosis of human bone marrow-derived PCs and subsequently block IgG secretion in vitro. IVIG, rituximab and rATG all failed to cause apoptosis of PCs and neither rituximab nor rATG blocked antibody production. In contrast, bortezomib treatment led to PC apoptosis and thereby blocked anti-HLA and antitetanus IgG secretion in vitro. Two patients treated with bortezomib for humoral rejection after allogeneic kidney transplantation demonstrated a transient decrease in bone marrow PCs in vivo and persistent alterations in alloantibody specificities. Total IgG levels were unchanged. We conclude that proteasome activity is important for PC longevity and its inhibition may lead to new techniques of controlling antibody production in vivo.

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Background and Aim The purpose of the present study was to determine the effects of IL-37 on liver cells and on liver inflammation induced by hepatic ischemia/reperfusion (I/R). Materials and methods Mice were subjected to I/R. Some mice received recombinant IL-37 (IL-37) at the time of reperfusion. Serum levels of alanine amino transferase, liver myeloperoxidase content were assessed. Serum and liver TNFα, MIP-2 and KC were also assessed. Hepatic reactive oxygen species (ROS) levels were assessed. For in vitro experiments, isolated hepatocytes and Kupffer cells were treated with IL-37 and inflammatory stimulants. Cytokine and chemokine production by these cells were assessed. Primary hepatocytes were induced cell injury and treated with IL-37 concurrently. Hepatocyte cytotoxicity and Bcl-2 expression were determined. Isolated neutrophils were treated with TNFα and IL-37 and neurtrophil activation and respiratory burst were assessed. Results IL-37 reduced hepatocyte injury and neutrophil accumulation in the liver after I/R. These effects were accompanied by reduced serum levels of TNFα and MIP-2 and hepatic ROS levels.IL-37 significantly reduced MIP-2 and KC productions from LPS-stimulated hepatocytes and Kupffer cells. IL-37 significantly reduced cell death and increased Bcl-2 expression in hepatocytes. IL-37 significantly suppressed TNFα induced-neutrophil activation. Conclusions IL-37 is protective against hepatic I/R injury. These effects are related to the ability of IL-37 to reduce proinflammatory cytokine and chemokine production by hepatocytes and Kupffer cells as well as having a direct protective effect on hepatocytes. In addition, IL-37 contributes to reduce liver injury through suppression of neutrophil activity.

Donation after cardiac death (DCD) liver allografts have been associated with increased morbidity from primary nonfunction, biliary complications, early allograft failure, cost, and mortality. Early allograft dysfunction (EAD) after liver transplantation has been found to be associated with inferior patient and graft survival. In a cohort of 205 consecutive liver-only transplant patients with allografts from DCD donors at a single center, the incidence of EAD was found to be 39.5%. The patient survival rates for those with no EAD and those with EAD at 1, 3, and 5 years were 97% and 89%, 79% and 79%, and 61% and 54%, respectively (P 5 0.009). Allograft survival rates for recipients with no EAD and those with EAD at 1, 3, and 5 years were 90% and 75%, 72% and 64%, and 53% and 43%, respectively (P 5 0.003). A multivariate analysis demonstrated a significant association between the development of EAD and the cold ischemia time [odds ratio (OR) 5 1.26, 95% confidence interval (CI) 5 1.01-1.56, P 5 0.037] and hepatocellular cancer as a secondary diagnosis in recipients (OR 5 2.26, 95% CI 5 1.11-4.58, P 5 0.025). There was no correlation between EAD and the development of ischemic cholangiopathy. In conclusion, EAD results in inferior patient and graft survival in recipients of DCD liver allografts. Understanding the events that cause EAD and developing preventive or early therapeutic approaches should be the focus of future investigations. Liver Transpl 20:1447-1453, 2014. V C 2014 AASLD.Received March 28, 2014; accepted August 7, 2014.The success of liver transplantation (LT) has expanded its therapeutic utility and necessitated the increased use of marginal donors to meet the growing demand. To understand the impact of these marginal organs, a clinical tool for identifying early allograft dysfunction (EAD) has been previously described by multiple groups. 1-4 A simple definition (characterized by high early aminotransferase levels, persistent cholestasis, and prolonged coagulopathy in the first week after LT) has previously been validated in a multicenter retrospective review of 297 LT recipients of liver allografts from both donation after brain death (DBD) and donation after cardiac death (DCD) donors. 5 This clinical tool has served as a marker for an increased risk of mortality, morbidity, allograft failure, and cost. 6 EAD has also become a target for therapeutic intervention to reduce morbidity and mortality in LT. [7][8][9] To date, there has been no published study delineating the incidence of and risk factors for EAD specifically in the recipients of liver allografts from DCD donors.Liver allografts from DCD donors are considered inferior because of an overall increased rate of allograft failure. [10][11][12] For this type of donor, the declaration of death is based on cardiopulmonary criteria