A modified protocol with rituximab and intravenous immunoglobulin in emergent ABO-incompatible liver transplantation for acute liver failure

Insufficient pretransplant induction therapy is associated with diffuse intrahepatic cholangiopathy in ABO-incompatible living donor liver transplantation for acute liver failure

BACKGROUND

ABO-incompatible liver transplantation (ABOi LT) can now be successfully performed using standard pretransplant induction therapy. ABOi LT can achieve long-term outcomes comparable to those of blood type-compatible (ABOc) LT. The outcomes of patients with acute liver failure (ALF) undergoing urgent transplantation surgery with a limited induction period require further investigation.

METHODS

Between 2004 and 2023, adult patients who underwent living donor liver transplantation (LDLT) at Taipei Veterans General Hospital were included in this study. Patients were categorized into four groups for outcome analysis based on the chronicity of liver disease and transplant type. ALF patients who received ABOi LDLT, ALF patients who received ABOc LDLT, ESLD patients who received ABOi LDLT, and ESLD patients who received ABOc LDLT.

RESULTS

Diffuse intrahepatic cholangiopathy (DIC) was observed in four cases within the ABOi LDLT group (n = 3, 27.3% in group 1; n = 1, 2.6% in group 3; p = 0.03). In ABOi LDLT patients, rituximab was administered closer to LT in group 1 (5 [3-6] days before LDLT) than that in group 3 (15 [14-22] days before LDLT) ( p < 0.01). Univariate analysis identified ALF, a small graft-to-recipient weight ratio (GRWR), a low rituximab dose (<210 mg/m²), and postoperative rebound of isoagglutinin immunoglobulin M (IgM) antibody titers as factors associated with an increased risk of DIC. Three out of four patients with DIC eventually experienced allograft loss. Overall, ABOi LDLT showed inferior long-term outcomes for ALF (5-year patient survival: 62.3%/73.6%/74.1%/76.7% in groups 1/2/3/4, respectively, p = 0.25).

CONCLUSION

ABOi LDLT achieved outcomes comparable to those of ABOc LDLT among ESLD patients but not among ALF patients. DIC is associated with a high risk of allograft loss. However, the combination of potent immunosuppressive agents, early detection of antibody rebound, and timely initiation of salvage treatment may improve long-term outcomes in these patients.

Bile duct diffusion-weighted image hyperintensity predicts intrahepatic biliary complications after ABO-incompatible liver transplantation

OBJECTIVES

We assessed the value of the diffusion-weighted image (DWI) for predicting intrahepatic biliary complications (IHBC) after ABO-incompatible liver transplantation (ABOi-LT), potentially leading to refractory cholangitis.

MATERIALS AND METHODS

In this retrospective study at a single center, 56 patients who underwent ABOi-LT from March 2021 to January 2023 were analyzed. All received magnetic resonance cholangiopancreatography (MRCP) and DWI during the postoperative hospitalization. MRCP findings, including bile duct DWI hyperintensity, were assessed. Participants suspected of having a biliary infection or obstructive jaundice underwent endoscopic retrograde cholangiopancreatography (ERCP) or percutaneous transhepatic biliary drainage (PTBD) during the follow-up. Non-anastomotic biliary strictures on cholangiography were classified as IHBC, as either perihilar or diffuse form. DWI hyperintensity was compared between groups with and without IHBC. Logistic regression analysis was performed to identify independent risk factors for IHBC.

RESULTS

Of the 55 participants (median age 55 years, 39 males), IHBC was diagnosed in eight patients over a median follow-up of 15.9 months (range 5.6-31.1). Bile duct DWI hyperintensity was observed in 18 patients. Those with DWI hyperintensity exhibited a higher IHBC incidence (6/18, 33.3% vs. 2/36, 5.6%; p = 0.01), and more frequently developed the diffuse type IHBC (4/18, 22.2% vs. 1/36, 2.8%; p = 0.04). Regression analysis indicated that bile duct DWI hyperintensity is an independent risk factor for IHBC (odds ratio (OR) 10.1; 95% confidence interval (CI) 1.4, 71.2; p = 0.02) and its diffuse form (OR 15.3; 95% CI 1.2, 187.8; p = 0.03).

CONCLUSION

Postoperative DWI hyperintensity of bile ducts can serve as a biomarker predicting IHBC after ABOi-LT.

CLINICAL RELEVANCE STATEMENT

Postoperative diffusion-weighted image hyperintensity of the bile duct can be used as a biomarker to predict intrahepatic biliary complications and aid in identifying candidates who may benefit from additional management for antibody-mediated rejection.

KEY POINTS

Intrahepatic biliary complications following ABO-incompatible liver transplantation can cause biliary stricture and biloma formation. Bile duct hyperintensity on early postoperative diffusion-weighted imaging was associated with increased intrahepatic biliary complication risk. This marker is an additional method for identifying individuals who require intensive management to prevent complications.

Rituximab administration one week before ABO-incompatible liver transplantation due to drug-induced acute liver failure with hepatic coma: a case report

In cases of acute liver failure (ALF) with hepatic coma, early liver transplantation, including ABO-incompatible (ABOi) living donor liver transplantation (LDLT), should be considered. The ABO antibody barrier can be reduced using plasma exchange (PE) and the anti-CD20 antibody rituximab. Plasma exchange is also performed for drug-induced ALF and is effective for desensitization. Rituximab treatment usually requires 14 days. There is presently no established desensitization protocol for ABOi-LDLT for ALF. Here, we report a case of drug-induced ALF with hepatic coma, which was treated with ABOi-LDLT using PE and rituximab 8 days prior to surgery. A 33-year-old female, with a history of headaches for which she was taking analgesics daily, developed drug-induced ALF with hepatic coma. Her ABOi sister desired to become a liver donor. We initiated desensitization using rituximab (500 mg) and mycophenolate mofetil (MMF, 2000 mg/day), followed by five sessions of PE. Eight days after rituximab administration, ABOi-LDLT with splenectomy was performed. Postoperatively, the patient received local infusion via portal vein for 14 days and immunosuppression with tacrolimus, methylprednisolone, and MMF. No episode of cellular or antibody-mediated rejection (AMR) was observed. The patient was discharged uneventfully 56 days after ABOi-LDLT with no problems up to 15 months after the transplant.

Strategies for ABO Incompatible Liver Transplantation

Liver transplantation (LT) is a definitive treatment for the decompensated liver cirrhosis and fulminant liver failure. With limited availability of cadaveric liver allograft, ABO incompatible (ABOi) living donor liver transplantation (LDLT) plays an important part in further expansion of donor pool. Over the years, with the introduction of Rituximab and improving desensitisation protocol, outcomes of ABOi LDLT are on par with ABO compatible LT. However, ABOi LDLT protocol varies markedly from centre to centre. Intravenous Rituximab followed by plasmapheresis or immunoadsorption effectively reduce ABO isoagglutinins titre before transplant, thereby reducing the risk of antibody mediated rejection in the post-transplant period. Local infusion therapy and splenectomy are not used routinely at most of the centres in Rituximab era. Post-transplant immunosuppression usually consists of standard triple drug regime, and tacrolimus trough levels are targeted at higher level compared to ABO compatible LT. Introduction of newer therapies like Belatacept and Obinutuzumab hold promise to further improve outcomes and reduce the risk of antibody mediated rejection related complications. ABOi LT in emergency situations like acute liver failure and deceased donor LT is challenging due to limited time period for desensitisation protocol before transplant, and available evidence are still limited but encouraging.

The fate of donor-type ABO blood group antigen expression in liver grafts in ABO-incompatible adult living donor liver transplantation

BACKGROUND/PURPOSE

Donor-type ABO blood group antigens (dABOAgs) have been detected in ABO-incompatible adult living donor liver transplantation (ABOi ALDLT) grafts, but their fate and role in ABOi ALDLT rejection remain uncertain.

METHODS

The 0-day, <1-month, and 1-year serial liver graft biopsies from 30 ABOi ALDLT recipients were retrospectively evaluated. ABO antigen expression was quantitatively and serially measured by the mean number of positively stained vascular structures (endothelium of the capillaries, arteries, hepatic veins, and portal veins) within the portal tracts (sS).

RESULTS

The dABOAg sS counts of 0-day, <1-month, and 1-year liver graft biopsies (32.3, 20.8, and 20.6, respectively) decreased significantly (p < .001). Early rejection in the <1-month biopsy was observed in 8/30 (26.7%) recipients, four (13.3%) of whom showed antibody-mediated rejection. The sS counts tended to rebound in grafts showing early rejection, with minimal changes from the 0-day to <1-month period, but increased to pre-transplantation levels after 1 year, compared to that in grafts without early rejection (36.0, 20.4, 19.6 vs. 23.7, 21.9, 23.0, respectively; p = .040).

CONCLUSIONS

While dABOAg expression decreased after ABOi ALDLT, recipients showing early rejection showed sustained graft dABOAg expression. Therefore, dABOAg expression may be involved in the mechanism of accommodation in ABOi transplantation.

Impact of hepatitis B surface antigen positive grafts on liver transplantation in patients with benign and malignant liver disease

Hepatitis B surface antigen (HBsAg) persists after liver transplantation in almost all patients receiving HBsAg-positive grafts. Chronic hepatitis B virus (HBV) infection is one of the main causes of hepatocellular carcinoma (HCC). We aimed to investigate possible interactions between HBsAg-positive donors, HCC, HBV-related transplant indication, and long-term outcomes. This retrospective study enrolled 1176 patients from two centers between January 2015 and May 2019, of which 135 (11.5%) were HBsAg-positive and 1041 (88.5%) were HBsAg-negative donors. Cox regression models were fitted to study the association between variables and patient and graft survival. In univariate and multivariate analyses, the donor HBsAg status was not significantly associated with patient and graft survival in the entire cohort, but there was a significant interaction between HBsAg-positive donors and HCC, independent of HBV-related transplant indication. The cumulative incidence of patient and graft survival was significantly lower in the subgroup of HCC recipients receiving HBsAg-positive grafts, but no significant difference was found in recipients with benign liver disease. In a subgroup analysis of HCC recipients, HBsAg-positive donors were significantly associated with an increased risk of HCC recurrence (hazard ratio: 1.73; 95% confidence interval: 1.20-2.48; p = 0.003) and similar results were obtained after propensity score matching analysis. We showed excellent outcomes of using HBsAg-positive grafts in patients with benign liver disease, regardless of HBV-related transplant indications. However, positive grafts should be used with caution in recipients with HCC, which are associated with an increased risk of HCC recurrence.

When Push Comes to Shove! Emergency ABO-Incompatible Pediatric Living Donor Liver Transplant for Acute Wilson's Disease

ABO-incompatible living donor liver transplantation (ABOi-LDLT) is on the rise as a viable option in countries with limited access to deceased donor grafts. While reported outcomes of ABOi-LT in children are similar to ABO- Compatible liver transplant (ABOc-LT), most children beyond 1-2 years of age will need desensitization to overcome the immunological barrier of incompatible blood groups. The current standard protocol for desensitization is Rituximab that targets B lymphocytes and is given 2-3 weeks prior to LT. However, this timeline may not be feasible in children requiring emergency LT for acute liver failure (ALF) or acute-on-chronic liver failure (ACLF). In this emergency situation of ABOi-LT, a safe multipronged approach may be an acceptable alternative solution. We report a child with acute Wilson's disease with rapidly deteriorating liver function who underwent a successful ABOi-LDLT using a rapid desensitization protocol.

Excellent outcome following emergency deceased donor ABO-incompatible liver transplantation using rituximab and antigen specific immunoadsorption

BACKGROUND

The acceptance of ABO-incompatible (ABOi) liver grafts will expand the donor pool for a patient in urgent need for a liver transplantation (LT). Here we report our results with emergency ABOi DD (deceased donor) LT using rituximab and antigen specific immunoadsorption.

PATIENTS AND METHODS

2009 to 2019 we performed 20 ABOi DD LTs (adults n = 17, children n = 3) for patients in urgent need for a LT. Immunosuppression consisted of rituximab (n = 20) and basiliximab (n = 15) or anti-thymocyte globuline (n = 4), intravenous immunoglobulin (IVIG; n = 6), tacrolimus, prednisolone and mycophenolate mofetil. Fifteen patients were treated with IA (n = 14) or both IA and plasmapheresis (PP; n = 1) pre-transplant and 18 patients were treated with IA (n = 15) or both IA and PP (n = 3) post-transplant. The median pre-transplant MELD- score was 40 (range 18-40). Patient and graft survival and complications were compared to a 1:4 case matched control group of ABO-identical or compatible (ABOid/c) DDLT.

RESULTS

The 1-, 3- and 5-year patient and graft survival rates were 85, 85 and 78% for the ABOi recipients and not significantly different compared to ABOid/c controls. Only one ABOi patient developed antibody-mediated rejection.

CONCLUSION

Patient and graft survival after emergency ABOi DDLT using rituximab and immunoadorption was equal to ABOid/DDLT. ABOi DD LT was a successful approach to expand the donor pool for patients in urgent need for a liver graft.

Long-term outcomes of emergency ABO-incompatible living donor liver transplantation using a modified desensitization protocol for highly sensitized patients with acute liver failure: A case report

Although there is no established desensitization protocol for liver transplantation (LT), desensitization usually entails treatment with rituximab, plasmapheresis, splenectomy, and intravenous immunoglobulin (IVIG) infusion together with a local graft. The desensitization protocol is usually initiated 2 to 3 weeks before transplantation. Therefore, patients with acute liver failure warranting urgent LT are usually ineligible for ABO-incompatible (ABOi) LT. For these reasons, several attempts have been made to abridge the desensitization protocol and extend the indication for ABOi living donor LT (LDLT). Here we report a 40-year-old female diagnosed with chronic hepatitis B and acute-on-chronic liver failure (model for end-stage liver disease score, 31). In the absence of a suitable compatible liver donor, emergency ABOi LT was planned using a modified desensitization protocol. The preoperative isoagglutinin (IA) titer was 1 : 1,024 and the preoperative T- and B-cell cross-matches were positive. The patient received a single dose of rituximab (375 mg/m²) and IVIG (0.8 g/kg) was administered from the anhepatic phase until three days after transplantation. Although the patient developed acute cellular rejection in the early stages after LT, she has maintained a stable graft function, even after 5 years. In summary, a modified desensitization protocol consisting of rituximab and IVIG is a feasible strategy for highly sensitized patients with elevated IA titers indicated for urgent LDLT.

Clinical outcomes after ABO-incompatible liver transplantation: A systematic review and meta-analysis

BACKGROUND

ABO-incompatible liver transplantation (ABOi-LT) is increasingly used to overcome donor shortage. Evidence about disadvantage and advantage in comparison with ABO-compatible liver transplantation (ABOc-LT) needs to be performed in the early and late periods. Herein, We compared the short-term and long-term outcomes between ABOi-LT and ABOc-LT cohorts.

METHODS

We performed a meta-analysis based on the observation studies which included outcomes at ≥1 year after ABOi-LT and ABOc-LT procedures, based on the MEDLINE (via Pubmed), the Cochrance Central Register of Controlled Trials (CENTRAL), and EMBASE (via Ovid) systems. Two researchers independently screened each study according to the pre-established inclusion and exclusion criteria to assess the quality of each study and extracted data from published studies. The primary outcome indicators were all-cause mortality and graft survival at 1, 3 and 5 years after transplantation. In the meta-analysis, we based on the value of heterogeneity using a fixed-effect and a random-effect. A fixed-effect model was used if the value of I2 was less than or equal 50%; and a random-effect model was used if the value of I2 was greater than 50%.

FINDINGS

Out of 335 identified records, 29 records with 10,783 patients with liver transplants; 2137 of them were ABOi-LTs and the remaining 8646 were ABOc-LTs. There was no significant difference at 1-year, 3-year, and 5-year in all-cause mortality, death-censored graft survival and complication incidence rate between ABO-incompatible living donor liver transplantation (ABOi-LDLT) group and ABO-compatible living donor liver transplantation (ABOc-LDLT) group. Compared with ABO-compatible deceased donor liver transplantation (ABOc-DDLT), ABO-incompatible deceased donor liver transplantation (ABOi-DDLT) had a higher 1-year all-cause mortality, and the value of totally pooled odds ratio (OR) was 1.89 (1.28,2.80). However, there was no significant difference at 3-year and 5-year all-cause mortality between ABOi-DDLT and ABOc-DDLT groups. ABOi-DDLT group had a lower 1-year and 5-year death-censored graft survival than ABOc-DDLT, as the value of totally pooled OR was 1.91 (1.41,2.60) and 1.52 (1.12,2.05), respectively. No significant difference was detected at 3-year death-censored graft survival between ABOi-DDLT and ABOc-DDLT groups. ABOi-DDLT group had a higher complication incidence rate than ABOc-DDLT, and the value of totally pooled OR was 2.26 (1.53,3.33). We found no obvious bias except for the complication of living donor liver transplantation (LDLT; P = 0.038).

IN CONCLUSION

The short-term and long-term outcomes were worse after ABOi-DDLT than ABOc-DDLT in the all-cause mortality, death-censored graft survival, and complication incidence rate. However, the same outcomes were essentially comparable between ABOi-LDLT vs. ABOc-LDLT cohorts. Considering the current shortage of liver donors, we believe that ABOi-LT from living donor and deceased donors can save lives under emergency situations.

C-Reactive Protein Is an Independent Predictor of 30-Day Bacterial Infection Post-Liver Transplantation

The relationship between aseptic systemic inflammation and postoperative bacterial infection is unclear. We investigated the correlation of systemic inflammation biomarkers with 30-day clinically significant bacterial infections (CSI) after liver transplantation (LT). This retrospective study enrolled 940 patients who received LT and were followed for 30 days. The primary end point was 30-day CSI events. The cohort was divided into exploratory (n = 508) and validation (n = 432) sets according to different centers. Area under the receiver operated characteristic (AUROC) and Cox regression models were fitted to study the association between baseline systemic inflammation levels and CSI after LT. A total of 255 bacterial infectious events in 209 recipients occurred. Among systemic inflammation parameters, baseline C-reactive protein (CRP) was independently associated with 30-day CSI in the exploratory group. The combination of CRP and organ failure number showed a good discrimination for 30-day CSI (AUROC = 0.80, 95% CI, 0.76-0.84) and the results were confirmed in an external verification group. Additionally, CRP levels were correlated with bacterial product lipopolysaccharide. In conclusion, our study suggests that pre-transplantation CRP is independent of other prognostic factors for 30-day CSI post-LT, and can be integrated into tools for assessing the risk of bacterial infection post-LT or as a component of prognostic models.

ABO-incompatible living donor liver transplantation with high preoperative antibody titer: A case report

INTRODUCTION AND IMPORTANCE

ABO-incompatible living donor liver transplantation (ABOi-LDLT) is essential for expanding the donor pool. ABOi-LDLT prognosis has improved since desensitization treatment with rituximab; however, patients with high antibody titers are considered to be at high risk of antibody mediated rejection (AMR). Nevertheless, the preoperative antibody titer cutoff levels that preclude ABOi-LDLT have not yet been determined. In this study, the highest preoperative antibody titer was 1:4096, and the recipient had good outcomes. There has been only one report of good outcomes with a preoperative antibody titer of more than 1:4096. We hypothesized that high preoperative antibody titers in ABOi-LDLT may not be associated with AMR in protocols involving rituximab.

CASE PRESENTATION

The recipient was a 22-year-old man with biliary atresia and underwent ABOi-LDLT (B to O). We administered 500 mg of rituximab 14 days prior and then 300 mg of rituximab one day prior to ABOi-LDLT. The recipients preoperative IgG antibody titer was 1:4096. Postoperative immunosuppressive protocol involved steroids, tacrolimus, and mycophenolate mofetil. The patient had satisfactory graft function three years following ABOi-LDLT.

CLINICAL DISCUSSION

The antibody that is responsible for posttransplant AMR should be newly synthesized after transplantation as a result of sensitization by antigens on the vascular endothelial cells of the graft. In ABOi-LDLT, natural antibodies may not cause AMR.

CONCLUSIONS

The most important factor for preventing AMR in recipients undergoing ABOi-LDLT is the suppression of de novo antibodies. High preoperative antibody titers may not necessarily preclude ABOi-LDLT, provided that rituximab is used in desensitization.

No diffuse intrahepatic biliary stricture after ABO-incompatible adult living donor liver transplantation using tailored rituximab-based desensitization protocol

Background

Rituximab (RTx) desensitization protocol offered good outcome in ABO-incompatible (ABOi) living donor liver transplantation (LDLT). However, diffuse intrahepatic biliary stricture (DIHBS) is still inevitable hurdle. We selectively added postoperative high dose intravenous immunoglobulin (IVIG) and/or simultaneous splenectomy if ABO isoagglutinin titer just before liver transplantation after plasma exchange (PE) was higher than 1/16. Herein, we reported the excellent outcome of ABOi LDLT without DIHBS using tailored desensitization protocol and compared it with that of ABO-compatible (ABOc) LDLT.

Methods

Sixty-five cases (14.8%) of ABOi LDLTs were performed among 438 primary adult LDLTs in our center between March 2012 and June 2017. We performed 1-to-2 propensity score matching (PSM) to extract 60 cases of ABOi LDLTs and 120 cases of ABOc LDLTs.

Results

There were no significant differences in clinical characteristics between ABOi and ABOc recipients. There were no significant differences in complications and rejection. There was no DIHBS in both groups. The 1-, 3-, and 5-year overall survival rates were 98.3%, 86.7%, and 82.9% in ABOi group and 96.7%, 86.7%, and 85.4% in ABOc group, respectively (P=0.88). Most common cause of deaths of both groups was hepatocellular recurrence. The 1-, 3-, and 5-year biliary complication (anastomosis leakage or stricture) free survival rates were 81.4%, 69.5%, and 67.5% in ABOi group and 83.0%, 81.3%, and 80.0% in ABOc group, with no significant differences (P=0.11).

Conclusions

RTx-based tailored (optional IVIG + splenectomy) desensitization protocol for ABOi LDLT was feasible and acceptable.

Successful ABO-incompatible living donor liver transplantation using splenectomy and intravenous immunoglobulin in high isoagglutinin titer patients

The role of the isoagglutinin (IA) titer in liver transplantation (LT) is still not well defined, but the general belief is that a higher titer may result in a higher risk of rejection in ABO-incompatible living donor LT. To reduce the IA titer by 1:16 or lower, plasmapheresis is usually performed before transplantation. However, there is no established protocol for patients for whom plasmapheresis has failed before reaching the target IA titers. Here, we report the cases of three patients who show high baseline IA titers and have failed plasmapheresis: no-response to plasmapheresis, allergic reaction associated with plasmapheresis, and anaphylactic reaction to platelet transfusion. For various reasons, after several plasmapheresis procedures, IA titers were not effectively reduced. In these patients, splenectomy and intravenous immunoglobulin (0.8 g/kg, from the anhepatic phase to 2 days after transplantation) were carried. The protocol biopsy on postoperative day 7 showed no histologic evidence of meaningful acute rejection. The main aim of this work is to demonstrate that we can apply this protocol to patients who have high baseline IA titers and have failed plasmapheresis. Furthermore, this report is enhanced to promote to the transplant community this approach with this type of recipient.

Identification of HO-1 as a novel biomarker for graft acute cellular rejection and prognosis prediction after liver transplantation

Background

Liver transplantation (LT) is the most effective treatment for patients with end-stage liver diseases, but acute rejection is still a major concern. However, the mechanisms underlying rejection remain unclear. Biomarkers are lacking for predicting rejection and long-term survival after LT.

Methods

Isobaric tags for relative and absolute quantitation (iTRAQ)-based proteomics was performed between acute cellular rejection (ACR) and non-rejection recipients. The molecular signature differences and potential biomarkers were identified by comprehensive bioinformatics. Heme oxygenase-1 (HO-1) expression and its association with clinical outcomes were investigated by tissue microarrays consisted of liver specimens from recipients with (n=80) and without ACR (n=57).

Results

A total of 287 differentially expressed proteins (DEPs) were identified. Pathway analysis revealed that T/B cell activation, integrin/inflammation signaling pathway, etc. were significantly correlated with ACR. Through comprehensive bioinformatics, HO-1 was identified as a candidate potential biomarker for ACR. In tissue microarray (TMA) analysis, HO-1 expression was significantly higher in ACR group than in non-rejection group (P<0.01). Preoperative Child-Pugh and Meld scores were significantly higher in recipients with high HO-1 expression (P<0.01). In a mean 5-year follow-up, recipients with high HO-1 expression were associated with a shorter overall survival (P<0.05). Further multivariate analyses indicated that HO-1 could be an independent adverse prognostic factor for post-transplant survival (P=0.005).

Conclusions

A total of 287 DEPs were identified, providing a set of targets for further research. Recipients with high preoperative HO-1 expression were associated with ACR. HO-1 may be used as a potential biomarker for predicting the development of post-transplant allograft ACR and recipient's survival.

Exosome-derived galectin-9 may be a novel predictor of rejection and prognosis after liver transplantation

Acute cellular rejection (ACR) remains a major concern after liver transplantation. Predicting and monitoring acute rejection by non-invasive methods are very important for guiding the use of immunosuppressive drugs. Many studies have shown that exosomes and their contents are potential biomarkers for various liver diseases. Here, we identify and validate the role of exosomes and galectin-9 in ACR after liver transplantation. Exosomes were isolated from three sets of paired patients, with and without ACR, and the proteins within the exosomes were isolated and identified. Candidate proteins were then validated using a tissue microarray containing resected liver samples from 73 ACR and 63 non-rejection patients. Finally, protein expression and clinical manifestations were included in Kaplan-Meier survival and Cox regression analyses. Circulating exosomes were isolated from ACR and non-rejection patients and characterized using transmission electron microscopy and western blotting for CD63/CD81. Western blotting experiments revealed higher levels of galectin-9 protein in circulating exosomes from ACR recipients. Immunohistochemical analysis of the tissue microarray showed that the expression of galectin-9 in resected liver was significantly higher in the ACR group than in the non-rejection group (P<0.05). Higher levels of galectin-9 expression in resected livers were associated with poorer prognosis (P<0.05). Exosome-derived galectin-9 may be a novel predictor of rejection and prognosis after liver transplantation.

ABO-Incompatible Liver Transplantation - A Review of the Historical Background and Results

ABO-incompatible liver transplantation (ABOi LT) using conventional immunosuppression has been considered a contraindication due to the high risk for antibody-mediated complications potentially resulting in graft loss. However, organ shortage has led to the development of anti-A/B antibody reducing immunosuppressive protocols which have made the outcome after living donor (LD) ABOi LT equivalent to that achieved with LD ABO-compatible (ABOc). The experience of deceased donor (DD) ABOi LT is however still limited. In this article, we discuss the historical background and the results after ABOi LT, in the setting of both LD and DD transplantation. We also discuss the remaining hurdles and future strategies in the breaching of the ABO barrier for LT.

A simplified protocol using rituximab and immunoglobulin for ABO-incompatible low-titre living donor liver transplantation

BACKGROUND & AIMS

No consensus has been reached regarding optimal treatment strategies for ABO-incompatible (ABO-I) living donor liver transplantation (LDLT). We introduce a simplified protocol using rituximab and intravenous immunoglobulin (IVIG).

METHODS

Data were analysed on adult patients who underwent ABO-I LDLT of which protocol added rituximab (300 mg/m² ) before surgery and IVIG (0.8 g/kg) on post-operative days 1 and 4 to the conventional immunosuppressive regimen used in ABO-compatible (ABO-C) LDLT, without plasmapheresis, splenectomy or graft local infusion. The outcomes were compared with those of ABO-C LDLT by 1:2 propensity score-matched analysis.

RESULTS

Consecutive 43 ABO-I LDLT patients were identified between 2014 and 2016. Before desensitization, the median isoagglutinin titre was 1:8 (range, 1:2-1:64). The titre was reduced to 4 (range, 0-16) at the time of LDLT. None showed a rebound rise of isoagglutinin titres. No antibody-mediated rejection occurred. Biliary stricture was the most common complication with an incidence of 30.2%. A comparator group of 86 ABO-C LDLT patients were selected. There was no statistical difference in the overall complication rate including acute cellular rejection, biliary complications and infection between ABO-I and ABO-C groups. The 3-year cumulative patient survival rates in the ABO-I and ABO-C groups were 82.4% and 85.9% respectively (P = .115).

CONCLUSIONS

A simplified protocol using rituximab and IVIG for ABO-I LDLT was safe and effective in achieving sufficient desensitization and comparable outcomes in patients with the titre no higher than 1:64.

Outcomes after liver transplantation in accordance with ABO compatibility: A systematic review and meta-analysis

AIM

To evaluate the differences in outcomes between ABO-incompatible (ABO-I) liver transplantation (LT) and ABO-compatible (ABO-C) LT.

METHODS

A systematic review and meta-analysis were performed by searching eligible articles published before No-vember 28, 2016 on MEDLINE (PubMed), EMBASE, and Cochrane databases. The primary endpoints were graft survival, patient survival, and ABO-I-related complications.

RESULTS

Twenty-one retrospective observational studies with a total of 8247 patients were included in this meta-analysis. Pooled results of patient survival for ABO-I LT were comparable to those for ABO-C LT. However, ABO-I LT showed a poorer graft survival than ABO-C LT (1-year: OR = 0.66, 95%CI: 0.57-0.76, P < 0.001; 3-year: OR = 0.74, 95% CI 0.64-0.85, P < 0.001; 5-yearr: OR =0.75, 95%CI: 0.66-0.86, P < 0.001). Furthermore, ABO-I LT was associated with more incidences of antibody-mediated rejection (OR = 74.21, 95%CI: 16.32- 337.45, P < 0.001), chronic rejection (OR =2.28, 95%CI: 1.00-5.22, P = 0.05), cytomegalovirus infection (OR = 2.64, 95%CI: 1.63-4.29, P < 0.001), overall biliary complication (OR = 1.52, 95%CI: 1.01-2.28, P = 0.04), and hepatic artery complication (OR = 4.17, 95%CI: 2.26-7.67, P < 0.001) than ABO-C LT. In subgroup analyses, ABO-I LT and ABO-C LT showed a comparable graft survival in pediatric patients and those using rituximab, and ABO-I LT showed an increased acute cellular rejection in cases involving deceased donor grafts.

CONCLUSION

Although patient survival in ABO-I LT was comparable to that in ABO-C LT, ABO-I LT was inferior to ABO-C LT in graft survival and several complications. Graft survival of ABO-I LT could be comparable to that of ABO-C LT in pediatric patients and those using rituximab.

Simultaneous ABO-incompatible living-donor liver transplantation and splenectomy without plasma exchange in China: Two case reports

ABO-incompatible (ABO-i) living-donor liver transplantation (LDLT) is performed if an ABO-compatible graft cannot be obtained. However, a perfect desensitization protocol has not been established worldwide, especially for simultaneous ABO-i LDLT and splenectomy. We herein report two cases of ABO-i LDLT. To the best of our knowledge, this is the first case report of ABO-i LDLT in an adult patient in China. Splenectomy and T-cell-targeted immunosuppression (basiliximab) was used to overcome the blood group barrier in these recipients. The patients had good graft function without signs of antibody-mediated rejection throughout the 12-month follow-up. Thus, ABO-i LDLT with splenectomy is undoubtedly life-saving when an ABO-compatible graft cannot be obtained for patients in critical condition.

Retraction: "Safety limitations of fatty liver transplantation can be extended to 40%: Experience of a single centre in China", by Yu Z., Yu S., Zhang L., Feng X., Zhang M., et al

The above article, published online on 13 October 2016 in Wiley OnlineLibrary (wileyonlinelibrary.com), has been retracted by agreement between the journal Editor in Chief, Mario U. Mondelli, and John Wiley & Sons Ltd. see accompanying Editorial Note It has come to the attention of the Editors that the article may have contained data referring to the use of organs retrieved from executed prisoners and not from donors after cardiac death (DCD), thus breaching international organ donation ethical standards. Further information is contained in the accompanying Editorial link. REFERENCE Yu Z, Sun Z, Yu S, et al. Safety limitations of fatty liver transplantation can be extended to 40%: experience of a single centre in China. Liver Int. 2016; doi: 10.1111/liv.13244.

Current techniques for AB0-incompatible living donor liver transplantation

For a long time, it was considered medical malpractice to neglect the blood group system during transplantation. Because there are far more patients waiting for organs than organs available, a variety of attempts have been made to transplant AB0-incompatible (AB0i) grafts. Improvements in AB0i graft survival rates have been achieved with immunosuppression regimens and plasma treatment procedures. Nevertheless, some grafts are rejected early after AB0i living donor liver transplantation (LDLT) due to antibody mediated rejection or later biliary complications that affect the quality of life. Therefore, the AB0i LDLT is an option only for emergency situations, and it requires careful planning. This review compares the treatment possibilities and their effect on the patients’ graft outcome from 2010 to the present. We compared 11 transplant center regimens and their outcomes. The best improvement, next to plasma treatment procedures, has been reached with the prophylactic use of rituximab more than one week before AB0i LDLT. Unfortunately, no standardized treatment protocols are available. Each center treats its patients with its own scheme. Nevertheless, the transplant results are homogeneous. Due to refined treatment strategies, AB0i LDLT is a feasible option today and almost free of severe complications.

ABO-Incompatible Adult Living Donor Liver Transplantation Under the Desensitization Protocol With Rituximab

ABO incompatibility is no longer considered a contraindication for adult living donor liver transplantation (ALDLT) due to various strategies to overcome the ABO blood group barrier. We report the largest single-center experience of ABO-incompatible (ABOi) ALDLT in 235 adult patients. The desensitization protocol included a single dose of rituximab and total plasma exchange. In addition, local graft infusion therapy, cyclophosphamide, or splenectomy was used for a certain time period, but these treatments were eventually discontinued due to adverse events. There were three cases (1.3%) of in-hospital mortality. The cumulative 3-year graft and patient survival rates were 89.2% and 92.3%, respectively, and were comparable to those of the ABO-compatible group (n = 1301). Despite promising survival outcomes, 17 patients (7.2%) experienced antibody-mediated rejection that manifested as diffuse intrahepatic biliary stricture; six cases required retransplantation, and three patients died. ABOi ALDLT is a feasible method for expanding a living liver donor pool, but the efficacy of the desensitization protocol in targeting B cell immunity should be optimized.

Case-matched comparison of ABO-incompatible and ABO-compatible living donor liver transplantation

BACKGROUND

ABO-incompatible (ABO-I) living donor liver transplantation (LDLT) has a high success rate. There are few detailed comparisons regarding biliary complications, infective complications and patient survival between ABO-compatible (ABO-C) and ABO-I LDLT. The aim was to compare the outcomes of ABO-I LDLT with those of ABO-C LDLT using the matched-pairs method.

METHODS

Patients who underwent ABO-I LDLT procedures between 2010 and 2013 were studied. They were matched for significant variables with patients who had ABO-C LDLT (1:2 matching).

RESULTS

Forty-seven ABO-I LDLT procedures were included. Ninety-four patients who had ABO-C LDLT were selected as a comparator group. The incidence of cytomegalovirus, bacterial and fungal infections during the first 3 months was similar after ABO-I LDLT and ABO-C LDLT (85 versus 76 per cent, 28 versus 37 per cent, and 13 versus 20 per cent, respectively). Antibody-mediated rejection occurred after two procedures within 2 weeks of transplantation, but liver function improved with plasma exchange in both patients. There were no differences in the rate of acute rejection and biliary complications between ABO-I and ABO-C groups (P = 0.478 and P = 0.511 respectively). Three patients who had ABO-I LDLT developed diffuse intrahepatic biliary complications and progressed to graft failure. The 1-, 2- and 3-year patient survival rates after ABO-I LDLT and ABO-C LDLT were 89 versus 87 per cent, 85 versus 83 per cent, and 85 versus 79 per cent, respectively.

CONCLUSION

The short-term outcomes of ABO-I LDLT were comparable to those of ABO-C LDLT in this study. ABO-I LDLT is an effective and safe transplant option with the potential to expand the pool of live donors.