Recipient interleukin-28B Rs12979860 C/T polymorphism and acute cellular rejection after liver transplantation: role of the calcineurin inhibitor used

Importance of genetic polymorphisms in liver transplantation outcomes

Although, liver transplantation serves as the only curative treatment for patients with end-stage liver diseases, it is burdened with complications, which affect survival rates. In addition to clinical risk factors, contribution of recipient and donor genetic prognostic markers has been extensively studied in order to reduce the burden and improve the outcomes. Determination of single nucleotide polymorphisms (SNPs) is one of the most important tools in development of personalized transplant approach. To provide a better insight in recent developments, we review the studies published in the last three years that investigated an association of recipient or donor SNPs with most common issues in liver transplantation: Acute cellular rejection, development of new-onset diabetes mellitus and non-alcoholic fatty liver disease, hepatocellular carcinoma recurrence, and tacrolimus concentration variability. Reviewed studies confirmed previously established SNP prognostic factors, such as PNPLA3 rs738409 for non-alcoholic fatty liver disease development, or the role of CYP3A5 rs776746 in tacrolimus concentration variability. They also identified several novel SNPs, with a reasonably strong association, which have the potential to become useful predictors of post-transplant complications. However, as the studies were typically conducted in one center on relatively low-to-moderate number of patients, verification of the results in other centers is warranted to resolve these limitations. Furthermore, of 29 reviewed studies, 28 used gene candidate approach and only one implemented a genome wide association approach. Genome wide association multicentric studies are needed to facilitate the development of personalized transplant medicine.

A risk assessment model of acute liver allograft rejection by genetic polymorphism of CD276

Background

Liver transplantation is an effective therapy for end‐stage liver diseases and acute liver failure. After the operation, however, recipients may suffer grafts loss induced by alloimmune reaction, which is termed as acute allograft rejection. The interaction between costimulatory molecules, CD276, and its ligand, TREML2, promotes T cell‐mediated immune response, as well as acute or chronic allograft rejection. Our research aimed at correlating genetic polymorphisms of CD276/TREML2 with acute rejection, and evaluating its prognostic value of acute rejection after liver transplantation.

Methods

The study enrolled a total of 388 recipients. Among them, acute allograft rejection was observed in 54 cases. We performed single nucleotide polymorphism genotyping of CD276, including rs11072431, rs11574495, rs12593558, rs12594627, rs2127015, rs3816661 and rs7176654, and TREML2, including rs4714431, rs6915083, rs7754593, and rs9394767 from preoperative peripheral blood genome DNA.

Results

We found rs2127015 of CD276, rs6915083 and rs7754593 of TREML2, and HBV infection as well were associated with acute rejection. And, rs2127015 influences CD276 expression. Moreover, we established a risk assessment model, composited by statistically proved risk factors.

Conclusion

By integrating both clinical and genetic variables, liver transplant recipients can be categorized into different risk groups, and might benefit from individualized therapies.

The impact of the recipient and donor interferon lambda-3 polymorphism on the course of HCV infection following liver transplantation

Aim of the study

Aim of the study was to assess the impact of the recipient and donor interferon lambda-3 (IFNL3) single-nucleotide polymorphisms (SNPs) rs12979860 and rs8099917 on the course of hepatitis C virus (HCV) reinfection following liver transplantation.

Material and methods

The study involved 141 subjects after liver transplantation for HCV-induced cirrhosis, performed between 2000 and 2015. It assessed the impact of both SNPs on the outcomes of interferon/ribavirin (IFN/RBV) treatment following transplantation, HCV viral load, laboratory test results, histological lesions in the liver graft, the risk of acute rejection, and the development of hepatocellular carcinoma (HCC) in patient’s own liver.

Results

In the case of rs12979860, SVR was achieved in 58.8% of recipients with the CC genotype, and only 12% of recipients with the TT genotype (p = 0.016). Recipients with the rs12979860 CC variant had lower viral load and lower alanine transaminase (ALT) activity than recipients with a non-CC variant. Opposite effects were demonstrated in the analysis of the donors’ genotype. Recipients with the unfavorable variants (rs12979860 TT and rs8099917 GG) had a lower risk of graft rejection and tended to have a higher risk of developing HCC in their own liver.

Conclusions

The IFNL3 rs12979860 polymorphism may be considered a predictor for IFN/RBV effectiveness following liver transplantation. The course of HCV reinfection following liver transplantation may be more aggressive if an unfavorable variant in the recipient coexists with a promising variant in the donor. Particularly careful monitoring for HCC in recipients with unfavorable IFNL3 variants is warranted.

Biliary strictures after liver transplantation: role of interleukin 28B genotypes in cyclosporine treated

INTRODUCTION

The role of Interleukin 28B (IL-28B) genetic polymorphisms in influencing the occurrence of biliary complications after liver transplantation has never been evaluated. This study aimed to investigate whether IL-28B rs12979860C/T polymorphisms associate with the occurrence of biliary complications after liver transplantation and if these complications may influence survival.

METHODS

One hundred seventy one recipients (133 males) who underwent liver transplantation were recruited. To confirm the mechanical etiology of cholestasis, endoscopic cholangio pancreatography, percutaneous and/or trans-Kehr cholangiography or cholangio magnetic resonance were performed. Two main clinical pictures were identified: biliary strictures and biliary leakage. Immunosuppressive therapy was based on cyclosporine (N = 54) or tacrolimus (N = 117), in association with steroids during the first month after operation. IL-28B rs12979860C/T genotypes were detected by means of polymerase chain reaction.

RESULTS

Forty patients (23.4%) presented anastomotic strictures, 7 (4.1%) non-anastomotic strictures, 10 (5.8%) leakage, 8 (4.7%) leakage plus anastomotic strictures. IL-28B rs12979860C/C genotype in association with cyclosporin was found to be an independent predictor of anastomotic strictures occurrence (p = 0.008). A significant difference in 5 years survival was observed between patients with viral etiology of liver disease experiencing either anastomotic or non-anastomotic strictures (16/23) and the remaining patients (104/112, p = 0.001).

CONCLUSIONS

In recipients carrying rs12979860 IL-28B C/C genotype the use of cyclosporine seems to contribute to enhance the probability of developing biliary complications which in hepatitis B and C positives appear to reduce patient survival. If confirmed in larger studies the use of cyclosporine in these patients could be revised.

Post-liver transplant hepatitis C virus recurrence: an unresolved thorny problem

Hepatitis C virus (HCV)-related cirrhosis represents the leading cause of liver transplantation in developed, Western and Eastern countries. Unfortunately, liver transplantation does not cure recipient HCV infection: reinfection universally occurs and disease progression is faster after liver transplant. In this review we focus on what happens throughout the peri-transplant phase and in the first 6-12 mo after transplantation: during this crucial period a completely new balance between HCV, liver graft, the recipient's immune response and anti-rejection therapy is achieved that will deeply affect subsequent outcomes. Nearly all patients show an early graft reinfection, with HCV viremia reaching and exceeding pre-transplant levels; in this setting, histological assessment is essential to differentiate recurrent hepatitis C from acute or chronic rejection; however, differentiating the two patterns remains difficult. The host immune response (mainly cellular mediated) appears to be crucial both in the control of HCV infection and in the genesis of rejection, and it is also strongly influenced by immunosuppressive treatment. At present no clear immunosuppressive strategy could be strongly recommended in HCV-positive recipients to prevent HCV recurrence, even immunotherapy appears to be ineffective. Nonetheless it seems reasonable that episodes of rejection and over-immunosuppression are more likely to enhance the risk of HCV recurrence through immunological mechanisms. Both complete prevention of rejection and optimization of immunosuppression should represent the main goals towards reducing the rate of graft HCV reinfection. In conclusion, post-transplant HCV recurrence remains an unresolved, thorny problem because many factors remain obscure and need to be better determined.

Challenges of recurrent hepatitis C in the liver transplant patient

Cirrhosis secondary to hepatitis C virus (HCV) is a very common indication for liver transplant. Unfortunately recurrence of HCV is almost universal in patients who are viremic at the time of transplant. The progression of fibrosis has been shown to be more rapid in the post-transplant patients than in the transplant naïve, hence treatment of recurrent HCV needs to be considered for all patients with documented recurrent HCV. Management of recurrent HCV is a challenging situation both for patients and physicians due to multiple reasons as discussed in this review. The standard HCV treatment with pegylated interferon and Ribavarin can be considered in these patients but it leads to a lower rate of sustained virologic clearance than in the non-transplanted population. Some of the main challenges associated with treating recurrent HCV in post-transplant patients include the presence of cytopenias; need to monitor drug-drug interactions and the increased incidence of renal compromise. In spite of these obstacles all patients with recurrent HCV should be considered for treatment since it is associated with improvement in survival and a delay in fibrosis progression. With the arrival of direct acting antiviral drugs there is renewed hope for better outcomes in the treatment of post-transplant HCV recurrence. This review evaluates current literature on this topic and identifies challenges associated with the management of post-transplant HCV recurrence.

Hepatitis C recurrence: the Achilles heel of liver transplantation

Hepatitis C virus (HCV) infection is the most common indication for liver transplantation worldwide; however, recurrence post transplant is almost universal and follows an accelerated course. Around 30% of patients develop aggressive HCV recurrence, leading to rapid fibrosis progression (RFP) and culminating in liver failure and either death or retransplantation. Despite many advances in our knowledge of clinical risks for HCV RFP, we are still unable to accurately predict those most at risk of adverse outcomes, and no clear consensus exists on the best approach to management. This review presents a critical overview of clinical factors shown to influence the course of HCV recurrence post transplant, with particular focus on recent data identifying the important role of metabolic factors, such as insulin resistance, in HCV recurrence. Emerging data for genetic markers of HCV recurrence and their usefulness for predicting adverse outcomes will also be explored.

Intravenous interferon administered during liver transplantation is not effective in preventing hepatitis C reinfection

BACKGROUND

Post-transplant hepatitis C is a major challenge after liver transplantation (LT). Antiviral therapy is associated with lower efficacy in the post-transplant setting.

AIMS

The purpose of this study was to determine the safety and effect of intravenous interferon (IFN) during the anhepatic phase of LT on hepatitis C viral load.

METHODS

Fifteen consecutive subjects undergoing liver transplant for hepatitis C cirrhosis were enrolled in the study, ten of which received study drug and five subjects served as controls. Cases received weight-based ribavirin and subcutaneous IFN at time of incision followed by intravenous IFN at the start of the anhepatic phase. Adverse events and viral levels were recorded. Repeated measures ANOVA was employed to test for differences over time, between the groups, and time by group interaction.

RESULTS

All subjects had genotype 1 virus. Hepatitis C viral load was lower at week 4 in cases compared to controls (769,004 ± 924,082 IU/ml and 2,329,896 ± 3,731,749 IU/ml, respectively), but did not reach statistical significance (p = 0.50). Three subjects developed adverse events related to IFN including pulmonary edema, rejection, and neutropenia.

CONCLUSIONS

Intravenous IFN administered during the anhepatic phase of liver transplant did not prevent graft reinfection and was associated with manageable adverse events. This regimen could be further studied if direct acting antiviral agents alone are insufficient for treating post-transplant hepatitis C.

Interleukin-28B polymorphism in hepatitis C and liver transplantation

The discovery of interleukin-28B (IL-28B) single-nucleotide polymorphisms has opened an important new area of research in liver transplantation (LT) for hepatitis C virus (HCV). Both recipient- and donor-derived IL-28B genotypes affect the post-LT treatment response, with sustained virological response (SVR) rates oscillating from >50% in homozygotes for the favorable allele (up to 90% when this is present in both the recipient and the donor) to <15% in homozygotes for the unfavorable allele and from 30% to 50% in heterozygotes. Other key posttransplant outcomes affected by the IL-28B genotype are the time to histological recurrence, HCV RNA and alanine aminotransferase levels, histological variables (including the rate of fibrosis progression), and hepatocellular carcinoma. Interactions between donor and recipient IL-28B genotypes are complex and may affect outcomes not directly related to HCV infections, such as acute cellular rejection (ACR) and metabolic diseases. A preferential allocation system in which livers from donors homozygous for the favorable allele are given to HCV patients might be postulated to improve SVR rates and post-LT outcomes in recipients with HCV infections (a 25% increase in SVR and an 8% decrease in mortality at 5 years). Although negative effects from this are difficult to predict, they could include an accelerated progression of fibrosis in patients with failed HCV eradication and an increase in ACR in non-HCV patients. Our knowledge of the precise role of IL-28B genotypes in the course of post-LT HCV is evolving, but existing knowledge suggests the possibility of exploring strategies that use IL-28B genotyping to reduce the impact of post-LT adverse outcomes.