Transforming Growth Factor-β1-Gene Polymorphism in the Development of Kidney Disease After Liver Transplantation

Mesenchymal stem cells prolong the survival of orthotopic liver transplants by regulating the expression of TGF-β1

BACKGROUND/AIMS

Recent studies have shown that transforming growth factor-β1 (TGF-β1) is prominently associated with acute rejection. This study aimed to explore the role of mesenchymal stem cells (MSCs) in the maintenance of the long-term survival of orthotopic liver transplants (OLTs) via the regulation of TGF-β1 in an experimental rat model.

MATERIALS AND METHODS

We used Lewis rats as donors and ACI rats as recipients. Hematoxylin and eosin staining was performed to evaluate histomorphological changes, and Western blot was performed to measure protein expression.

RESULTS

The expression of TGF-β1 in the liver allografts and spleen and protein levels of forkhead box P3 (FoxP3), interleukin-10 (IL-10), and cytotoxic T lymphocyte-associated antigen-4 (CTLA-4) were measured using Western blot. The suppressive capacity of CD4+CD25+ regulatory T cells was evaluated using the MTT assay. Cell-mediated immunotoxicity was evaluated using the mixed lymphocyte reaction of CD4+ T cells and cytotoxic T lymphocyte (CTL) assay of CD8+ T cells. The results showed that MSCs prolonged the survival of the OLT mice by regulating the expression of TGF-β1 at different time points. The administration of MSCs promoted a prolonged survival in the ACI recipients (105±6.6 d) compared with the MSC-untreated recipients (16.2±4.0 d). On the postoperative day (POD) 7, the MSC-treated recipients showed a significantly higher expression of TGF-β1, FoxP3, IL-10, and CTLA-4 than the MSC-untreated recipients. However, on POD 100, the MSC-treated recipients showed a lower expression of TGF-β1 and FOxP3 than that on POD 7. Moreover, on POD 7, CD4+CD25+ regulatory T cells extracted from the MSC-treated recipients showed a higher expression of FoxP3, IL-10, CTLA-4, and suppressive capacity. On POD 7, CD4+ T cells from the MSC-treated recipients showed more significantly diminished proliferative functions than the MSC-untreated recipients; further, a reduced allospecific CTL activity of CD8+ T cells was observed in the MSC-treated recipients.

CONCLUSION

MSCs may represent a promising cell therapeutic approach for inducing immunosuppression or transplant tolerance.

IL-28B rs12979860 polymorphism affect the course of chronic hepatitis and the development of HCC in Egyptian patients with hepatitis C type 4

BACKGROUND

A single nucleotide polymorphism (SNP) in the interleukin 28B (IL28B) gene may alter the trajectory of hepatitis C virus (HCV) chronic infection. Several studies have sought to determine a link between IL28B rs12979860 SNP and the development of HCV-related hepatocellular carcinoma (HCC), but with variable results, and consensus is awaited. We hypothesised that IL28B rs12979860 SNP is linked to HCC in patients with HCV type 4.

METHODS

IL28B genotyping of 300 patients with HCV-related fibrosis (n = 100), cirrhosis (n = 100) and HCC (n = 100) was carried out and the results were analysed to determine the association between the IL28B genotype and clinical outcome.

RESULTS

In IL28B TT genotype carriers, the proportions of moderate/severe fibrosis, advanced cirrhosis (Child B-C) and HCC (50%, 84% and 60.2%, respectively) were higher (p < 0.05) than in CC/CT (4.3%, 46% and 23%, respectively). IL-28B SNP was linked significantly (p < 0.05) with cirrhosis progression and HCC advanced stages. Moreover, HCC advanced Child, Okuda and CLIP stages were associated with T allele carriage (73.9%, 82.6% and 78.3% vs. 44.2%, 50.6% and 46.8% in CC/CT). The percentage of large tumour size (> 3cm) increased (p = 0.028) in TT genotype carriers (81.8% vs.52.6% in CC/CT).

CONCLUSION

IL-28B rs12979860 TT genotype is more prevalent in patients with advanced fibrosis, cirrhosis and HCC stages. Thus, it seems to be associated with poor outcomes in chronic HCV patients and to augment the risk of developing HCC.

Polymorphisms in the 3'-UTR of SCD5 gene are associated with hepatocellular carcinoma in Korean population

The purpose of the study was to assess the relationship between polymorphisms of the SCD5 and MMP1 gene and hepatocellular carcinoma (HCC). The gene polymorphisms with a minor allele frequency (MAF) > 0.05 were selected eight SNPs (rs6840, rs1065403, rs3821974, and rs3733230 in 3'-UTR; rs4693472, rs3733227, rs1848067, and rs6535374 in intron region) of SCD5 gene and two SNPs (rs1799750 and rs1144393 in promoter region) of MMP1 gene. The genotype of SCD5 and MMP1 gene SNPs were determined by direct sequencing and pyrosequencing, respectively. One hundred sixty-two patients with HCC and two hundred twenty-five control subjects were recruited in Korean male population. In terms of genotype frequencies, SCD5 genotype TC, GA, AG, and CG of rs6840, rs1065403, rs3821974, and rs3733230, respectively were higher in control group than HCC. In addition, these genotype decreased the risk (rs6840; OR 0.55, 95% CI 0.31-0.99; rs1065403; OR 0.46, 95% CI 0.26-0.83; rs3821974; OR 0.56, 95% CI 0.31-0.99; rs3733230; OR 0.62, 95% CI 0.34-1.12) of HCC, which may work as a prevention of HCC. At least one minor allele carrier of SCD5 gene polymorphisms were related to decreased risk of HCC for AFP cut-point levels > 200 or > 400 ng/ml, respectively. Our results indicate that polymorphisms in the 3'-UTR of the SCD5 gene may associated with HCC in the Korean male population.

The association between interleukin-28B gene polymorphisms as a potential biomarker and the risk of chronic Periodontitis in an Iranian population

BACKGROUND

Chronic Periodontitis (CP) is a common inflammatory disease affects supporting tissues of the teeth and can lead to tooth loss. The objective of this study was to determine the relationship between polymorphisms in the IL-28B gene and chronic periodontitis in an Iranian population.

METHODS

Two hundred and ten CP patients and one hundred healthy subjects were enrolled in the present case-control study. The rs12979860 and rs8099917 SNPs were identified using RFLP and T-ARMS-PCR methods respectively.

RESULTS

SNP analysis revealed that the G allele of rs8099917 SNP and T allele of rs12979860 SNP increased susceptibility to CP compared to the A allele and C allele (p < 0.0001, OR = 2.712, CI = 1.783-4.126; p < 0.0001, OR = 2.538, CI = 1.784-3.613 respectively). In addition, the CT/GT, TT/GG and TT/GT haplotypes were predominant in CP patients and significantly associated with the increased risk of CP.

CONCLUSION

IL-28B polymorphisms may be useful predictive factors for chronic periodontitis and correlated to the susceptibility to CP infection in our population.

Interleukin-28B TT genotype is frequently found in patients with hepatitis C virus cirrhosis but does not influence hepatocarcinogenesis

Persistent hepatitis C virus (HCV) infection is associated with progressive hepatic fibrosis and ultimately hepatocellular carcinoma. The interleukin-28B (IL28B) rs12979860 polymorphism is associated with fibrosis progression in chronic HCV infection. IL28B encodes interferon-λ, which has both antiviral and anti-proliferative properties. This study aimed to determine whether IL28B rs12979860 polymorphism is also associated with development of hepatocellular carcinoma both in chronic HCV infection and in non-viral-related cirrhosis. Real-time polymerase chain reaction and melting curve analyses were used to genotype 311 patients who underwent liver transplantation for HCV cirrhosis (n = 202) or alcoholic cirrhosis (n = 109). HCV patients were older (p = 0.012) and less likely males (p < 0.001) than patients with alcoholic cirrhosis. IL28B rs12979860 TT genotype [OR 6.08, 95 % CI 2.11-17.53; p < 0.001] and T allele carriage (CT + TT; OR 2.3, CI 95 % 1.42-3.72; p = 0.001) were more frequent among HCV patients and, among them, more common in patients infected with HCV genotype 1 (CT + TT; OR 1.79, CI 95 % 1.03-3.09; p = 0.009). Incidence of hepatocellular carcinoma was higher in HCV cirrhosis (OR 2.7, CI 95 % 1.5-4.7; p < 0.001), with no differences according to HCV genotype. IL28B genotype distribution was similar among patients with or without hepatocellular carcinoma, in both HCV patients regardless viral genotype (p = 0.84) and alcoholic patients (p = 0.91). Multivariate analysis showed that older age (OR 1.06, CI 95 % 1.02-1.1; p = 0.003) and male gender (OR 2.49, CI 95 % 1.24-5; p = 0.01) were independent risk factors for hepatocellular carcinoma in HCV patients. In summary, the current study did not find a significant association between IL28B rs12979860 polymorphism and hepatocarcinogenesis.

Protecting the Kidney in Liver Transplant Candidates: Practice-Based Recommendations From the American Society of Transplantation Liver and Intestine Community of Practice

Acute kidney injury (AKI) and chronic kidney disease (CKD) are common in patients awaiting liver transplantation, and both have a marked impact on the perioperative and long-term morbidity and mortality of liver transplant recipients. Consequently, we reviewed the epidemiology of AKI and CKD in patients with end-stage liver disease, highlighted strategies to prevent and manage AKI, evaluated the changing liver transplant waiting list's impact on kidney function, delineated important considerations in simultaneous liver-kidney transplant selection, and projected possible future transplant policy changes and outcomes. This review was assembled by experts in the field and endorsed by the American Society of Transplantation Liver and Intestinal Community of Practice and Board of Directors and provides practice-based recommendations for preservation of kidney function in patients with end-stage liver disease.

Polymorphisms near the IFNL3 Gene Associated with HCV RNA Spontaneous Clearance and Hepatocellular Carcinoma Risk

The aims of this study were to investigate associations between single nucleotide polymorphisms (SNPs) near the genes IFNL2, IFNL3, and IFNL4 and spontaneous clearance of hepatitis C virus (HCV) and to evaluate variants for their risk of hepatocellular carcinoma (HCC) among subjects in whom spontaneous HCV RNA clearance did not occur. In the first study, 889 untreated anti-HCV-seropositive patients without HCC symptoms were followed from 1991 to 2005. The spontaneous HCV clearance rate was found to be 33.1%. The TT variant of rs8099917 near IFNL3 was associated with increased spontaneous HCV RNA clearance, with an adjusted odds ratio (95% CI) of 2.78 (1.43-5.39), as was the newly-identified TT/TT dinucleotide variant rs368234815 near IFNL4 (adjusted odds ratio 2.68, 95% CI: 1.42-5.05). In the second study, associations between SNPs and HCC risk were examined in 483 HCC cases with detectable HCV RNA and 516 controls. In participants with HCV genotype 1, unfavorable genotypes for HCV clearance near IFNL3 were associated with increased HCC risk, the adjusted odds ratio (95% CI) for rs12979860 and rs8099917 being 1.73 (1.00-2.99) and 1.84 (1.02-3.33), respectively. Host characteristics should be considered to identify high-risk patients to prioritize the use of new antiviral agents and intensive screening.

Recurrent HCV after liver transplantation-mechanisms, assessment and therapy

Chronic HCV infection is the leading indication for liver transplantation. However, as a result of HCV recurrence, patient and graft survival after liver transplantation are inferior compared with other indications for transplantation. HCV recurrence after liver transplantation is associated with considerable mortality and morbidity. The development of HCV-related fibrosis is accelerated after liver transplantation, which is influenced by a combination of factors related to the virus, donor, recipient, surgery and immunosuppression. Successful antiviral therapy is the only treatment that can attenuate fibrosis. The advent of direct-acting antiviral agents (DAAs) has changed the therapeutic landscape for the treatment of patients with HCV. DAAs have improved tolerability, and can potentially be used without PEG-IFN for a shorter time than previous therapies, which should result in better outcomes. In this Review, we describe the important risk factors that influence HCV recurrence after liver transplantation, highlighting the mechanisms of fibrosis and the integral role of hepatic stellate cells. Indirect and direct assessment of fibrosis, in addition to new antiviral therapies, are also discussed.

TT genotype of transforming growth factor beta1 +869C/T is associated with the development of chronic kidney disease after liver transplantation

BACKGROUND

Chronic kidney disease (CKD) is a frequent complication in patients with liver transplantation (LT), and calcineurin inhibitor chronic nephrotoxicity, mediated by transforming growth factor beta1 (TGF-β1) is an important contributing factor. The aim of this study was to assess the influence of genetic polymorphisms of TGF-β1 in the development of CKD at 6 months after transplantation.

METHODS

One hundred sixty-four LT patients (63.4% male; overall mean age, 48.7 ± 11.6 years) were included in the analysis. CKD was considered at the 6th month after LT and was defined as an estimated glomerular filtration rate (eGFR) of <60 mL/min/1.73 m(2) as calculated on the basis of Modification of Diet in Renal Disease 4-variable equation. TGF-β1 +869 C/T and +915 G/C polymorphisms were analyzed with the use of hybridization with fluorescent probes and analysis by means of flow cytometry with the Luminex system. The association between the presence of CKD at 6 months and these polymorphisms, as well as with other known risk factors for CKD after LT, was considered.

RESULTS

In the univariate analysis, the TT genotype of TGF-β1 +869 (P = .036; odds ratio, 2.1; 95% confidence interval, 1.1-4.2), age at LT (P < .001), pre-transplantation serum creatinine levels (P = .03), eGFR (P < .001), CKD (P = .027), and immunosuppression with cyclosporine (P = .017) were associated with CKD at 6 months after transplantation. In the multivariate analysis, TGF-β1 +869TT genotype (P = .017), immunosuppression with cyclosporine (P = .002), age at LT (P = .024), and pre-transplantation CKD (P < .001) remained as independent variables associated with the development of CKD at 6 months after transplantation.

CONCLUSIONS

The genetic polymorphism TGF-β1 +869 C/T may be an independent risk factor for CKD after liver transplantation.

Genetic variation near interleukin 28B and the risk of hepatocellular carcinoma in patients with chronic hepatitis C

BACKGROUND

We aimed to clarify the association between single nucleotide polymorphism (SNP) located near interleukin 28B and hepatocellular carcinoma (HCC).

METHODS

A cohort comprising 792 patients treated with interferon for chronic hepatitis C was investigated. SNPs at rs8099917 and rs12979860 were determined. Cumulative incidence and HCC risk were analyzed by Kaplan-Meier and Cox proportional hazard analyses for a mean follow-up period of 4.9 years. Fibrosis progression rate (FPR) was determined in these patients with a known time of infection (n = 294).

RESULTS

Cumulative HCC incidence was significantly higher in rs8099917 nonTT (minor homozygote or heterozygote) patients than in rs8099917 TT (major homozygote) patients (20.8 vs. 10.5% over 10 years, logrank test, p = 0.002). This difference was notable in patients infected with genotype 1 and those treated with pegylated interferon and ribavirin. Among nonSVRs, interferon had a limited effect in suppressing alanine aminotransferase (ALT) and/or α-fetoprotein (AFP) levels in nonTT patients. The suppression of these values after interferon therapy was associated with a lower incidence of HCC. FPR were similar in TT and nonTT patients.

CONCLUSIONS

rs8099917 nonTT is related to higher HCC development in patients with HCV genotype 1 and those treated with pegylated interferon and ribavirin. Higher HCC incidence observed in nonTT patients partly results from the limited suppression of ALT and/or AFP by interferon in these patients.

Clinical Pharmacogenetics Implementation Consortium (CPIC) guidelines for IFNL3 (IL28B) genotype and PEG interferon-α-based regimens

Pegylated interferon-α (PEG-IFN-α or PEG-IFN 2a and 2b)- and ribavirin (RBV)-based regimens are the mainstay for treatment of hepatitis C virus (HCV) genotype 1. IFNL3 (IL28B) genotype is the strongest baseline predictor of response to PEG-IFN-α and RBV therapy in previously untreated patients and can be used by patients and clinicians as part of the shared decision-making process for initiating treatment for HCV infection. We provide information regarding the clinical use of PEG-IFN-α- and RBV-containing regimens based on IFNL3 genotype.

Chronic renal allograft damage after transplantation: what are the reasons, what can we do?

PURPOSE OF REVIEW

Chronic renal allograft damage is one of the main problems after kidney transplantation. This review enumerates causes, describes available therapeutic options, and discusses options of the future.

RECENT FINDINGS

Alloantigen-dependent and alloantigen-independent factors are responsible for allograft damage. Prevention of renal allograft damage starts with interventions that occur surrounding the explantation in cadaveric organs. These include the use of dopamine or machine perfusion systems.Followed by the critical phase of ischemia/reperfusion injury, the LCN2/lipocalin-2, HAVCR1, and p38 MAPK pathway are new players involved in that process. Innate immunity plays a part, too. Cold ischemia time is associated with genes of apoptosis. Nondonor-specific antibodies like antihuman leukocyte antibodies-Ia or angiotensin type 1 receptor may also play a role. Recent research indicates that genetic polymorphism like the Ficolin-2 Ala258Ser polymorphism and the mannose-binding lectin-2 polymorphism are involved in that process. New therapeutic options are rare and in the future. However, there is some evidence that drugs interfering with metalloproteinases, sexual hormones like dihydroandrosterone, and mesenchymal stem cell therapy may be of importance.

SUMMARY

Taken together, although the understanding of chronic rejection has improved, the available therapeutic options remain scarce.