IL28B alleles associated with poor hepatitis C virus (HCV) clearance protect against inflammation and fibrosis in patients infected with non-1 HCV genotypes

Molecular mechanisms of hepatitis C virus-induced hepatocellular carcinoma

Hepatitis C virus (HCV) is a major leading cause of hepatocellular carcinoma (HCC). HCV-induced hepatocarcinogenesis is a multistep process resulting from a combination of pathway alterations that are either caused directly by viral factors or immune mediated as a consequence of a chronic state of inflammation. Host genetic variation is now emerging as an additional element that contribute to increase the risk of developing HCC. The advent of direct-acting antiviral agents foresees a rapid decline of HCC rate in HCV patients. However, a full understanding of the HCV-mediated tumourigenic process is required to elucidate if pro-oncogenic signatures may persist after virus clearance, and to identify novel tools for HCC prevention and therapy. In this review, we summarize the current knowledge of the molecular mechanisms responsible for HCV-induced hepatocarcinogenesis.

Responder Interferon λ Genotypes Are Associated With Higher Risk of Liver Fibrosis in HIV-Hepatitis C Virus Coinfection

Background. Liver fibrosis progresses faster in individuals coinfected with human immunodeficiency virus (HIV) and hepatitis C virus (HCV). Interferon λ3 (IFN-λ3) has both antiviral and proinflammatory properties. Genotypes at IFNL single-nucleotide proteins (SNPs; rs12979860CC and rs8099917TT) are linked to higher HCV clearance, potentially via rs8103142. We examined the relationship between IFN-λ genotypes and significant liver fibrosis in HIV-HCV coinfection.

Methods. From the prospective Canadian Co-infection Cohort (n = 1423), HCV RNA–positive participants in whom IFN-λ genotypes were detected and who were free of fibrosis, end-stage liver disease, and chronic hepatitis B at baseline (n = 485) were included. Time to significant fibrosis (defined as an aspartate transaminase level to platelet count ratio index [APRI] of ≥1.5) by IFN-λ genotypes was analyzed using Cox proportional hazards, with adjustment for age, sex, ethnicity, alcohol use, CD4⁺ T-cell count, HCV genotype, γ-glutamyl transferase level, and baseline APRI. Haplotype analysis was performed, with adjustment for ethnicity.

Results. A total of 125 participants developed fibrosis over 1595 person-years (7.84 cases/100 person-years; 95% confidence interval [CI], 6.58–9.34 cases/100 person-years). Each genotype was associated with an increased fibrosis risk, with adjusted hazard ratios of 1.37 (95% CI, .94–2.02) for rs12979860CC, 1.34 (95% CI, .91–1.97) for rs8103142TT, and 1.79 (95% CI, 1.24–2.57) for rs8099917TT. Haplotype TCT was also linked with a higher risk (hazard ratio, 1.14 [95% CI, .73–1.77]).

Conclusions. IFN-λ SNPs rs12979860, rs8099917, and rs81013142 were individually linked to higher rates of fibrosis in individuals with HIV-HCV coinfection. IFN-λ genotypes may be useful to target HCV treatments to people who are at higher risk of liver disease.

Interleukin-28B polymorphisms and interferon gamma inducible protein-10 serum levels in seronegative occult hepatitis C virus infection

Polymorphisms upstream interleukin (IL)-28B gene and serum levels of interferon gamma inducible protein-10 (IP-10) are associated with spontaneous and treatment-induced hepatitis C virus (HCV) clearance. Patients with seronegative occult HCV infection are anti-HCV and serum HCV-RNA negative but have viral RNA in liver and abnormal values of liver enzymes. We examined if the rs12979860 polymorphism of IL-28B and serum IP-10 levels differ between chronic and seronegative occult CV infection. IL-28B polymorphism was determined with allele specific TaqMan probes in total DNA isolated from peripheral blood mononuclear cells and IP-10 by an enzyme-linked immunosorbent assay in serum from 99 patients with seronegative occult HCV infection and 130 untreated patients with chronic hepatitis C. IL-28B genotypes were also determined in 54 healthy volunteers. Prevalence of the IL-28B CC genotype was significantly higher in seronegative occult HCV infection (52/99; 52.5%) than in chronic hepatitis C (32/130; 24.6%, P < 0.0001) or healthy controls (19/54: 32.5%, P = 0.039). Among patients with seronegative occult HCV infection, HCV-RNA load in liver was significantly lower in those with the IL-28B CC genotype than in those with CT + TT genotypes (2.8 × 10(5)  ± 5.8 × 10(4) vs. 4.1 × 10(5)  ± 5.9 × 10(4)  copies/μg of total RNA respectively; P = 0.023). Mean serum IP-10 levels were significantly lower in patients with seronegative occult HCV infection than in patients with chronic hepatitis C (160.8 ± 17.9 vs. 288.7 ± 13.3 pg/ml respectively; P < 0.0001). These findings suggest that the host immune response plays an important role in seronegative occult HCV infection in comparison with chronic hepatitis C.

Association with Spontaneous Hepatitis C Viral Clearance and Genetic Differentiation of IL28B/IFNL4 Haplotypes in Populations from Mexico

AIM

To analyze the genetic heterogeneity of the Amerindian and admixed population (Mestizos) based on the IL28B (rs12979860, rs8099917) and IFNL4 (rs368234815) haplotypes, and their association with spontaneous clearance (SC) and liver damage in patients with hepatitis C infection from West Mexico.

METHODS

A total of 711 subjects from West Mexico (181 Amerindians and 530 Mestizos) were studied for the prevalence of IL28B (rs12979860C/T, rs8099917G/T) and IFNL4 (rs368234815∆G/TT) genotypes. A case-control study was performed in 234 treatment-naïve HCV Mestizos (149 chronic hepatitis C and 85 with SC) for the association of haplotypes with SC and liver damage. A real-time PCR assay was used for genotyping, and transitional elastography staged liver damage.

RESULTS

Significant Fst-values indicated differentiation between the studied populations. The frequencies of the protective C, T, TT alleles were significantly lower in the Amerindians than in Mestizos (p<0.05). The r2 measure of linkage disequilibrium was significant for all variants and the T/G/ΔG risk haplotype predominated in Amerindians and secondly in Mestizos. The protective C/T/TT haplotype was associated with SC (OR = 0.46, 95% IC 0.22-0.95, p = 0.03) and less liver damage (OR = 0.32, 95% IC 0.10-0.97, p = 0.04) in chronic patients. The Structure software analysis demonstrated no significant differences in ancestry among SC and chronic patients.

CONCLUSIONS

West Mexico's population is genetically heterogeneous at the IL28B/IFNL4 polymorphisms. The T/G/ΔG high-risk haplotype predominated in Amerindians and the beneficial alternative haplotype in Mestizos. The C/T/TT haplotype was associated with SC and less liver damage in chronically infected Mestizo patients.

Why do I treat my patients with mild hepatitis C?

The major advances achieved in the treatment of HCV by the development of new direct-acting antiviral agents (DAAs) allow treatment of almost the entire spectrum of patients with chornic infection. As a result of the exceedingly high cost of DAAs in many countries, IFN-free DAA regimens are mostly reserved to patients with advanced fibrosis or cirrhosis. Hence, treatment of patients with milder liver disease is often deferred. This could ultimately result in an increased burden of advanced liver disease and in increased long-term costs of management. Moreover, studies performed during the 'interferon era' and the early data on interferon-free regimens show that patients without severe fibrosis achieve higher rates of sustained virological response with less treatment-related adverse events. Unfortunately, there is no univocal way to predict the progression of liver fibrosis and therefore to identify the patients with early disease who would require urgent HCV treatment. Many studies have also demonstrated that treatment-induced HCV clearance reduces all-cause mortality regardless of the stage of liver fibrosis, pointing to an effect on extrahepatic manifestations of HCV infection. Last but not least, pharmacoeconomic studies show that DAA treatment of patients with mild HCV disease is cost-effective even at high prices of drugs, thus suggesting the opprtunity to treat regardless of the stage of liver disease.

Immunopathogenesis of Hepatitis C Virus Infection

Despite advances in therapy, hepatitis C virus infection remains a major global health issue with 3 to 4 million incident cases and 170 million prevalent chronic infections. Complex, partially understood, host-virus interactions determine whether an acute infection with hepatitis C resolves, as occurs in approximately 30% of cases, or generates a persistent hepatic infection, as occurs in the remainder. Once chronic infection is established, the velocity of hepatocyte injury and resultant fibrosis is significantly modulated by immunologic as well as environmental factors. Immunomodulation has been the backbone of antiviral therapy despite poor understanding of its mechanism of action.

Association of IFNL3 and IFNL4 polymorphisms with liver-related mortality in a multiracial cohort of HIV/HCV-coinfected women

African Americans coinfected with HIV and hepatitis C virus (HCV) have lower liver-related mortality than Caucasians and Hispanics. While genetic polymorphisms near the IFNL3 and IFNL4 genes explain a significant fraction of racial differences in several HCV-related outcomes, the impact of these variants on liver-related mortality has not been investigated. We conducted a cohort study of HIV/HCV-coinfected women followed in the multicentre, NIH-funded Women's Interagency HIV Study (WIHS) to investigate whether 10 polymorphisms spanning the IFN-λ region were associated with liver-related mortality by dominant, recessive or additive genetic models. We also considered whether these polymorphisms contributed to previously reported differences in liver-related death by race/ethnicity (ascertained by self-report and ancestry informative markers). Among 794 coinfected women, there were 471 deaths including 55 liver-related deaths during up to 18 years of follow-up. On adjusted analysis, rs12980275 GG genotype compared to AG+AA hazards ratios [(HR) 0.36, 95% CI 0.14-0.90, P = 0.029] and rs8109886 AA genotype compared to CC+AC (HR 0.67, 95% CI 0.45-0.99, P = 0.047) were most strongly associated with liver-related death although these associations were no longer significant after adjusting for race/ethnicity (HR 0.41, 95% CI 0.16-1.04, P = 0.060 and HR 0.78, 95% CI 0.51-1.19, P = 0.25, respectively). African American women had persistently lower liver-related death independent of IFN-λ variants (HRs ≤ 0.44, P values ≤ 0.04). The lower risk of death among African American HIV/HCV-coinfected women is not explained by genetic variation in the IFN-λ region suggesting, that other genetic, behavioural and/or environmental factors may contribute to racial/ethnic differences in liver-related mortality.

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.

Analysis of Post-Liver Transplant Hepatitis C Virus Recurrence Using Serial Cluster of Differentiation Antibody Microarrays

BACKGROUND

Hepatitis C virus (HCV) reinfection of the liver allograft after transplantation is universal, with some individuals suffering severe disease recurrence. Predictive markers of recurrent disease severity are urgently needed. In this study, we used a cluster of differentiation (CD) microarray to predict the severity of HCV recurrence after transplantation.

METHODS

The CD antibody microarray assays of live leukocytes were performed on peripheral blood taken in the first year after transplantation. The results were grouped into phases defined as; Pre-transplant (day 0), Early (day 3 to week 2), Mid (week 4 to week 10), and Late (week 12 to week 26). Hepatitis C virus severity was based on fibrosis stages in the first 2 years (F0-1 mild and F2-4 severe).

RESULTS

Serial blood samples from 16 patients were taken before and after liver transplantation. A total of 98 assays were performed. Follow-up was 3 years or longer. Comparing recurrence severity, significantly greater numbers of CD antigens were differentially expressed on the pretransplant samples compared to any posttransplant timepoints. Five differentially expressed CD antigens before transplantation (CD27 PH, CD182, CD260, CD41, and CD34) were significantly expressed comparing severe to mild recurrence, whereas expression of only CD152 was significant in the late phase after transplantation. No relationship was observed between the donor or recipient interleukin-28B genotypes and HCV recurrence severity.

CONCLUSIONS

This study shows that circulating leukocyte CD antigen expression has utility in assessing recurrent HCV disease severity after liver transplantation and serves as a proof of principle. Importantly, pretransplant CD antigen expression is most predictive of disease outcome.

Potential genetic markers for prediction of treatment response in Egyptian children infected with HCV genotype 4

BACKGROUND

Egypt has a high prevalence of hepatitis C virus (HCV) infection. Limitations of the current HCV treatment in children are low rate of sustained virological response, significant side effects and high expenses, making prediction of treatment response crucial.

AIM

This study aimed to investigate association of single nucleotide polymorphisms (SNPs) in interleukins (IL) 10, 28 and 29 genes in predicting the response to therapy in HCV infected children.

METHODS

Sixty-six Egyptian children infected with HCV genotype 4, receiving pegylated interferon alpha 2b and ribavirin, were included. Genotyping of six SNPs in interleukin 10, 28B and 29 gene as well as HCV genotype were analyzed by real-time polymerase chain reaction.

RESULTS

The CC genotype in IL28B; rs12979860 had 8.547 folds higher chance to develop sustained virological response than CT and TT genotypes (P=0.014). Genotype distribution of rs8099917 in IL28B gene (TG and GG genotypes) was found to be 3.348 more likely not to respond to treatment than the TT genotype (P=0.018). In multivariate analysis, interleukin 28 gene single nucleotide polymorphisms rs 12979860, interleukin 10 single nucleotide polymorphisms -592A > C and basal viral load were independent variables that significantly improved prediction of response to HCV therapy.

CONCLUSION

This association can be translated into clinical decision making for HCV treatment.

Genetic Polymorphisms of IL28B and PNPLA3 Are Predictive for HCV Related Rapid Fibrosis Progression and Identify Patients Who Require Urgent Antiviral Treatment with New Regimens

The assessment of individual risk of fibrosis progression in patients with chronic hepatitis C is an unmet clinical need. Recent genome-wide association studies have highlighted several genetic alterations as predictive risk factors of rapid fibrosis progression in chronic hepatitis C. However, most of these results require verification, and whether the combined use of these genetic predictors can assess the risk of fibrosis progression remains unclear. Therefore, genetic risk factors associated with fibrosis progression were analyzed in 176 chronic hepatitis C patients who did not achieve sustained virological response by interferon-based therapy and linked to the fibrosis progression rate (FPR). FPR was determined in all patients by paired liver biopsy performed before and after therapy (mean interval: 6.2 years). Mean FPR in patients with IL28B (rs8099917) TG/GG and PNPLA3 (rs738409) CG/GG were significantly higher than in those with IL28B TT (FPR: 0.144 vs. 0.034, P < 0.001) and PNPLA3 CC (FPR: 0.10 vs. 0.018, P = 0.005), respectively. IL28B TG/GG [hazard ratio (HR): 3.9, P = 0.001] and PNPLA3 CG/GG (HR: 3.1, P = 0.04) remained independent predictors of rapid fibrosis progression upon multivariate analysis together with average alanine aminotransferase after interferon therapy ≥40 IU/l (HR: 4.2, P = 0.002). Based on these data, we developed a new clinical score predicting the risk of fibrosis progression (FPR-score). The FPR-score identified subgroups of patients with a low (FPR: 0.005), intermediate (FPR: 0.103, P < 0.001), and high (FPR: 0.197, P < 0.001) risk of fibrosis progression. In conclusion, IL28B and PNPLA3 genotypes are associated with rapid fibrosis progression, and the FPR-score identifies patients who has a high risk of fibrosis progression and require urgent antiviral treatment.

Impact of IL28B, ITPA and PNPLA3 genetic variants on therapeutic outcome and progression of hepatitis C virus infection

Chronic HCV infection comprises a broad spectrum of liver disease, ranging from no or minimal activity to active hepatitis that in time may progress to severe liver fibrosis, cirrhosis and hepatocellular carcinoma if left untreated. This review describes the impact of genetic variants of interleukin 28B (IL28B; also known as interferon-lambda 3), inosine triphosphate pyrophosphatase (ITPA) and patatin-like phospholipase domain-containing 3 (PNPLA3) on therapeutic outcome and liver disease severity in HCV-infected patients.

Host genetic variants influencing the clinical course of hepatitis C virus infection

The clinical course of hepatitis C virus (HCV) infection greatly differs in individuals. Various viral, host, and environmental factors influence the natural history of HCV infection. Recent genome-wide association studies identified several host genetic factors influencing treatment efficacy or clinical course in HCV infection. A landmark discovery was that IFNL3-IFNL4 variants are strongly associated with responses to interferon-based treatment. Genetic variants in IFNL3-IFNL4 as well as those in HLA class II loci influence the spontaneous clearance of acute HCV infection. Interestingly, these genetic variants also affect the activity of hepatitis, or disease progression in chronic hepatitis C. In addition, polymorphisms in apoptosis-related genes such as RNF7, TULP1, and MERTK are associated with fibrosis progression, and DEPDC5 and MICA variants are associated with HCV-related hepatocellular carcinoma. Understanding the genetic factors associated with the clinical course of HCV infection is essential for personalized treatment and surveillance of disease progression and hepatocellular carcinoma.

Guarding the frontiers: the biology of type III interferons

Type III interferons (IFNs) or IFN-λs regulate a similar set of genes as type I IFNs, but whereas type I IFNs act globally, IFN-λs primarily target mucosal epithelial cells and protect them against the frequent viral attacks that are typical for barrier tissues. IFN-λs thereby help to maintain healthy mucosal surfaces through immune protection, without the significant immune-related pathogenic risk associated with type I IFN responses. Type III IFNs also target the human liver, with dual effects: they induce an antiviral state in hepatocytes, but specific IFN-λ4 action impairs the clearance of hepatitis C virus and could influence inflammatory responses. This constitutes a paradox that has yet to be resolved.

Interferon-λ rs12979860 genotype and liver fibrosis in viral and non-viral chronic liver disease

Tissue fibrosis is a core pathologic process that contributes to mortality in ~45% of the population and is likely to be influenced by the host genetic architecture. Here we demonstrate, using liver disease as a model, that a single-nucleotide polymorphism (rs12979860) in the intronic region of interferon-λ4 (IFNL4) is a strong predictor of fibrosis in an aetiology-independent manner. In a cohort of 4,172 patients, including 3,129 with chronic hepatitis C (CHC), 555 with chronic hepatitis B (CHB) and 488 with non-alcoholic fatty liver disease (NAFLD), those with rs12979860CC have greater hepatic inflammation and fibrosis. In CHC, those with rs12979860CC also have greater stage-constant and stage-specific fibrosis progression rates (P<0.0001 for all). The impact of rs12979860 genotypes on fibrosis is maximal in young females, especially those with HCV genotype 3. These findings establish rs12979860 genotype as a strong aetiology-independent predictor of tissue inflammation and fibrosis.

Tissue fibrosis is a major contributor to mortality in the developed world. Here, the authors identify a genetic variant in the intronic region of interferon-λ4 that is a strong predictor of hepatic inflammation and fibrosis, independent of liver disease aetiology

Revisiting liver disease progression in HIV/HCV-coinfected patients: the influence of vitamin D, insulin resistance, immune status, IL28B and PNPLA3

BACKGROUND & AIMS

To perform a comprehensive study on independent modulators of liver fibrosis progression and determinants of portal pressure considering immune status, insulin resistance (IR), serum 25-hydroxyvitamin D (25(OH)D) levels, genetic variants of patatin-like phospholipase domain-containing protein 3 (PNPLA3) and interleukin 28B (IL28B) in a thoroughly documented cohort of HIV/hepatitis C-coinfected (HIV/HCV) patients.

PATIENTS & METHODS

25(OH)D deficiency (25(OH)DDEF), IR and low CD4(+) T-lymphocyte nadir (lowCD4NAD) were defined as 25(OH)D <20 ng × ml(-1) , HOMA-IR >2 and CD4nadir <200 cells × μl(-1) respectively. Liver fibrosis progression rate (FPR) was calculated as METAVIR F units divided by the number of years since HCV infection. Patients with a FPR > median FPR were assigned to the highFPR group.

RESULTS

Among 86 HIV/HCV, the median FPR was 0.167 units × years(-1) . While the prevalence of prior alcohol abuse, lowCD4NAD and 25(OH)DDEF was higher among highFPR patients, the prevalence of IR was comparable. The association between 25(OH)DDEF and FPR was confirmed in a subgroup of patients with METAVIR stage F0/F1/F2 in which 25(OH)D levels are not affected by the severity of liver disease. The distribution of IL28B C/C and PNPLA3 non-C/C was similar, while PNPLA3 G/G was exclusively observed in highFPR patients. LowCD4NAD (OR: 2.95; 95% CI: 1.05-8.24; P = 0.039) and 25(OH)DDEF (OR: 5.62; 95% CI: 2.05-15.38; P = 0.001) were independently associated with highFPR and showed an additive effect. Portal pressure correlated with prior alcohol abuse, HCV-genotype 3, CD4(+) nadir and 25(OH)D levels.

CONCLUSIONS

Two potentially modifiable factors, CD4(+) nadir and 25(OH)D levels, were both independent modulators of liver fibrosis progression and determinants of portal pressure. Further studies are warranted to assess the relevance of PNPLA3 for FPR in HIV/HCV.

Correlation between genetic variations and serum level of interleukin 28B with virus genotypes and disease progression in chronic hepatitis C virus infection

Recent studies have demonstrated that polymorphisms near the interleukin-28B (IL-28B) gene could predict the response to Peg-IFN-a/RBV combination therapy in HCV-infected patients. The aim of the study was to correlate the serum level of IL28B in HCV-infected patients with virus genotype/subgenotype and disease progression. IL28B serum level was detected and variations at five single nucleotide polymorphisms (SNPs) in IL28B gene region were genotyped and analyzed. The variation of IL28B genetic polymorphisms was found to be strongly associated with HCV infection when healthy control group was compared to HCV-infected patients with all P values <0.0001. Functional analysis revealed that subjects carrying rs8099917-GG genotype had higher serum level of IL28B than those with GT or TT genotypes (P = 0.04). Also, patients who were presented with cirrhosis (Cirr) only or with cirrhosis plus hepatocellular carcinoma (Cirr+HCC) had higher levels of serum IL28B when compared to chronic HCV-infected patients (P = 0.005 and 0.003, resp.). No significant association was found when serum levels of IL28B were compared to virus genotypes/subgenotypes. This study indicates that variation at SNP rs8099917 could predict the serum levels of IL28B in HCV-infected patients. Furthermore, IL28B serum level may serve as a useful marker for the development of HCV-associated sequelae.

Transmitted/founder hepatitis C viruses induce cell-type- and genotype-specific differences in innate signaling within the liver

Hepatitis C virus (HCV) infection leads to persistence in the majority of cases despite triggering complex innate immune responses within the liver. Although hepatocytes are the preferred site for HCV replication, nonparenchymal cells (NPCs) can also contribute to antiviral immunity. Recent innovations involving single-genome amplification (SGA), direct amplicon sequencing, and phylogenetic inference have identified full-length transmitted/founder (T/F) viruses. Here, we tested the effect of HCV T/F viral RNA (vRNA) on innate immune signaling within hepatocytes and NPCs, including the HepG2 and Huh 7.5.1 cell lines, a human liver endothelial cell line (TMNK-1), a plasmacytoid dendritic cell line (GEN2.2), and a monocytic cell line (THP-1). Transfection with hepatitis C T/F vRNA induced robust transcriptional upregulation of type I and III interferons (IFNs) within HepG2 and TMNK-1 cells. Both the THP-1 and GEN2.2 lines demonstrated higher type I and III IFN transcription with genotype 3a compared to genotype 1a or 1b. Supernatants from HCV T/F vRNA-transfected TMNK-1 cells demonstrated superior viral control. Primary human hepatocytes (PHH) transfected with genotype 3a induced canonical pathways that included chemokine and IFN genes, as well as overrepresentation of RIG-I (DDX58), STAT1, and a Toll-like receptor 3 (TLR3) network. Full-length molecular clones of HCV induce broad IFN responses within hepatocytes and NPCs, highlighting that signals imparted by the various cell types within the liver may lead to divergent outcomes of infection. In particular, the finding that HCV genotypes differentially induce antiviral responses in NPCs and PHH might account for relevant clinical-epidemiological observations (higher clearance but greater necroinflammation in persistence with genotype 3).

IMPORTANCE

Hepatitis C virus (HCV) has become a major worldwide problem, and it is now the most common viral infection for which there is no vaccine. HCV infection often leads to persistence of the virus and is a leading cause of chronic hepatitis, liver cancer, and cirrhosis. There are multiple genotypes of the virus, and patients infected with different viral genotypes respond to traditional therapy differently. However, the immune response to the virus within the liver has not been fully elucidated. Here, we determined the responses to different genotypes of HCV in cell types of the liver. We found that the immune response varied according to both cell type and HCV genotype, leading to a more pronounced induction of inflammatory pathways after exposure to certain genotypes. Therefore, inflammatory pathways that are being robustly activated by certain HCV genotypes could lead to more severe damage to the liver, inducing diverse outcomes and responses to therapy.

Interleukin-28B genetic variants in untreated Italian HCV-infected patients: a multicentre study

BACKGROUND & AIMS

Different prevalence of favourable IL28BCC genotype have been reported in studies performed in different countries around the world. Data on distribution of IL28B genotypes in healthy Italian subjects are lacking.

METHODS

Studies on prospectively collected untreated chronic HCV-infected Italian patients led to conflicting results. To investigate the prevalence of IL28B genotypes in untreated HCV-infected patients and in subjects able to clear HCV, and to compare them to the prevalence registered in healthy Italian controls. To evaluate IL28B prevalence across different HCV genotypes.

RESULTS

IL28BCC was observed in 30.9% of chronic HCV patients, in 71.0% of subjects able to clear HCV infection and in 41.6% of the Italian controls. The frequency of IL28BCC was higher in HCV genotype 2 and 3 than in 1 (38.3 vs. 28.2) (P = 0.02). Levels of ALT higher in IL28BCC than in non-CC were observed regardless of HCV genotypes (P = 0.0014).

CONCLUSIONS

IL28BCC frequencies progressively decline from subjects with spontaneous HCV clearance to normal non-infected subjects and to chronically infected. This study suggests that patients with IL28BCC, if genotype 1, are able to clear HCV more often than if genotype 2 and 3 infected, and that CC genotype is associated with higher grade of necro-inflammation.

Interferon lambda-3 is not associated with clinical outcome in patients with HCV-induced compensated cirrhosis: a long-term cohort study

BACKGROUND

Interferon Lambda-3 (IFN-λ3) gene polymorphism is associated with spontaneous clearance of hepatitis C virus (HCV) and response to IFN-based therapy (IFN). However, very few data are available about its value in predicting sustained virologic response (SVR) in patients with cirrhosis, and whether IFN-λ3 genotype influences liver disease progression remains unclear.

METHODS

We determined IFN-λ3 genotype by PCR in a cohort of patients with compensated HCV-related cirrhosis, enrolled between 1989 and 1992. Person-years follow-up was calculated for each individual from the date of enrolment to the development of first episode of decompensation, HCC, liver transplant, death or end of follow-up. The follow-up of patients who achieved SVR was censored at the time of IFN initiation. Kaplan-Meier curves and Cox regression analyses were used to assess the association between IFN-λ3 genotype and clinical outcome.

RESULTS

IFN-λ3 was determined in 264 patients (52% males, mean age 57±8 years, 67% HCV genotype (G)1, while CC, CT and TT genotypes were 36%, 50% and 14%, respectively. During a median follow-up of 14.8 years, 149 (56%) patients received IFN. Overall, SVR was achieved in 31 (21%) patients, 40% among those with CC genotype (22% in G1 and 61% in G2, respectively) compared to 10% and 13% among patients with CT and TT genotypes (p<0.0001). Univariate and multivariate analyses found no association between IFN-λ3 (CC vs. non-CC genotype) and disease progression.

CONCLUSION

IFN-λ3 determination is fundamental for allocating cirrhotic patients to be treated with IFN, while it has no value in predicting the outcome of the disease.

Genetic variation in interleukin 28B and correlation with chronic hepatitis B virus infection in Saudi Arabian patients

BACKGROUND & AIMS

Several genome-wide association studies have shown that genetic variations in the chromosomal region containing interleukin-28B (IL28B) gene are associated with response to treatment in hepatitis C virus (HCV) infection. This study was conducted to examine the role of genetic variations in IL28B on disease progression in Saudi Arabian patients chronically infected with hepatitis B virus (HBV).

METHODS

The study included 1128 subjects divided into four categories; 304 clearance subjects, 518 inactive carriers, 212 active carriers and 94 cirrhosis/HCC.

RESULTS

Three single nucleotide polymorphisms (SNPs), rs12979860 (OR=1.307; 95% CI 1.046-1.634, χ2=5.57 and P=0.0183), rs12980275 (OR=0.642; CI 0.517-0.798, χ2=16.17 and P=0.0001) and rs8105790 (OR=0.746; CI 0.592-0.941, χ2=6.12 and P=0.0133), were found to be strongly associated with HBV clearance. The frequency of the G allele of rs12980275 and the C allele of rs8105790 were found to be more in clearance group than in patients and could contribute to protection against the disease. On the other hand, only rs12979860 showed significant difference in distribution when inactive group was compared to other groups (OR=1.285; CI 1.030-1.603, χ2=4.95, P=0.0261). No significant association was evident for any of the variants when active carriers were compared to cirrhosis/HCC patients. Haplotype analysis showed that a combination of A-T-T-G of rs12980275, rs8105790, rs8099917, and rs7248668, respectively, was associated with clearance of the virus (frequency=67.5% and P=0.015).

CONCLUSION

genetic variations in IL28B gene region may influence the clearance of HBV infection.

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.

IFNL3 (IL28B) polymorphism does not predict long-term response to interferon therapy in HBeAg-positive chronic hepatitis B patients

The impact of IFNL3 (IL28B) polymorphism on response to interferon (IFN) treatment in patients infected with hepatitis B virus (HBV) is controversial. We aimed to investigate whether IFNL3 polymorphism (rs12979860) influences the long-term response of chronic hepatitis B (CHB) treatment to conventional IFN.

DESIGN

Ninety-seven HBeAg-positive patients treated with IFN were evaluated in this study. Associations were investigated between IFNL3 genotypes and (i) HBeAg seroconversion at the end of treatment (EOT), (ii) sustained virological response (SVR) and (iii) HBsAg seroconversion through long-term follow-up (LTFU). Patients were followed for a median of 14 years. The majority of patients were infected with HBV genotype A (69.6%) and were Caucasian (77.9%). Ninety-five patients were genotyped at rs12979860. Similar IFNL3 distribution was observed among the different ethnicities (P = 0.62) or across HBV genotypes A through G (P = 0.70). Thirty-six patients experienced HBeAg seroconversion at EOT; HBeAg seroconversion rates were 37.0 and 35.5% in patients with CC and CT/TT genotypes, respectively (P = 0.82). Among the 44 patients (45%) who achieved a SVR, SVR rates were 48.9 and 39.6% in patients with CC and CT/TT IL28B genotypes, respectively (P = 0.80). HBsAg seroconversion occurred through LTFU in 28 patients. HBsAg seroconversion rates were 25.5 and 31.2% in patients with CC and CT/TT genotypes, respectively (P = 0.51). No significant relationship between IFNL3 rs12979860 and fibrosis stage was observed (P = 0.85). IFNL3 genotype was neither associated with SVR, nor with HBeAg seroconversion and long-term HBsAg seroconversion in HBeAg-positive CHB patients responding to IFN therapy.

Is genotype 3 of the hepatitis C virus the new villain?

Genotype 3 of the hepatitis C virus (HCV) has been long considered an easy-to-treat infection, with higher cure rates (∼70%) than other viral genotypes with the standard combination of pegylated interferon-α and ribavirin. However, the relative insensitivity of this genotype to most protease inhibitors and the recent unexpected data on decreased effectiveness of sofosbuvir have raised questions on how to achieve universal cure, a goal that seems reasonable for other genotypes. In addition, increasing clinical and experimental data show that HCV genotype 3 may be associated not only with severe steatosis, but also with accelerated fibrosis progression rate and increased oncogenesis.

CONCLUSION

Currently available data suggest that we should increase our efforts to understand the virology and pathogenesis of HCV genotype 3, aiming at better and more potent, genotype-targeted treatments.

Reduction of microRNA 122 expression in IFNL3 CT/TT carriers and during progression of fibrosis in patients with chronic hepatitis C

The microRNA miR-122 is highly expressed in the liver and stimulates hepatitis C virus (HCV) replication in vitro. IFNL3 (lambda-3 interferon gene) polymorphisms and the expression of miR-122 have been associated with sustained virological response (SVR) to treatment with pegylated interferon plus ribavirin in patients with chronic hepatitis C (CHC). We investigated, in vivo, the relationship between miR-122 expression, IFNL3 polymorphism, fibrosis, and response to PEG-IFN plus ribavirin. Pretreatment liver biopsy specimens and serum samples from 133 patients with CHC were included. Sixty-six patients achieved SVR, and 64 failed to respond to the treatment (43 nonresponders [NR] and 21 relapsers [RR]). All stages of fibrosis were represented, with 39, 50, 23, and 19 patients, respectively, having Metavir scores of F1, F2, F3, and F4. miR-122 expression was assessed by real-time quantitative PCR (RT-qPCR) and IFNL3 rs12979860 by direct sequencing. Hepatic miR-122 expression was higher in patients with the IFNL3 CC genotype than in those with the IFNL3 CT or TT genotype, in all patients (P = 0.025), and in NRs plus RRs (P = 0.013). Increased hepatic miR-122 was more strongly associated with complete early virological response (cEVR) (P = 0.003) than with SVR (P = 0.016). In multivariate analysis, increased hepatic miR-122 was only associated with the IFNL3 CC genotype. miR-122 was decreased in patients with advanced fibrosis (Metavir scores of F3 and F4) compared to its levels in patients with mild and moderate fibrosis (F1 and F2) (P = 0.01). Serum and hepatic expression of miR-122 were not associated. The association between miR-122 and IFNL3 was stronger than the association between miR-122 and response to treatment. miR-122 may play a role in the early viral decline that is dependent on IFNL3 and the innate immune response.

IMPORTANCE

miR-122 plays a crucial role during HCV infection. Moreover, it was reported that miR-122 binding within the HCV genome stimulates its replication. Moreover, miR-122 is highly expressed within hepatocytes, where it regulates many cellular pathways. A reduction of miR-122 expression has been suggested to be associated with responsiveness to IFN-based therapy in patients with chronic hepatitis C. Several independent genome-wide association studies reported a strong association between IFNL3 polymorphism and responsiveness to IFN-based therapy. We report here a strong association between the expression of miR-122 and IFNL3 polymorphism that is independent of the response to the treatment. Our data suggest that modification of miR-122 expression may play an important role in the molecular mechanism associated with IFNL3 polymorphism. Moreover, we report a reduction of miR-122 at more advanced stages of fibrosis in patients with chronic hepatitis C.

The association of IL28B genotype with the histological features of chronic hepatitis C is HCV genotype dependent

The interleukin 28B (IL28B) rs12979860 polymorphism is associated with treatment outcome in hepatitis C virus (HCV) genotype 1 and 4 patients. Its association with the histological features of chronic hepatitis C and disease severity needs further clarifications. To assess the correlation between IL28B genotype, HCV genotype and liver biopsy findings in untreated patients.

MATERIALS AND METHODS

Pre-treatment liver biopsies from 335 HCV Caucasian patients (59% males, age 50 years) enrolled in the MIST study were staged for fibrosis and inflammation according to the METAVIR and the Ishak scoring systems; steatosis was dichotomized as <5% or ≥5%. IL28B was typed by Taqman Single Nucleotide Polymorphism (SNP) genotyping assay. HCV genotype was 1 in 151 (45%), 2 in 99 (30%), 3 in 50 (15%) and 4 in 35 (10%) patients. IL28B genotype was CC in 117 (34%), CT in 166 (49%) and TT in 52 (15%). At univariate analysis, the IL28B CC genotype was associated with severe portal inflammation in HCV-1 patients (CC vs.

CT/TT

86% vs. 63%, p = 0.005), severe lobular inflammation in HCV-2 patients (CC vs.

CT/TT

44% vs. 23%, p = 0.03), and less fatty infiltration in HCV-1 patients (CC vs.

CT/TT

72% vs. 51%, p = 0.02). Despite the lack of any association between IL28B and fibrosis stage, in HCV-3 patients IL28B CC correlated with METAVIR F3-F4 (CC vs.

CT/TT

74% vs. 26%, p = 0.05). At multivariate analysis, the genotype CC remained associated with severe portal inflammation in HCV-1, only (Odds Ratio (OR): 95% Confidence Interval (CI): 3.24 (1.23-8.51)). IL28B genotype is associated with the histological features of chronic hepatitis C in a HCV genotype dependent manner, with CC genotype being independently associated with severe portal inflammation.

Reversal, maintenance or progression: what happens to the liver after a virologic cure of hepatitis C?

A sustained virological response (SVR) from HCV (synonymous with virological cure) leads to decreased mortality, morbidity and improved quality of life, as well as a reduced incidence of liver disease progression, including liver failure, cirrhosis and hepatocellular carcinoma. Large clinical trials comparing pre- and post-treatment liver biopsies demonstrate improvements in inflammation as well as fibrosis score following SVR. However, a small subset of patients display persistent hepatic inflammation and/or progress to cirrhosis despite SVR. In addition to conferring a risk of fibrosis progression, advanced fibrosis pre-treatment is a major risk factor for post-SVR hepatocellular carcinoma. In this review, we discuss the mechanisms of fibrosis regression uncovered using experimental fibrosis models and highlight potential mechanisms in those few patients with fibrosis progression despite SVR. We also introduce current concepts of fibrosis-dependent tumorigenesis post-SVR in patients with advanced disease. This article forms part of a symposium in Antiviral Research on "Hepatitis C: next steps toward global eradication."

Kinetic differences in the induction of interferon stimulated genes by interferon-α and interleukin 28B are altered by infection with hepatitis C virus

Several genome-wide association studies (GWAS) have identified a genetic polymorphism associated with the gene locus for interleukin 28B (IL28B), a type III interferon (IFN), as a major predictor of clinical outcome in hepatitis C. Antiviral effects of the type III IFN family have previously been shown against several viruses, including hepatitis C virus (HCV), and resemble the function of type I IFN including utilization of the intracellular Janus kinase signal transducer and activator of transcription (JAK-STAT) pathway. Effects unique to IL28B that would distinguish it from IFN-α are not well defined. By analyzing the transcriptomes of primary human hepatocytes (PHH) treated with IFN-α or IL28B, we sought to identify functional differences between IFN-α and IL28B to better understand the roles of these cytokines in the innate immune response. Although our data did not reveal distinct gene signatures, we detected striking kinetic differences between IFN-α and IL28B stimulation for interferon stimulated genes (ISGs). While gene induction was rapid and peaked at 8 hours of stimulation with IFN-α in PHH, IL28B produced a slower, but more sustained increase in gene expression. We confirmed these findings in the human hepatoma cell line Huh7.5.1. Interestingly, in HCV-infected cells the rapid response after stimulation with IFN-α was blunted, and the induction pattern resembled that caused by IL28B.

CONCLUSION

The kinetics of gene induction are fundamentally different for stimulations with either IFN-α or IL28B in hepatocytes, suggesting distinct roles of these cytokines within the immune response. Furthermore, the observed differences are substantially altered by infection with HCV.

A polymorphism linked to RRAS, SCAF1, IRF3 and BCL2L12 genes is associated with cirrhosis in hepatitis C virus carriers

BACKGROUND & AIMS

Host genetic factors could play a primary role in determining risk for cirrhosis development in HCV-infected patients. The aims of this study were to discover new genetic variants associated with this trait and to replicate some associations formerly reported.

METHODS

Three hundred and thirty-seven HCV carriers with available data about liver fibrosis status, who initiated treatment with pegylated interferon plus ribavirin, were included. Of them, 77 (22.85%) were cirrhotic. One hundred and forty-four SNPs from 40 genes related to cholesterol metabolism/transport, sustained viral response to HCV therapy, liver fibrosis, or immune response, were genotyped in all samples. Plink software was used to perform univariate association analyses. The results obtained were adjusted by other parameters related to cirrhosis using multivariate logistic regression models.

RESULTS

Only the SNP rs12104272, linked to RRAS, SCAF1, IRF3 and BCL2L12 genes, was associated with cirrhosis. It was observed a higher proportion of rs12104272 A allele carriers in the non-cirrhotic group (60.63%) than in the cirrhotic group (38.15%) (adjusted OR = 0.36, 95% CI = 0.180-0.746, P = 0.006). This effect was stronger in the background of rs12979860 CC genotype of IL28B (adjusted OR = 0.069, 95% CI = 0.014-0.349, P = 0.001).

CONCLUSION

The rs12104272 SNP could have clinical value to select those individuals at lower risk for cirrhosis development.

IL28B minor allele is associated with a younger age of onset of hepatocellular carcinoma in patients with chronic hepatitis C virus infection

BACKGROUND

IL28B polymorphisms were shown to be associated with a response to peg-interferon-based treatment in chronic hepatitis C (CHC) and spontaneous clearance. However, little is known about how this polymorphism affects the course of CHC, including the development of hepatocellular carcinoma (HCC). We evaluated the influence of IL28B polymorphisms on hepatocarcinogenesis in CHC patients.

METHODS

We genotyped the rs8099917 single-nucleotide polymorphism in 351 hepatitis C-associated HCC patients without history of IFN-based treatment, and correlated the age at onset of HCC in patients with each genotype.

RESULTS

Frequencies of TT, TG, and GG genotypes were 74.3 % (261/351), 24.8 % (87/351), and 0.9 % (3/351), respectively. The mean ages at onset of HCC for TT, TG, and GG genotypes were 69.9, 67.5 and 66.8, respectively. In multivariate analysis, IL28B minor allele (TG and GG genotypes) was an independent risk factor for younger age at onset of HCC (P = 0.02) in males (P < 0.001) with higher body mass index (BMI; P = 0.009). The IL28B minor allele was also associated with a lower probability of having aspartate aminotransferase-to-platelet ratio index (APRI) >1.5 (minor vs. major, 46.7 vs. 58.6 %; P = 0.01), lower AST (69.1 vs. 77.7 IU/L, P = 0.02), lower ALT (67.8 vs. 80.9 IU/L, P = 0.002), higher platelet count (12.8 vs. 11.2 × 10(4)/μL, P = 0.002), and higher prothrombin time (79.3 vs. 75.4 %, P = 0.002).

CONCLUSIONS

The IL28B minor allele was associated with lower inflammatory activity and less progressed fibrosis of the liver; however, it constituted a risk factor for younger-age onset of HCC in CHC patients.

Impact of IL28B genetic variation on HCV-induced liver fibrosis, inflammation, and steatosis: a meta-analysis

BACKGROUND & AIMS

IL28B polymorphisms were shown to be strongly associated with the response to interferon therapy in chronic hepatitis C (CHC) and spontaneous viral clearance. However, little is known about how these polymorphisms affect the natural course of the disease. Thus, we conducted the present meta-analysis to assess the impact of IL28B polymorphisms on disease progression.

METHODS

A literature search was conducted using MEDLINE, EMBASE, and the Cochrane Library. Integrated odds ratios (OR) were calculated with a fixed-effects or random-effects model based on heterogeneity analyses.

RESULTS

We identified 28 studies that included 10,024 patients. The pooled results indicated that the rs12979860 genotype CC was significantly associated (vs. genotype CT/TT; OR, 1.122; 95%CI, 1.003-1.254; P = 0.044), and that the rs8099917 genotype TT tended to be (vs. genotype TG/GG; OR, 1.126; 95%CI, 0.988-1.284; P = 0.076) associated, with an increased possibility of severe fibrosis. Both rs12979860 CC (vs. CT/TT; OR, 1.288; 95%CI, 1.050-1.581; P = 0.015) and rs8099917 TT (vs. TG/GG; OR, 1.324; 95%CI, 1.110-1.579; P = 0.002) were significantly associated with a higher possibility of severe inflammation activity. Rs8099917 TT was also significantly associated with a lower possibility of severe steatosis (vs. TG/GG; OR, 0.580; 95%CI, 0.351-0.959; P = 0.034), whereas rs12979860 CC was not associated with hepatic steatosis (vs. CT/TT; OR, 1.062; 95%CI, 0.415-2.717; P = 0.901).

CONCLUSIONS

IL28B polymorphisms appeared to modify the natural course of disease in patients with CHC. Disease progression seems to be promoted in patients with the rs12979860 CC and rs8099917 TT genotypes.

IL28RA polymorphism (rs10903035) is associated with insulin resistance in HIV/HCV-coinfected patients

Hepatitis C virus (HCV) infection is associated with insulin resistance (IR), although mechanisms leading to IR in these patients are not completely understood. The aim of this study was to evaluate the association of interleukin 28B (IL28B) and interleukin 28 receptor alpha (IL28RA) polymorphisms with IR among human immunodeficiency virus (HIV)/HCV-coinfected patients. We carried out a cross-sectional study on 203 patients. IL28B (rs8099917) and IL28RA (rs10903035) polymorphisms were genotyped by GoldenGate(®) assay. IR was defined as homeostatic model assessment (HOMA) values ≥3.00. Univariate and multivariate generalized linear models (GLM) were used to compare HOMA values and the percentage of patients with IR according to IL28B and IL28RA genotypes. In total, 32% (n = 65/203) of the patients had IR. IL28B rs8099917 TT was not significantly associated with HOMA values and IR. In contrast, rs10903035 AA was significantly associated with high HOMA values taking into account all patients (P = 0.024), as well as the subgroups of patients with significant fibrosis (P = 0.047) and infected with HCV genotype 3 (P = 0.024). Additionally, rs10903035 AA was significantly associated with IR (HOMA ≥3.00) in all patients (adjusted odds ratio (aOR) = 2.02; P = 0.034), in patients with significant fibrosis (aOR = 2.86; P = 0.039) and HCV genotype 3 patients (aOR = 4.89; P = 0.031). In conclusions, IL28RA polymorphism (rs10903035) seems to be implicated in the glucose homeostasis because AA genotype increases the likelihood of IR, but this association was different depending on hepatic fibrosis and HCV genotype.

Hepatic metallothionein expression in chronic hepatitis C virus infection is IFNL3 genotype-dependent

The IFNL3 genotype predicts the clearance of hepatitis C virus (HCV), spontaneously and with interferon (IFN)-based therapy. The responder genotype is associated with lower expression of interferon stimulated genes (ISGs) in liver biopsies from chronic hepatitis C patients. However, ISGs represent many interacting molecular pathways, and we hypothesised that the IFNL3 genotype may produce a characteristic pattern of ISG expression explaining the effect of genotype on viral clearance. For the first time, we identified an association between a cluster of ISGs, the metallothioneins (MTs) and IFNL3 genotype. Importantly, MTs were significantly upregulated (in contrast to most other ISGs) in HCV-infected liver biopsies of rs8099917 responders. An association between lower fibrosis scores and higher MT levels was demonstrated underlying clinical relevance of this association. As expected, overall ISGs were significantly downregulated in biopsies from subjects with the IFNL3 rs8099917 responder genotype (P=2.38 × 10(-7)). Peripheral blood analysis revealed paradoxical and not previously described findings with upregulation of ISGs seen in the responder genotype (P=1.00 × 10(-4)). The higher MT expression in responders may contribute to their improved viral clearance and MT-inducing agents may be useful adjuncts to therapy for HCV. Upregulation of immune cell ISGs in responders may also contribute to the IFNL3 genotype effect.

Genetic predisposition in NAFLD and NASH: impact on severity of liver disease and response to treatment

Liver fat deposition related to systemic insulin resistance defines non-alcoholic fatty liver disease (NAFLD) which, when associated with oxidative hepatocellular damage, inflammation, and activation of fibrogenesis, i.e. non-alcoholic steatohepatitis (NASH), can progress towards cirrhosis and hepatocellular carcinoma. Due to the epidemic of obesity, NAFLD is now the most frequent liver disease and the leading cause of altered liver enzymes in Western countries. Epidemiological, familial, and twin studies provide evidence for an element of heritability of NAFLD. Genetic modifiers of disease severity and progression have been identified through genome-wide association studies. These include the Patatin-like phosholipase domain-containing 3 (PNPLA3) gene variant I148M as a major determinant of inter-individual and ethnicity-related differences in hepatic fat content independent of insulin resistance and serum lipid concentration. Association studies confirm that the I148M polymorphism is also a strong modifier of NASH and progressive hepatic injury. Furthermore, a few large multicentre case-control studies have demonstrated a role for genetic variants implicated in insulin signalling, oxidative stress, and fibrogenesis in the progression of NAFLD towards fibrosing NASH, and confirm that hepatocellular fat accumulation and insulin resistance are key operative mechanisms closely involved in the progression of liver damage. It is now important to explore the molecular mechanisms underlying these associations between gene variants and progressive liver disease, and to evaluate their impact on the response to available therapies. It is hoped that this knowledge will offer further insights into pathogenesis, suggest novel therapeutic targets, and could help guide physicians towards individualised therapy that improves clinical outcome.

SNP rs8099917 in gene IL28B might be associated with risk of chronic infection by HCV but not with response to treatment

AIM

The aim of this study was to characterize the genetic profile of patients with chronic hepatitis C virus (HCV) infection relative to polymorphisms rs12979860 and rs8099917 in gene IL28B and the association of those polymorphisms with the response to treatment with pegylated interferon and ribavirin, performed at a reference center in Brazilian Amazonia.

METHODS

A total of 75 individuals with chronic hepatitis C and 98 healthy individuals from both genders over 18 years old were assessed. DNA samples were collected from leukocytes and subjected to real-time polymerase chain reaction to genotype polymorphisms rs12979860 and rs8099917.

RESULTS

Analysis of the allelic and genotypic frequencies of the investigated polymorphisms showed that both groups were in Hardy-Weinberg equilibrium; polymorphism rs12979860 exhibited no significant difference between the groups. For polymorphism rs8099917, allele T was significantly less frequent (P = 0.0195) among the patients (63.3%) than the controls (75.5%), and the patients were 1.7 times as likely to exhibit allele G. No difference in response to treatment was associated with SNP patterns.

CONCLUSION

The results suggest a possible association of SNP rs8099917 with higher odds of chronic HCV infection but do not indicate a putative influence of the investigated SNPs on the sustained virologic response.

Liver fibrosis progression at autopsy in injecting drug users infected by hepatitis C: a longitudinal long-term cohort study

BACKGROUND & AIMS

There is a paucity of unbiased data on the natural history of hepatitis C virus (HCV) infection in injecting drug users (IDUs). The purpose of this study was to assess the risk of developing advanced fibrosis associated with chronic hepatitis C (CHC) infection among injecting drug users (IDUs) who underwent an autopsy.

METHODS

A longitudinal cohort design was applied, in which the stage of liver fibrosis in anti-HCV positive IDUs with or without chronic HCV infection was assessed in liver tissue from autopsies performed up to 35 years after HCV exposure. The cohort originated from 864 IDUs consecutively admitted for drug abuse treatment 1970-1984. Stored sera, mostly drawn at the time of admission for drug treatment, were available in 635 subjects. 220 out of 523 anti-HCV positive subjects had died before 2009. Liver tissue from autopsies was available from 102/220 subjects, of which 61 were HCV RNA positive. Liver sections were classified according to METAVIR scores for fibrosis. Two pathologists, both blinded for serologic results, scored sections of liver tissue.

RESULTS

Among HCV RNA positive subjects 16.4% (10/61) had septal fibrosis (F3) or cirrhosis (F4) compared to 2.4% (1/41) among anti HCV positive/HCV RNA negative subjects (p=0.026). Of 18 HCV RNA positive subjects autopsied <15 years after HCV exposure none had F3 or F4. Among subjects autopsied >25 years after exposure 35% (6/17) had F3-F4.

CONCLUSIONS

Among IDUs chronically infected by HCV, 1/3 developed septal fibrosis or cirrhosis 25 years or more after exposure.

Role of IL28B for chronic hepatitis C treatment toward personalized medicine

Genome-wide association studies recently revealed that certain interleukin-28B (IL28B) polymorphisms are strongly associated with responses to pegylated interferon (PEG-IFN) and ribavirin (RBV) therapy in patients chronically infected with hepatitis C virus (HCV) genotype 1, as well as with spontaneous clearance of HCV. Subsequent reports revealed that IL28B genotypes also affect treatment efficacy in chronic infection with other HCV genotypes. Furthermore, there have been several reports that implicate IL28B genotypes in inflammatory status, progression of fibrosis and adverse clinical outcomes in chronic hepatitis C (CHC). Therapy of CHC recently entered a new era with the deployment of direct-acting antivirals. These include nonstructural 3/4A protease inhibitors which have shown promise in combination with PEG-IFN/RBV in several clinical trials. IFN-free therapy is expected to be useful especially in IFN-resistant patients and may become the standard of care in the future. Several clinical trials have revealed an association between IL28B genotype and treatment efficacy in triple therapy or IFN-free regimens. On the other hand the mechanism of the effect of IL28B on HCV infection has not yet been elucidated. Recently, it was shown that the polymorphism of IFN-lambda 4 (IFNL4) is in high linkage disequilibrium with that of near IL28B, and more strongly associated with spontaneous or treatment-induced HCV clearance than IL28B genotypes, especially in individuals of African ancestry. This finding provides new insights into the genetic regulation of HCV clearance and its clinical management. IL28B genotyping will be also useful for personalized CHC treatment in the forthcoming era of direct-acting antivirals.

The novel ss469415590 variant predicts virological response to therapy in patients with chronic hepatitis C virus type 1 infection

BACKGROUND

A novel dinucleotide variant TT/∆G (ss469415590) has been associated with hepatitis C virus clearance.

AIM

To assess the role of the ss469415590 variant, compared with the known IL28B polymorphisms (rs8099917, rs12979860 and rs12980275) for predicting virological response to therapy in chronic hepatitis C, and its association with the CXCL10 chemokine serum levels - a surrogate marker of interferon-stimulated genes activation.

METHODS

Multivariate analysis of factors predicting rapid and sustained virological response in 280 consecutive, treatment-naïve, nondiabetic, Caucasian patients with chronic hepatitis C treated with peginterferon alpha and ribavirin.

RESULTS

In hepatitis C virus genotype 1, the OR (95% CI) for rapid and sustained virological response for the wild-type ss469415590 TT was 9.88 (1.99-48.99) and 7.25 (1.91-27.51), respectively, similar to those found for rs12979860 CC [9.55 (1.93-47.37) and 6.30 (1.71-23.13)] and for rs12980275 AA [9.62 (1.94-47.77] and 7.83 (2.02-30.34)], but higher than for rs8099917 TT [4.8 (1.73-13.33) and 4.75 (2.05-10.98)]. In hepatitis C virus genotype 1, mean (SD) CXCL10 levels in patients with the TT/TT, TT/∆G and ∆G/∆G variants were, respectively, 355.1 (240.6), 434.4 (247.4) and 569.9 (333.3) (P = 0.04). In patients with genotypes 2 and 3 no significant association was found for TT/∆G with viral response. The predictive value of ss469415590 was stronger in patients with advanced fibrosis.

CONCLUSIONS

The novel IL28B variants at marker ss469415590 predict response to IFN alpha in chronic hepatitis C patients, especially in those with advanced fibrosis. Their determination may be superior to that of known IL28B variants for patient management using IFN-based regimens.

Prediction of hepatic fibrosis in patients coinfected with HIV and hepatitis C virus based on genetic markers

OBJECTIVE

To assess the ability of the cirrhosis risk score (CRS) to predict liver fibrosis progression in HIV/hepatitis C virus (HCV)-coinfected patients.

DESIGN

Retrospective follow-up study.

METHODS

Based on a minimum follow-up time of 10 years with HCV infection, 190 HIV/HCV-coinfected patients were classified according to their METAVIR score: (1) 25 nonprogressor patients who did not develop fibrosis (F0) and (2) 165 progressor patients who developed fibrosis (F ≥ 1). Seven polymorphisms of CRS signature and IL28B genotype were performed using the GoldenGate assay. The CRS signature was calculated by naive Bayes formula as previously described.

RESULTS

Nonprogressors had CRS values significantly lower than progressors (0.61 versus 0.67; P = 0.043). Among the progressors, we observed similar CRS values through all the fibrosis stages (F1/F2/F3/F4). The percentage of patients with CRS > 0.70 (high risk of developing fibrosis) was higher in progressors than in nonprogressors; but the percentages with values between 0.50 and 0.70 (intermediate risk) and <0.50 (low risk) were quite similar for each of the fibrosis stages (P = 0.047). The area under the receiver-operating characteristic curve of CRS for discriminating nonprogressor versus progressor was 0.625 (P = 0.043). When clinical variables were considered (age at HCV infection, intravenous drug use, gender, IL28B, and HCV genotype), the area under the receiver-operating characteristic curve of CRS improved up to 0.739 (P < 0.001).

CONCLUSIONS

CRS itself seems not to be a good marker for identifying HIV/HCV-coinfected patients who are at high risk of developing liver fibrosis. However, CRS score coupled with clinical factors might help to distinguish between nonprogressors and progressors patients.

Interleukin 28B gene polymorphisms in hepatitis C virus-related cryoglobulinemic vasculitis

OBJECTIVE

Single-nucleotide polymorphisms (SNP) in the interleukin 28B (IL-28B) gene region are strongly predictive of the response of infected patients to antiviral therapy for hepatitis C virus (HCV). We sought to determine the prevalence of SNP IL-28B rs12979860 C/C and non-C/C (C/T plus T/T) genotypes in HCV-related cryoglobulinemic vasculitis (CV), as compared with HCV-positive patients without CV. We also searched for their association with peculiar clinical manifestations of CV and potential influence on the complete response (virological, molecular, and immunological) to the therapy.

METHODS

The study cohort comprised 159 and 172 HCV-infected patients with and without CV, respectively, prospectively followed starting from 1990. SNP rs12979860 genotyping was performed by Taq-Man allelic discrimination. In 106 patients (66.6%) with CV, the profile of circulating B cell clonalities was determined as well. All patients with CV were treated with pegylated interferon-α/ribavirin-based antiviral therapy.

RESULTS

The T/T IL-28B genotype was more common in patients with CV than in those without (17% vs 8.1%, p = 0.02). In patients with CV, compared with non-C/C variants, the IL-28B C/C genotype was associated with a higher rate of complete response (52.6% vs 39.2%, p = 0.13), whereas a treatment response of 61.4% was demonstrated when solely virological response was considered (p = 0.008). A higher frequency of expanded B cell clonalities in the circulation (84.2% vs 55.9%; p = 0.005), kidney involvement (21% vs 2.9%; p = 0.003), and B cell non-Hodgkin lymphoma (17.5% vs 6.8%; p = 0.048), were also observed.

CONCLUSION

In HCV-positive patients with CV, the IL-28B C/C genotype is distinguished biologically by a higher frequency of restriction of B cell response and clinically by a higher risk of cryoglobulinemic nephropathy and B cell malignancies, while acting as an independent predictor of a sustained virological response to antiviral therapy. In addition, we found that IL-28B T/T variant was more prevalent in patients with CV than in those without.

Interleukin-28B rs12979860 C allele: Protective against advanced fibrosis in chronic hepatitis C genotype 1 infection

Background and Aim: While genetic polymorphisms upstream of the interleukin-28B(IL28B) gene are associated with necroinflammatory activity grade in chronic hepatitis C virus genotype 1 (HCV-1) infection, any association with fibrosis is less definitive. Pretreatment liver biopsies in a cohort of treatment-naïve patients with HCV-1 were analyzed to evaluate associations between liver histology, and the rs12979860 and rs8099917 IL28B single nucleotide polymorphisms.Methods: Two hundred sixty-six patients with HCV-1 infection and pretreatment liver biopsy were tested for the rs12979860 and rs8099917 single nucleotide polymorphisms.Predictors of advanced fibrosis (METAVIR F3/4) and high activity grade (A2/3) were identified using multivariable logistic regression analysis.Results: Forty-four patients (16.5%) had advanced fibrosis and 141 patients (53.0%) high activity grade. Prevalence of rs12979860 IL28B genotype was: CC 45.7%, CT 42.7%, and TT 11.6%. Prevalence of advanced fibrosis was lower in those with IL28B CC genotype compared with those without (11.0% vs 21.3%; P = 0.03), with an increasing number of Talleles associated with a higher frequency of advanced fibrosis: CC 11.0%, CT 18.0%, TT33.3% (P = 0.01). Predictors of advanced fibrosis on multivariate analysis were platelet count (odds ratio [OR] 0.98, 95% confidence interval [CI] 0.97–0.99; P < 0.0001), high activity grade (OR 5.68, 95% CI% 1.86–17.32; P = 0.002), IL28B rs12979860 CC genotype(OR 0.36, 95% CI 0.14–0.93; P = 0.03), and aspartate aminotransferase (OR 1.02,95% CI 1.00–1.03; P = 0.046). No association was found between rs8099917 IL28B genotype and liver histology.Conclusions: IL28B rs12979860 CC genotype appears to be independently associated with a lower prevalence of advanced fibrosis stage in HCV-1 infection. This association warrants further evaluation.

Association of IL28B polymorphism with fibrosis, liver inflammation, gender respective natural history of hepatitis C virus in Egyptian patients with genotype 4

The polymorphism of interleukin 28B (IL28B) rs12979860 is associated with spontaneous and treatment-induced clearance in hepatitis C virus (HCV) genotype 4 (G4). However, there is no information on its interaction with gender, moreover its association with intrahepatic inflammation in North Africans is not studied and its association with fibrosis in North Africans (especially Egyptians) is controversial. This study aims to explore the association between the minor allele of the IL28B rs12979860 polymorphism with gender, fibrosis and necroinflammation in Egyptian G4 HCV patients. IL28B rs12979860 was genotyped in 224 individuals, including 100 healthy controls and 124 consecutive patients with chronic HCV. Results showed (1) IL28B rs12979860 minor alleles associated with susceptibity to chronic HCV mainly in men not women, (2) no association between IL28B rs12979860 with fibrosis and necroinflammation activity, (3) the IL28B rs12979860 TT genotype associated with severe fibrosis in women only and with the necroinflammation activity in men using a recessive model. In conclusion, the IL28B rs12979860 polymorphism is not associated with fibrosis and liver inflammation in Egyptian HCV G4. Nonetheless, the TT genotype of IL28B rs12979860 polymorphism affects the natural history of each gender independently.

Impact of Il28b-related single nucleotide polymorphisms on liver transient elastography in chronic hepatitis C infection

BACKGROUND AND AIMS

Recently, several genome-wide association studies have revealed that single nucleotide polymorphisms (SNPs) in proximity to IL28B predict spontaneous clearance of hepatitis C virus (HCV) infection as well as outcome following pegylated interferon and ribavirin therapy among genotype 1 infected patients. Additionally the presence of the otherwise favorable IL28B genetic variants in the context of HCV genotype 3 infection reportedly entail more pronounced liver fibrosis and steatosis. The present study aimed to evaluate the impact of IL28B SNP variability on liver stiffness as accessed by transient elastography.

METHODS

Seven hundred and seventy-one Swedish HCV infected patients sequentially undergoing liver stiffness measurement by means of Fibroscan® in the context of a real-life trial had samples available for IL28B genotyping (rs12979860) and HCV genotyping.

RESULTS

CC(rs12979860) was more common among HCV genotype 2 or 3 infected treatment-naïve patients than among those infected with genotype 1 (P<0.0001). Additionally CC(rs12979860) among HCV genotype 3 infected patients was associated with higher liver stiffness values (P = 0.004), and higher AST to platelet ratio index (APRI; p = 0.02) as compared to carriers of the T allele. Among HCV genotype 1 infected patients, CC(rs12979860) was significantly associated with higher viral load (P = 0.001), with a similar non-significant trend noted among HCV genotype 3 infected patients.

CONCLUSION

This study confirms previous reports that the CC(rs12979860) SNP is associated with more pronounced liver pathology in patients chronically infected with HCV genotype 3 as compared to genotype 1, suggesting that IL28B genetic variants differently regulates the course of HCV infection across HCV genotypes.

Interaction of IFNL3 with insulin resistance, steatosis and lipid metabolism in chronic hepatitis C virus infection

Metabolic changes are inextricably linked to chronic hepatitis C (CHC). Recently polymorphisms in the IFNL3 (IL28B) region have been shown to be strongly associated with spontaneous and treatment induced recovery from hepatitis C virus (HCV) infection. Further, circumstantial evidence suggests a link between IFNL3 single nucleotide polymorphisms and lipid metabolism, steatosis and insulin resistance in CHC. The emerging picture suggests that the responder genotypes of IFNL3 polymorphisms are associated with a higher serum lipid profile, and less frequent steatosis and insulin resistance. This review analyzes the current data regarding this interaction and its meaning for HCV pathogenesis and disease progression.

Association of IL28B genotype with fibrosis progression and clinical outcomes in patients with chronic hepatitis C: a longitudinal analysis

Interleukin (IL)28B polymorphisms are associated with spontaneous clearance of hepatitis C virus (HCV) infection and response to therapy. Whether IL28B genotype affects fibrosis progression or clinical outcome is unclear. Our aim was to study the relationship between IL28B genotype and both histological and clinical outcomes in patients with chronic hepatitis C (CHC). Hepatic fibrosis was scored using the Ishak (0-6) scale; progression was defined as a 2-point increase in Ishak score between biopsies. Multiple logistic and Cox regressions were used to identify variables associated with fibrosis progression. In all, 1,483 patients were included in a baseline cross-sectional analysis, from which 276 were eligible for a paired biopsy analysis (median time between biopsies 4 years), and 400 for a clinical outcome analysis. At baseline biopsy, patients with IL28B CC genotype had significantly higher portal inflammation (2.4 versus 2.2) and alanine aminotransferase (ALT) levels (133 versus 105 U/L; P < 0.05 for all). In the paired biopsy analysis, there was no difference in the frequency of fibrosis progression between patients with IL28B CC and non-CC genotypes (17% versus 23%). In logistic regression, only higher baseline alkaline phosphatase, lower platelets, and greater hepatic steatosis were associated with fibrosis progression. Patients with IL28B CC were twice as likely to develop adverse clinical outcomes compared to non-CC (32% versus 16%; P = 0.007).

CONCLUSION

IL28B CC genotype was associated with greater hepatic necroinflammation, higher ALT, and worse clinical outcomes in CHC patients. This suggests that IL28B CC is associated with a state of enhanced immunity that, on the one hand, can promote viral clearance, but alternately can increase necroinflammation and hepatic decompensation without enhancing fibrosis progression.

Polymorphism Near the Interleukin-28B Gene and Anti-Hepatitis C Viral Response

In a recent genome-wide association study, single nucleotide polymorphisms (SNPs) located near the interleukin-28B gene (IL28B), which encodes type III interferon (IFN) λ3, were shown to be strongly associated with a viral response to pegylated IFNα (PEG-IFNα) and ribavirin (RBV) combination therapy and spontaneous viral clearance in patients chronically and acutely infected with hepatitis C virus (HCV), respectively. The global distribution of allele frequencies shows a remarkable pattern, in which a favorable allele is nearly fixed in East Asia, has an intermediate frequency in Europe, and is least frequent in Africa. Although the underlying mechanisms responsible for viral responses associated with IL28B SNPs have not been completely elucidated, IFN-stimulated gene expression in patients with unfavorable IL28B genotypes tends to be high at baseline and is insufficiently induced by exogenous IFN administration, resulting in poor treatment outcomes. Clinically, triple therapy with PEG-IFNα/RBV together with direct-acting antiviral agents (DAAs) is currently used to treat chronic hepatitis C as a first-line therapy. Although the predictive power of IL28B status may be attenuated, the IL28B genotype will remain relevant to the outcomes of DAA therapy when used in combination with PEG-IFNα as a backbone. Even with the introduction of IFN-free therapies with a new class of highly effective DAAs, IL28B SNPs are still useful predictors of treatment outcomes and can be used to individualize treatment strategies to maximize cost-effectiveness and identify patients at risk of being refractory to treatment. This review summarizes the current understanding of the clinical significance and role of IL28B in HCV infection and response to therapy.

Deep-sequencing analysis of the association between the quasispecies nature of the hepatitis C virus core region and disease progression

Variation of core amino acid (aa) 70 of hepatitis C virus (HCV) has been shown recently to be closely correlated with liver disease progression, suggesting that the core region might be present as a quasispecies during persistent infection and that this quasispecies nature might have an influence on the progression of disease. In our investigation, the subjects were 79 patients infected with HCV genotype 1b (25 with chronic hepatitis [CH], 29 with liver cirrhosis [LC], and 25 with hepatocellular carcinoma [HCC]). Deep sequencing of the HCV core region was carried out on their sera by using a Roche 454 GS Junior pyrosequencer. Based on a plasmid containing a cloned HCV sequence (pCV-J4L6S), the background error rate associated with pyrosequencing, including the PCR procedure, was calculated as 0.092 ± 0.005/base. Deep sequencing of the core region in the clinical samples showed a mixture of "mutant-type" Q/H and "wild-type" R at the core aa 70 position in most cases (71/79 [89.9%]), and the ratio of mutant residues to R in the mixture increased as liver disease advanced to LC and HCC. Meanwhile, phylogenetic analysis of the almost-complete core region revealed that the HCV isolates differed genetically depending on the mutation status at core aa 70. We conclude that the core aa 70 mixture ratio, determined by deep sequencing, reflected the status of liver disease, demonstrating a significant association between core aa 70 and disease progression in CH patients infected with HCV genotype 1b.

Retreatment with peg-interferon and ribavirin in patients with chronic hepatitis C virus genotype 2 or 3 infection with prior relapse

OBJECTIVES

Uncertainty remains regarding the efficacy of retreatment with current standard-of-care peg-interferon (peg-IFN) and ribavirin among patients infected with hepatitis C virus (HCV) genotypes 2 or 3 with relapse after prior therapy.

MATERIALS AND METHODS

Seventy-one patients with chronic HCV genotype 2/3 with prior relapse were enrolled in a phase III multicenter study. Patients were retreated with peg-IFNα-2a 180 μg per week and ribavirin 1000/1200 mg daily. Patients having received previous therapy for 24 weeks were retreated for 48 weeks (Group A), whereas patients having received at least 12 weeks but less than 24 weeks of treatment were allocated to either 48 (Group B) or 24 weeks (Group C) on the basis of whether they had achieved rapid virological response (RVR).

RESULTS

Sustained virological response (SVR) rates of 53%, 81% and 75% were achieved in groups A, B and C, respectively. Patients with favorable baseline characteristics, e.g., less advanced liver fibrosis, age <40 years, duration of infection <20 years, or BMI < 25 kg/m(2), tended to have more favorable outcomes. All patients achieving HCV RNA below 1000 IU/mL day 6 achieved SVR in contrast to none of the patients with detectable HCV RNA at week 12.

CONCLUSIONS

Retreatment with peg-IFN and ribavirin for 24-48 weeks entails SVR among the majority of HCV genotype 2/3 infected patients with prior relapse. However, in light of the prolonged treatment duration, moderate effect and considerable side effects, deterring therapy until new options are available may be preferential, particularly in patients previously treated for 24 weeks.