Impact of IL28B-related single nucleotide polymorphisms on liver histopathology in chronic hepatitis C genotype 2 and 3

Background and Aims

Recently, several genome-wide association studies have revealed that single nucleotide polymorphisms (SNPs) in proximity to IL28B predict spontaneous clearance of HCV infection as well as outcome following peginterferon and ribavirin therapy among HCV genotype 1 infected patients. The present study aimed to evaluate the impact of IL28B SNP variability on liver histology in the context of a phase III treatment trial (NORDynamIC) for treatment-naïve patients with chronic HCV genotype 2 or 3 infection, where pretreatment liver biopsies were mandatory.

Methods

Three hundred and thirty-nine Caucasian patients had samples available for IL28B genotyping (rs12979860) of whom 314 had pretreatment liver biopsies that were evaluated using the Ishak protocol, allowing for detailed grading and staging of liver histopathology.

Results

IL28B CC_rs12979860 genotype in HCV genotype 3 infected patients was associated with higher ALT levels (p<0.0001), higher AST to platelet ratio index (APRI; p = 0.001), and higher baseline viral load (p<0.0001) as compared to patients with the CT or TT genotypes. Additionally the CC_rs12979860 genotype entailed more pronounced portal inflammation (p = 0.02) and steatosis (p = 0.03). None of these associations were noted among HCV genotype 2 infected patients.

Conclusion

This study shows that the CC_rs12979860 SNP is associated with more pronounced liver histopathology in patients chronically infected with HCV genotype 3, which may be secondary to higher viral load. The finding that IL28B variability did not impact on liver pathology or viral load among genotype 2 infected patients implies that IL28B may differentially regulate the course of genotype 2 and 3 infection.     

None of the Six SNPs of IL28B Could Predict Treatment Responses in Genotype 2 Chronic HCV Infected Patients by Propensity Score Matching Analysis

Background & Aims

A combination of pegylated interferon-alpha and ribavirin (PR) is the standard therapy for patients with chronic hepatitis C. The impact of polymorphism of interleukin-28B (IL28B) on sustained virological response (SVR) to PR has been well documented in patients with CHC genotype-1 (GT1), but it is controversial in genotype-2 (GT2) CHC patients. This study investigated the predictability of six single nucleotide polymorphisms (SNP) of IL28B on the treatment responses of PR in patients with CHC GT2.

Method

197 CHC GT2 consecutive patients who received PR treatment in our prospective cohort were enrolled. Hepatitis C virus (HCV) genotyping, quantification of HCV-RNA and genotyping of the ten SNPs of IL28B were performed. Six SNPs of IL28B were chosen for analysis. The propensity score matching (PSM) analysis was applied using patients with CHC GT1 in another prospective cohort as a positive comparison to avoid covariate bias.

Results

The distribution of the six SNPs was similar in GT1 and GT2 patients. Five of these SNPs had strong association with treatment responses in GT1 but not in GT2 patients. After PSM analysis, these five SNPs still showed strong association with rapid virological response (RVR), cEVR and SVR in GT1 and had no influence in GT2 patients. Furthermore, rs12979860 and baseline viral load were the predictors for both RVR and SVR in GT1 patients. However, only baseline viral load could predict RVR and SVR in GT2 patients. In addition, in patients without RVR, rs12979860 was the only predictor for SVR in GT1 but no predictor for SVR was found in GT2.

Conclusions

The genetic polymorphisms of IL28B had no impact on treatment responses in GT2 patients.     

Association between IL28B Polymorphisms and Spontaneous Clearance of Hepatitis B Virus Infection

Background/Aims

Single-nucleotide polymorphisms (SNPs) near the interleukin 28B gene (IL28B; interferon [IFN]-λ-3) are associated with outcomes of chronic hepatitis C virus (HCV) and hepatitis B virus (HBV) infection treated with peginterferon (PEG-IFN) alpha-based antiviral therapy. In this study, we investigated the influence of IL28B polymorphisms on spontaneous clearance of HBV infection in a large Korean cohort.

Methods

Between January 2007 and June 2010, a total of 208 patients with chronic HBV infection and newly diagnosed HBV-related hepatocellular carcinoma were recruited as the CC group [HBsAg(+) for >6 months, anti-HBc(+), and anti-HBs(-)]. In addition, 351 organ donors were stratified into the UE group [n = 106; HBsAg(-), anti-HBc(-), and anti-HBs(-)] or the SC group [n = 245; HBsAg(-), anti-HBc(+), and anti-HBs(+)]. The SNaPshot ddNTP Primer Extension Kit (Applied Biosystems, Foster City, CA) was used for SNP detection. Direct full sequencing of the IL28B coding region was attempted.

Results

Regardless of group, rs12979860 CC was most frequently identified (85.0% in UE, 85.9% in SC, and 93.5% in CC, respectively), whereas rs12979860 TT was not identified in any group. Similarly, rs12980275 AA and rs8099917 TT were most frequently identified (≥85%) regardless of group, whereas rs12980275 GG was identified in only one subject in the SC group. In addition, rs8099917 GG was not identified. The prevalences of CC in rs12979860, AA in rs12980275, and TT in rs8099917 were significantly higher in the CC group when compared with the UE and SC group (all P<0.05). Among 19 novel SNPs in the IL28B coding region, the proportions of 6 SNPs were significantly different among the UE, SC, and CC groups (all P<0.05).

Conclusions

The SNP upstream of IL28B that has the strongest genetic association with HCV recovery has an inverse influence on HBV recovery. Additional studies are needed to understand the mechanisms of this SNP in HBV infection.     

Impact of IL28B,APOH and ITPA Polymorphisms on Efficacy and Safety of TVR- or BOC-Based Triple Therapy in Treatment-Experienced HCV-1 Patients with Compensated Cirrhosis from the ANRS CO20-CUPIC Study

Background

Human genetic factors influence the outcome of pegylated interferon and ribavirin hepatitis C therapy. We explored the role of IL28B, APOH and ITPA SNPs on the outcomes of triple therapy including telaprevir or boceprevir in patients with compensated cirrhosis chronically infected with HCV-1.

Patients and Methods

A total of 256 HCV-1 Caucasian treatment-experienced patients with compensated cirrhosis from the ANRS CO20-CUPIC cohort were genotyped for a total of 10 candidate SNPs in IL28B (rs12979860 and rs368234815), APOH (rs8178822, rs12944940, rs10048158, rs52797880, rs1801689 and rs1801690) and ITPA (rs1127354 and rs7270101). We tested the association of IL28B and APOH SNPs with sustained virological response and of ITPA SNPs with anemia related phenotypes by means of logistic regression assuming an additive genetic model.

Results

None of the six APOH SNPs were associated with sustained virological response. The favorable alleles of the IL28B SNPs rs12979860 and rs368234815 were associated with sustained virological response (rs12979860: OR = 2.35[1.50–3.70], P = 2x10^-4). Refined analysis showed that the effect of IL28B SNPs on sustained virological response was restricted to prior PegIFN/RBV relapse (OR = 3.80[1.82–8.92], P = 8x10^-4). We also confirmed the association between ITPA low activity alleles and protection against early hemoglobin decline in triple therapy (P = 2x10^-5).

Conclusion

Our results suggest that the screening of rs12979860 may remain interesting for decision making in prior relapse HCV-1 Caucasian patients with compensated cirrhosis eligible for a telaprevir- or boceprevir-based therapy.     

Response prediction in chronic hepatitis C by assessment of IP-10 and IL28B-related single nucleotide polymorphisms

Background

High baseline levels of IP-10 predict a slower first phase decline in HCV RNA and a poor outcome following interferon/ribavirin therapy in patients with chronic hepatitis C. Several recent studies report that single nucleotide polymorphisms (SNPs) adjacent to IL28B predict spontaneous resolution of HCV infection and outcome of treatment among HCV genotype 1 infected patients.

Methods and Findings

In the present study, we correlated the occurrence of variants at three such SNPs (rs12979860, rs12980275, and rs8099917) with pretreatment plasma IP-10 and HCV RNA throughout therapy within a phase III treatment trial (HCV-DITTO) involving 253 Caucasian patients. The favorable SNP variants (CC, AA, and TT, respectively) were associated with lower baseline IP-10 (P = 0.02, P = 0.01, P = 0.04) and were less common among HCV genotype 1 infected patients than genotype 2/3 (P<0.0001, P<0.0001, and P = 0.01). Patients carrying favorable SNP genotypes had higher baseline viral load than those carrying unfavorable variants (P = 0.0013, P = 0.029, P = 0.0004 respectively). Among HCV genotype 1 infected carriers of the favorable C, A, or T alleles, IP-10 below 150 pg/mL significantly predicted a more pronounced reduction of HCV RNA from day 0 to 4 (first phase decline), which translated into increased rates of RVR (62%, 53%, and 39%) and SVR (85%, 76%, and 75% respectively) among homozygous carriers with baseline IP-10 below 150 pg/mL. In multivariate analyses of genotype 1-infected patients, baseline IP-10 and C genotype at rs12979860 independently predicted the first phase viral decline and RVR, which in turn independently predicted SVR.

Conclusions

Concomitant assessment of pretreatment IP-10 and IL28B-related SNPs augments the prediction of the first phase decline in HCV RNA, RVR, and final therapeutic outcome.     

Genetic Variation in the Interleukin-28B Gene Is Associated with Spontaneous Clearance and Progression of Hepatitis C Virus in Moroccan Patients

Background

Genetic variation in the IL28B gene has been strongly associated with treatment outcomes, spontaneous clearance and progression of the hepatitis C virus infection (HCV). The aim of the present study was to investigate the role of polymorphisms at this locus with progression and outcome of HCV infection in a Moroccan population.

Methods

We analyzed a cohort of 438 individuals among them 232 patients with persistent HCV infection, of whom 115 patients had mild chronic hepatitis and 117 had advanced liver disease (cirrhosis and hepatocellular carcinoma), 68 individuals who had naturally cleared HCV and 138 healthy subjects. The IL28B SNPs rs12979860 and rs8099917 were genotyped using a TaqMan 5′ allelic discrimination assay.

Results

The protective rs12979860-C and rs8099917-T alleles were more common in subjects with spontaneous clearance (77.9% vs 55.2%; p = 0.00001 and 95.6% vs 83.2%; p = 0.0025, respectively). Individuals with clearance were 4.69 (95% CI, 1.99–11.07) times more likely to have the C/C genotype for rs12979860 polymorphism (p = 0.0017) and 3.55 (95% CI, 0.19–66.89) times more likely to have the T/T genotype at rs8099917. Patients with advanced liver disease carried the rs12979860-T/T genotype more frequently than patients with mild chronic hepatitis C (OR = 1.89; 95% CI, 0.99–3.61; p = 0.0532) and this risk was even more pronounced when we compared them with healthy controls (OR = 4.27; 95% CI, 2.08–8.76; p = 0.0005). The rs8099917-G allele was also associated with advanced liver disease (OR = 2.34; 95% CI, 1.40–3.93; p = 0.0100).

Conclusions

In the Moroccan population, polymorphisms near the IL28B gene play a role both in spontaneous clearance and progression of HCV infection.     

Association of IFNL3 rs12979860 and rs8099917 with Biochemical Predictors of Interferon Responsiveness in Chronic Hepatitis C Virus Infection

Background & Aims

Genetic variations near the interferon lambda 3 gene (IFNL3, IL28B) are the most powerful predictors for sustained virologic response (SVR) in patients with chronic hepatitis C virus (HCV) infection, compared to other biochemical or histological baseline parameters. We evaluated whether the interplay of both IFNL3 polymorphisms rs12979860 and rs8099917 together with non-genetic clinical factors contributes to the predictive role of these genetic variants.

Methods

The cohort comprised 1,402 patients of European descent with chronic HCV type 1 infection. 1,298 patients received interferon-based antiviral therapy, and 719 (55%) achieved SVR. The IFNL3 polymorphisms were genotyped by polymerase chain reaction and melting curve analysis.

Results

A significant correlation was found between the IFNL3 polymorphisms and biochemical as well as virologic predictors of treatment outcome such as ALT, GGT, cholesterol, and HCV RNA levels. In multivariate regression analysis, IFLN3 SNPs, HCV RNA levels, and the GGT/ALT ratio were independent predictors of SVR. Dependent on the GGT/ALT ratio and on the HCV RNA concentration, significant variations in the likelihood for achieving SVR were observed in both, carriers of the responder as well as non-responder alleles.

Conclusions

Our data support a clear association between IFNL3 genotypes and baseline parameters known to impact interferon responsiveness. Improved treatment outcome prediction was achieved when these predictors were considered in combination with the IFNL3 genotype.     

Characterization of serum proteins associated with IL28B genotype among patients with chronic hepatitis C

Introduction

Polymorphisms near the IL28B gene (e.g. rs12979860) encoding interferon λ3 have recently been associated with both spontaneous clearance and treatment response to pegIFN/RBV in chronic hepatitis C (CHC) patients. The molecular consequences of this genetic variation are unknown. To gain further insight into IL28B function we assessed the association of rs12979860 with expression of protein quantitative traits (pQTL analysis) generated using open-platform proteomics in serum from patients.

Methods

41 patients with genotype 1 chronic hepatitis C infection from the Duke Liver Clinic were genotyped for rs12979860. Proteomic profiles were generated by LC-MS/MS analysis following immunodepletion of serum with MARS14 columns and trypsin-digestion. Next, a latent factor model was used to classify peptides into metaproteins based on co-expression and using only those peptides with protein identifications. Metaproteins were then analyzed for association with IL28B genotype using one-way analysis of variance.

Results

There were a total of 4,186 peptides in the data set with positive identifications. These were matched with 253 proteins of which 110 had two or more associated, identified peptides. The IL28B treatment response genotype (rs12979860_CC) was significantly associated with lower serum levels of corticosteroid binding globulin (CBG; p = 9.2×10⁻⁶), a major transport protein for glucocorticoids and progestins. Moreover, the CBG metaprotein was associated with treatment response (p = 0.0148), but this association was attenuated when both IL28B genotype and CBG were included in the model, suggesting that the CBG association may be independent of treatment response.

Conclusions

In this cohort of chronic hepatitis C patients, IL28B polymorphism was associated with serum levels of corticosteroid binding globulin, a major transporter of cortisol, however, CBG does not appear to mediate the association of IL28B with treatment response. Further investigation of this pathway is warranted to determine if it plays a role in other comorbidities of HCV-infection.     

IL28B, HLA-C, and KIR variants additively predict response to therapy in chronic hepatitis C virus infection in a European Cohort: a cross-sectional study

Background

To date, drug response genes have not proved as useful in clinical practice as was anticipated at the start of the genomic era. An exception is in the treatment of chronic hepatitis C virus (HCV) genotype 1 infection with pegylated interferon-alpha and ribavirin (PegIFN/R). Viral clearance is achieved in 40%–50% of patients. Interleukin 28B (IL28B) genotype predicts treatment-induced and spontaneous clearance. To improve the predictive value of this genotype, we studied the combined effect of variants of IL28B with human leukocyte antigen C (HLA-C), and its ligands the killer immunoglobulin-like receptors (KIR), which have previously been implicated in HCV viral control.

Methods and Findings

We genotyped chronic hepatitis C (CHC) genotype 1 patients with PegIFN/R treatment-induced clearance (n = 417) and treatment failure (n = 493), and 234 individuals with spontaneous clearance, for HLA-C C1 versus C2, presence of inhibitory and activating KIR genes, and two IL28B SNPs, rs8099917 and rs12979860. All individuals were Europeans or of European descent. IL28B SNP rs8099917 “G” was associated with absence of treatment-induced clearance (odds ratio [OR] 2.19, p = 1.27×10⁻⁸, 1.67–2.88) and absence of spontaneous clearance (OR 3.83, p = 1.71×10⁻¹⁴, 2.67–5.48) of HCV, as was rs12979860, with slightly lower ORs. The HLA-C C2C2 genotype was also over-represented in patients who failed treatment (OR 1.52, p = 0.024, 1.05–2.20), but was not associated with spontaneous clearance. Prediction of treatment failure improved from 66% with IL28B to 80% using both genes in this cohort (OR 3.78, p = 8.83×10⁻⁶, 2.03–7.04). There was evidence that KIR2DL3 and KIR2DS2 carriage also altered HCV treatment response in combination with HLA-C and IL28B.

Conclusions

Genotyping for IL28B, HLA-C, and KIR genes improves prediction of HCV treatment response. These findings support a role for natural killer (NK) cell activation in PegIFN/R treatment-induced clearance, partially mediated by IL28B. Please see later in the article for the Editors'' Summary     

An IL28B genotype-based clinical prediction model for treatment of chronic hepatitis C

Background

Genetic variation in IL28B and other factors are associated with sustained virological response (SVR) after pegylated-interferon/ribavirin treatment for chronic hepatitis C (CHC). Using data from the HALT-C Trial, we developed a model to predict a patient''s probability of SVR based on IL28B genotype and clinical variables.

Methods

HALT-C enrolled patients with advanced CHC who had failed previous interferon-based treatment. Subjects were re-treated with pegylated-interferon/ribavirin during trial lead-in. We used step-wise logistic regression to calculate adjusted odds ratios (aOR) and create the predictive model. Leave-one-out cross-validation was used to predict a priori probabilities of SVR and determine area under the receiver operator characteristics curve (AUC).

Results

Among 646 HCV genotype 1-infected European American patients, 14.2% achieved SVR. IL28B rs12979860-CC genotype was the strongest predictor of SVR (aOR, 7.56; p<.0001); the model also included HCV RNA (log10 IU/ml), AST∶ALT ratio, Ishak fibrosis score and prior ribavirin treatment. For this model AUC was 78.5%, compared to 73.0% for a model restricted to the four clinical predictors and 60.0% for a model restricted to IL28B genotype (p<0.001). Subjects with a predicted probability of SVR <10% had an observed SVR rate of 3.8%; subjects with a predicted probability >10% (43.3% of subjects) had an SVR rate of 27.9% and accounted for 84.8% of subjects actually achieving SVR. To verify that consideration of both IL28B genotype and clinical variables is required for treatment decisions, we calculated AUC values from published data for the IDEAL Study.

Conclusion

A clinical prediction model based on IL28B genotype and clinical variables can yield useful individualized predictions of the probability of treatment success that could increase SVR rates and decrease the frequency of futile treatment among patients with CHC.     

Predictive Value of Interferon-Lambda Gene Polymorphisms for Treatment Response in Chronic Hepatitis C

Background

IL28B gene polymorphism is the best baseline predictor of response to interferon alfa-based antiviral therapies in chronic hepatitis C. Recently, a new IFN-L4 polymorphism was identified as first potential functional variant for induction of IL28B expression. Individualization of interferon alfa-based therapies based on a combination of IL28B/IFN-L4 polymorphisms may help to optimize virologic outcome and economic resources.

Methods

Optimization of treatment outcome prediction was assessed by combination of different IL28B and IFN-L4 polymorphisms in patients with chronic HCV genotype 1 (n = 385), 2/3 (n = 267), and 4 (n = 220) infection treated with pegylated interferon alfa (PEG-IFN) and ribavirin with (n = 79) or without telaprevir. Healthy people from Germany (n = 283) and Egypt (n = 96) served as controls.

Results

Frequencies of beneficial IL28B rs12979860 C/C genotypes were lower in HCV genotype 1/4 infected patients in comparison to controls (20–35% vs. 46–47%) this was also true for ss469415590 TT/TT (20–35% vs. 45–47%). Single interferon-lambda SNPs (rs12979860, rs8099917, ss469415590) correlated with sustained virologic response (SVR) in genotype 1, 3, and 4 infected patients while no association was observed for genotype 2. Interestingly, in genotype 3 infected patients, best SVR prediction was based on IFN-L4 genotype. Prediction of SVR with high accuracy (71–96%) was possible in genotype 1, 2, 3 and 4 infected patients who received PEG-IFN/ribavirin combination therapy by selection of beneficial IL28B rs12979860 C/C and/or ss469415590 TT/TT genotypes (p<0.001). For triple therapy with first generation protease inhibitors (PIs) (boceprevir, telaprevir) prediction of high SVR (90%) rates was based on the presence of at least one beneficial genotype of the 3 IFN-lambda SNPs.

Conclusion

IFN-L4 seems to be the best single predictor of SVR in genotype 3 infected patients. For optimized prediction of SVR by treatment with dual combination or first generation PI triple therapies, grouping of interferon-lambda haplotypes may be helpful with positive predictive values of 71–96%.     

Test of IL28B Polymorphisms in Chronic Hepatitis C Patients Treated with PegIFN and Ribavirin Depends on HCV Genotypes: Results from a Meta-Analysis

Background

Many studies have been published on the association between single nucleotide polymorphisms (SNP) near the IL28B gene and response to the combined treatments of pegylated-interferon (PegIFN) and ribavirin (RBV) in chronic HCV-infected patients, but without identical conclusions. The aim of this study was to assess impact of the IL28B polymorphisms on the effect of HCV standard treatment using meta-analysis based method.

Methods

Association studies between polymorphisms of rs12979860 or rs8099917 and response to PegIFN/RBV treatment in chronic HCV patients were retrieved from PubMed. Data of qualified studies on sustained virological response (SVR) in different genotypes were extracted and analyzed using meta-analysis method in Stata 10 software.

Results

Thirty-four papers, containing 46 independent studies, were included in the analysis. In the HCV G1/4 patients without treatment history, individuals carrying rs12979860 CC genotype were more likely to achieve SVR (OR 3.97, 95%CI 3.29–4.80) compared to those carrying CT/TT genotypes. Similar results were observed in the HCV G1/4 patients with unsuccessful or unknown treatment history (OR 3.76, 95%CI 2.67–5.28) or in the patients co-infected with human immunodeficiency virus (OR 5.20, 95%CI 3.04–8.90). However, associations could not be observed in HCV G2/3 patients. For rs8099917, similar results were obtained for genotype TT compared to genotypes TG/GG, indicating that TT genotype was significantly associated with better treatment response in patients infected with genotype 1 or 4 HCV, but not genotype 2 or 3 HCV.

Conclusion

Polymorphisms of rs12979860 and rs8099917 near IL28B only associate with the treatment response to PegIFN/RBV in patients infected with HCV genotype 1 or 4 but not with genotype 2 or 3, irrespective of the previous treatment history or HIV co-infected status. Therefore, identification of IL28B genotypes is necessary only in patients infected with relatively difficult-to-treat genotype 1 or 4 HCV.     

IL28B Gene Polymorphisms and US Liver Fatty Changes in Patients Who Spontaneously Cleared Hepatitis C Virus Infection

Background

Recent clinical studies have shown that the presence of CC genotype in the rs12979860 region of IL28B gene is associated with an increase in the probability of spontaneous clearance of hepatitis C virus (HCV). Moreover, IL28B polymorphism seems to influence the probability of developing liver steatosis in chronic HCV patients.

Aims

The aims of our clinical study were 1) to verify the distribution of IL28B genotypes (CC, CT or TT) among subjects with spontaneous clearance of HCV infection and 2) to examine the correlation between IL28B polymorphism and hepatic steatosis among these subjects.

Methods and patients

We enrolled 41 subjects with spontaneous resolution of HCV infection (detectable serum anti-HCV but undetectable HCV-RNA) and 134 healthy controls from the same geographical area. The IL28B single-nucleotide polymorphism (SNP) rs12979860 was genotyped by using a Pyrosequencing™ technique. The presence of steatosis was assessed by liver biopsy or ultrasound examination in the 41 study subjects.

Results

CC, CT and TT-genotypes of the SNP rs1979860 were found in 66%, 24% and 10% of the subjects who spontaneously cleared HCV and in 31%, 54% and 15% of controls, respectively (p = 0.0003). Among the study subjects, females with CC-genotype were significantly more represented (p = 0.02). Hepatic steatosis did not correlate with IL28B genotype (p = 0,14) but only with a high body mass index (BMI) value (p = 0.03).

Conclusions

Female subjects carrying IL28B CC-genotype are significantly more represented among Italian patients who spontaneously cleared HCV infection. In addition, among these subjects, the presence of liver steatosis does not correlate with IL28B genotype but is solely related to the occurrence of high BMI. Thus, the association between IL28B polymorphism and steatosis in chronic HCV patients requires the presence of active HCV replication to occur, while in subjects who have cleared the infection, the mechanism(s) inducing liver steatosis are independent from IL28B profile.     

Female sex and IL28B, a synergism for spontaneous viral clearance in hepatitis C virus (HCV) seroconverters from a community-based cohort

Background & Aims

Since acute hepatitis C virus (HCV) infection is often asymptomatic, it is difficult to examine the rate and determinants of spontaneous clearance. Consequently, these studies are subject to bias, which can potentially lead to biased rates of viral clearance and risk estimates. We evaluated determinants of spontaneous HCV clearance among HCV seroconverters identified in a unique community-based cohort.

Methods

Subjects were 106 drug users with documented dates of HCV seroconversion from the Amsterdam Cohort Study. Logistic regression was used to examine sociodemographic, behavioral, clinical, viral and host determinants, measured around acute infection, of HCV clearance.

Results

The spontaneous viral clearance rate was 33.0% (95% confidence interval (CI) 24.2–42.8). In univariate analyses female sex and fever were significantly associated with spontaneous clearance. The favorable genotypes for rs12979860 (CC) and rs8099917 (TT) were associated with spontaneous clearance, although borderline significant. In multivariate analysis, females with the favorable genotype for rs12979860 (CC) had an increased odds to spontaneously clear HCV infection (adjustedOR 6.62, 95% 2.69–26.13), whereas females with the unfavorable genotype were as likely as men with the favorable and unfavorable genotype to clear HCV. Chronic Hepatitis B infection and absence of HIV coinfection around HCV seroconversion also favor HCV clearance.

Conclusions

This study shows that co-infection with HIV and HBV and genetic variation in the IL28B region play an important role in spontaneous clearance of HCV. Our findings suggest a possible synergistic interaction between female sex and IL28B in spontaneous clearance of HCV.     

IL28B SNP rs12979860 is a critical predictor for on-treatment and sustained virologic response in patients with hepatitis C virus genotype-1 infection

Background

Single nucleotide polymorphisms (SNPs) of interleukin-28B (IL28B) have received considerable interest for their association with sustained virological response (SVR) when treating patients of genotype-1 hepatitis C virus (GT1-HCV) chronic infection with pegylated interferon and ribavirin (PegIFN/RBV). This study was to investigate the predictive power of IL28B SNPs for on-treatment responses and SVR in treatment-naïve patients with GT1-HCV chronic infection.

Methodology/Principal Findings

We analyzed ten SNPs of IL28B in 191 treatment-naïve patients with GT1-HCV chronic infection who received PegIFN/RBV. In these patients, rapid virological response (RVR), early virological response (EVR) and SVR were achieved in 69.6%, 95.8% and 68.6% of the patients, respectively. Multivariate analysis (odds ratio; 95% confidence interval; P value) indicated age (0.96; 0.93–0.99; 0.012), low baseline viral load (4.65; 2.23–9.66; <0.001) and CC genotype of rs12979860 (7.74; 2.55–23.53; <0.001) but no other SNPs were independent predictors for SVR. In addition, none of the ten SNPs examined were associated with baseline viral load and stages of liver fibrosis. Regarding RVR, low baseline viral load (2.83; 1.40–5.73; 0.004) and CC genotype of rs12979860 (10.52; 3.45–32.04; <0.001) were two critical predictors. As for EVR, only CC genotype of rs12979860 (36.21; 6.68–196.38; <0.001) was the predictor. Similarly, for end of treatment response (ETR), CC genotype of rs12979860 (15.42; 4.62–51.18; <0.001) was the only predictor. For patients with RVR, only low baseline viral load (3.90; 1.57–9.68; 0.003) could predict the SVR. For patients without RVR, only rs12979860 (4.60; 1.13–18.65; 0.033) was the predictor for SVR.

Conclusions/Significance

rs12979860 is the critical predictor for RVR, EVR, ETR and SVR in treatment-naïve patients of GT1-HCV chronic infection. Furthermore, this SNP is the only predictor for SVR in patients without RVR. These results have provided evidence that rs12979860 is the ideal IL28B SNP for genetic testing in treating patients of GT1-HCV chronic infection.     

IL28B Polymorphism Correlates with Active Hepatitis in Patients with HBeAg-Negative Chronic Hepatitis B

Background & Aims

The clinical relevance of single nucleotide polymorphisms (SNPs) near the IL28B gene is controversial in patients with hepatitis B virus (HBV) infection. This study aimed to investigate the role of viral and host factors, including IL28B genotypes, in the natural course of chronic hepatitis B (CHB).

Methods

The study enrolled consecutive 115 treatment-naive CHB patients. HBV viral loads, genotypes, precore and basal core promotor mutations, serum hepatitis B surface antigen (HBsAg) and interferon-gamma inducible protein 10 (IP-10) levels as well as four SNPs of IL28B were determined. Serial alanine transaminase (ALT) levels in the previous one year before enrollment at an interval of three months were recorded. Factors associated with active hepatitis, defined as persistent ALT >2× upper limit of normal (ULN) or a peak ALT level >5× ULN, were evaluated.

Results

The prevalence of rs8105790 TT, rs12979860 CC, rs8099917 TT, and rs10853728 CC genotypes were 88.3%, 87.4%, 88.4% and 70.9%, respectively. In HBeAg-positive patients (n = 48), HBV viral load correlated with active hepatitis, while in HBeAg-negative patients (n = 67), rs10853728 CC genotype (p = 0.032) and a trend of higher IP-10 levels (p = 0.092) were associated with active hepatitis. In multivariate analysis, high viral load (HBV DNA >10⁸ IU/mL, p = 0.042, odds ratio = 3.946) was significantly associated with HBeAg-positive hepatitis, whereas rs10853728 CC genotype (p = 0.019, odds ratio = 3.927) was the only independent factor associated with active hepatitis in HBeAg-negative population.

Conclusions

HBV viral load and IL28B rs10853728 CC genotype correlated with hepatitis activity in HBeAg-positive and HBeAg-negative CHB, respectively. Both viral and host factors play roles in disease activity during different phases of CHB.     

Association Analysis between SNPs in IL-28B Gene and the Progress of Hepatitis B Infection in Han Chinese

Objective

As a candidate gene association study, we investigated the genetic association of SNPs in IL-28B genes with different outcomes of HBV infection, including LC and HCC occurrence.

Methods

Chinese Han subjects were categorized into two groups: 406 LC caused by CHB and 406 HCC caused by CHB. Genomic DNA was isolated from whole blood samples, SNPs were detected using high resolution melting curve (HRM) method. PCR amplification was carried out under the same conditions in a 96-well plate in Real-Time PCR System. Then 341 LC and 356 HCC patients caused by HBV infection were analyzed as a verification by independent sample. 393 CHB patients and 244 health subjects were included as control.

Results

CHB patients who progress to LC or HCC showed a significant different frequency in rs12979860 (p = 0.046). Patients with HCC carried more frequently the T alleles in rs12979860 comparison to LC. Same results were found in the independent sample.

Conclusion

IL-28B rs12979860 C/T polymorphism T allele appears to be more prevalent in patients with HCC than in LC. Carriage of this allele seems to enhance the risk for developing HCC. Gene polymorphism of IL-28B may confer symptomatic specificity in progress and extent of hepatitis B infection.     

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.     

Association of IL12B polymorphisms with susceptibility to Graves ophthalmopathy in a Taiwan Chinese population

Background

Interleukin 12B (IL12B) gene polymorphisms have been linked to several inflammatory diseases, but their role in the development of Graves ophthalmopathy (GO) in Graves disease (GD) patients is unclear. The purpose of this study was to investigate the disease association of IL12B single nucleotide polymorphisms (SNPs).

Methods

A Taiwan Chinese population comprising 200 GD patients with GO and 271 GD patients without GO was genotyped using an allele-specific extension and ligation method. Hardy-Weinberg equilibrium was estimated using the chi-square test. Allele and genotype frequencies were compared between GD patients with and without GO using the chi-square test.

Results

The genotype and allele frequencies of examined SNPs did not differ between GD patients with and without GO. Although the genotype distribution remained nonsignificant in the sex-stratified analyses, the frequency of the T allele at SNP rs1003199 was significantly higher in patients with GO in the male cohort (P = 6.00 × 10^-3). In addition, haplotypes of IL12B may be used to predict the risk of GO (P = 1.70 × 10^-2); however, we could not prove the statistical significance of analysis after applying the Bonferroni correction.

Conclusions

Our results provide new information that the examined IL12B gene polymorphisms may be associated with susceptibility to GO in the Taiwan Chinese population in a sex-specific manner. This conclusion requires further investigation.