Interleukin 28B-related polymorphisms: a pathway for understanding hepatitis C virus infection?
ABSTRACT: AIM:To analyze the role of rs12979860 and rs8099917 polymorphisms in hepatitis C virus (HCV) genotype 1 infection of Brazilians. METHODS:A total of 145 adult patients diagnosed with genotype 1 chronic hepatitis C (CHC) who had completed a 48-wk regimen of pegylated-interferon α-2a or -2b plus ribavirin combination therapy were recruited from six large urban healthcare centers and 199 healthy blood donors (controls) from a single site between January 2010 and January 2012. Data on the patients' response to treatment was collected. Polymerase chain reaction-restriction fragment length polymorphism genotyping of the interleukin (IL)28B gene fragment encompassing the single nucleotide polymorphisms (SNPs) rs12979860 (C/T) and rs8099917 (T/G) was carried out for 79 of the CHC patients and 199 of the controls. Bi-directional amplicon sequencing of the two SNPs was carried out for the remaining 66 CHC patients. RESULTS:SNP rs12979860 genotyping was successful in 99.5% of the controls and 97.2% of the CHC patients, whereas the SNP rs8099917 genotyping was successful in 95.5% of the controls and 100% of the CHC patients. The genotype and allele distributions for both rs12979860 and rs8099917 were significantly different between the control and CHC patient groups, with significantly higher genotype frequencies of CC and TT in the controls (P = 0.037 and 0.046, respectively) and of TT and GG in the CHC patients (P = 0.0009 and 0.0001, respectively). Analysis of the CHC patients who achieved sustained virological response (SVR) to treatment (n = 55) indicated that the rs12979860 C allele and CC genotype were predictors of SVR (P = 0.02). No significant correlation was found between rs8099917 genotypes and treatment response, but carriers of the T allele showed significantly higher rates of SVR (P = 0.02). Linkage disequilibrium analysis of the group that achieved SVR showed a significant association between rs12979860 and rs8099917 (P = 0.07). CONCLUSION:The higher allele frequency of rs12979860 C and rs8099917 T observed in non-HCV-infected individuals may indicate a potential protective role for these IL28B-related polymorphisms.
Project description:AIM:To evaluate the association of IFNL3 (IL28B) SNP rs4803217 with severity of disease and treatment outcome in chronic hepatitis C (CHC). METHODS:The study enrolled 196 CHC Polish patients (82 women and 114 men in age 20-64) infected with hepatitis C virus (HCV) genotype 1. They were treatment naïve and qualified to pegylated interferon alpha (PEG-IFN-?) and ribavirin (RBV) therapy. The analyzed baseline parameters included: degree of inflammation, stage of fibrosis, viral load as well as alanine aminotransferase (ALT), asparagine aminotransferase (AST) and total bilirubin (TBIL). The analysis of response to therapy included: sustained virological response (SVR), defined as undetectable serum HCV RNA level six month after completion of 48-wk therapy, and relapse, defined as achieving undetectable viral load at the end of treatment but not SVR. HCV genotyping and HCV RNA quantification were performed using commercially available tests. DNA was isolated from peripheral blood mononuclear cells or from buccal cell swabs. In addition to rs4803217, also single nucleotide polymorphisms (SNPs) (rs12979860, rs8099917 and rs12980275) of known significance in predicting of HCV clearance were analyzed. SNPs were determined by high resolution melt analysis and confirmed by sequencing of amplicons. RESULTS:Frequency of rs4803217 genotypes in studied group was as follows: 27.55%; 54.59% and 17.86% for CC, CA and AA, respectively. The rs4803217 SNP, similar to other analyzed SNPs, was not associated with severity of CHC (grade of inflammation, stage of fibrosis, baseline viral load as well as biochemical parameters: ALT, AST, TBIL). It was demonstrated that the rs4803217C allele is associated with SVR (C vs A: P < 0.0001; dose of C allele: P = 0.0002) and non-relapse (C vs A: P = 0.001; dose of C allele: P = 0.002). Moreover, it was found that patients with CC genotype have significantly higher response rates as compared with CA/AA patients (P < 0.0001), whereas patients carrying A allele are significantly predisposed to relapse after treatment (P = 0.0007). Moreover, the association of rs4803217 with SVR was comparable to that of rs12979860 and stronger as observed for rs12980275 and rs8099917. Association of rs4803217 with relapse, was the strongest as compared with the other SNPs. The analysis of combined rs4803217 and rs8099917 genotypes demonstrated that additional genotyping of rs8099917 had no significant impact on the prediction of SVR. Multivariate analysis revealed that among analyzed SNPs only rs4803217 is an independent predictor of SVR (P = 0.016) and relapse (P = 0.024). CONCLUSION:The rs4803217 SNP is a strong, independent and superior predictor of SVR and relapse in HCV genotype 1 infected CHC patients treated with PEG-IFN-? and RBV.
Project description:BACKGROUND:The aim of this study was to determine whether two polymorphisms of the human interferon lambda 4 (IFNL4) gene (rs12979860 and rs8099917) can predict sustained virologic response (SVR) following antiviral therapy in patients with inherited bleeding disorder and chronic hepatitis C (CHC). METHODS:This retrospective study was conducted on 294 patients with congenital bleeding disorder and CHC who were treated with Peg-Interferon-? (PegIFN) and Ribavirin (RBV). Baseline patient and viral parameters were measured and analyzed statistically to assess their combined and individual contributions to SVR prediction. RESULTS:The most prevalent variants of rs12979860 and rs8099917 identified among the study patients were CT (45.9%) and TT (57.6%), respectively. Overall, SVR was achieved in 69% of the study patients. The rate of SVR was lower in patients with HCV genotype-1 than in those with HCV genotype-3 (62% vs 88%; P<.001; OR=0.23). Multivariate analysis of SVR predictors in patients with HCV genotype-1 infection included age (<24 years), BMI (<25), absence of cirrhosis, HCV RNA level (<400 000 IU/mL), rs8099917 TT and rs12979860 CC, all of which were associated with a higher SVR rate. In HCV genotype-3 infection, only rs12979860 CC was significantly associated with SVR. CONCLUSION:These results demonstrate that polymorphisms of the IFNL4 gene are highly associated with SVR to PegIFN and RBV combination therapy in patients with a congenital bleeding disorder and CHC. Assessment of rs12979860 and rs8099917 genotypes can guide physicians in choosing an optimal treatment regimen, including less expensive therapies that may only be available in many geographic locales.
Project description:BACKGROUND:A dinucleotide variant rs368234815 in interferon lambda 4 (IFNL4) gene was recently found to be associated with the hepatitis C virus (HCV) treatment response. This study aimed to assess the impact of IFNL4 rs368234815 polymorphism on treatment response to pegylated-IFN alpha (Peg-IFN-?) and ribavirin (RBV) in hemophilic patients with chronic hepatitis C (CHC). MATERIALS AND METHODS:In this retrospective study, 92 hemophilic patients with CHC who were treated with Peg-IFN-?/RBV were investigated. Single-nucleotide polymorphisms (SNPs) in IFNL genomic region including rs368234815, rs12979860, and rs8099917 were analyzed by DNA sequencing. RESULTS:Of the 92 patients, 63 (68.5%) achieved sustained virological response (SVR). Of the 43 patients with rs368234815 TT/TT genotype, 36 (83.7%) achieved SVR, while in 49 patients with non-TT/TT genotypes, 27 (55.1%) achieved SVR. Other pretreatment parameters predicted SVR were patients' body mass index, HCV genotype, rs12979860, and rs8099917 SNPs. In multivariate analysis, all above-mentioned parameters except rs8099917 remained as predictors of SVR. IFNL4 rs368234815 was a strong predictor of SVR; however, the prediction power of this SNP was the same as that of rs12979860 SNP in the patients of the current study. CONCLUSION:IFNL4 rs368234815 SNP can be considered for decision-making in the treatment of HCV-infected patients.
Project description:The strong impact of interleukin 28B (IL28B) polymorphisms on sustained virological response (SVR) after peginterferon and ribavirin treatment in patients with chronic hepatitis C (CHC) is well-known. We investigated IL28B variability and hepatic expression of IP10, IFI27, ISG15, and MX1 in CHC patients, the relation of each with their clinical characteristics, and how they associated with responses to combined therapy. Genotyping and gene expression analysis were conducted in a selected cohort of treatment-naïve patients who underwent interferon and ribavirin treatment. Differential expression of IP10, IFI27, ISG15, and MX1 genes was assessed from pretreatment liver biopsies using quantitative PCR. Histopathological evaluation of liver specimens was performed on the basis of the Scheuer's modified scale. We showed that hepatic IFI27, ISG15, and MX1 expression was lower in the IL28B CC 12979860 and TT rs8099917 groups than in the CT-TT rs12979860 and TG-GG rs8099917 groups (P < 0.001). We found no differences in IP10 expression between the IL28B genotypes (P > 0.05); in contrast, IP10 expression was significantly affected by the progression of fibrosis (P = 0.007). We showed that the rs12979860 CC genotype was associated with successful treatment when compared to the rs12979860 CT-TT genotype (P = 0.004). Additionally, the expression levels of IP10, IFI27 and ISG15, but not MX1, were significantly higher in non-SVR patients than in SVR patients. The effect of variation in IL28B on the results of IFN-based treatment may be associated with changes in IFI27 and ISG15, but not with IP10. Silencing of IP10 is positive and independent from IL28B prediction of SVR, which is strongly associated with liver fibrosis in CHC patients.
Project description:INTRODUCTION: Single-nucleotide polymorphisms (SNPs) associated with hepatitis C virus (HCV) clearance were identified near the IL28B gene. Coinfection by the human immunodeficiency virus (HIV) influences the course of HCV contributing to liver damage. Nevertheless, little is known about the relationship between these SNPs and HCV/HIV coinfection. Our aim was to estimate the frequencies of the allelic and genotypic variants of the IL28B polymorphisms rs12979860 (C/T) and rs8099917 (T/G) and their possible association with the establishment of HCV infection. METHODOLOGY: A total of 199 non-infected controls and 230 patients with chronic hepatitis C, including 53 coinfected with HIV, participated in the study. Genotyping consisted of polymerase chain reaction and subsequent analysis of the restriction patterns resulting from exposure to endonucleases. RESULTS: Among the controls with established results, 47.4% (90/190) exhibited the rs12979860 CC genotype, 43.7 CT, and 8.9% TT, whereas 29.1% (66/227), 51.5%, and 19.4% of the patients exhibited the CC, CT, and TT genotypes, respectively. With respect to rs8099917, 66.8% (133/199) of the controls exhibited the TT genotype, 31.2% TG, and 2.0% GG, whereas 56.1% (129/230), 40.9%, and 3.0% of the patients exhibited the TT, TG, and GG genotypes, respectively. CONCLUSION: The frequencies of the rs12979860 C allele and CC genotype and of the rs8099917 T allele and TT genotype were significantly higher among controls compared with patients, thus confirming the suggested protective effect against HCV infection. No significant difference was observed in the genotype and allelic distributions between the mono- and coinfected patients.
Project description:Type III interferon (IFNs) encoded by IFN lambda (IFNL) genes induce antiviral activity. The IFNL clusters include IFNL1/IL29, IFNL2/IL28A, IFNL3/IL28B and IFNL4 genes. The single nucleotide polymorphisms (SNPs, rs12979860 and rs8099917) associated with virological responses against hepatitis C virus (HCV) infections are recently mapped to IFNL4 gene. The IFNL gene polymorphisms also plays role in immune clearance, inflammation and risk of developing hepatocellular carcinoma. There is significant genetic heterogeneity of IFNL4 polymorphisms among ethnic populations that need to be regionally studied for viral infection, treatment response and relapse. The IFNL4 risk allele, genotype and haplotype frequencies across north Indian cohort were determined among chronic hepatitis C (CHC) cases (n?=?141) and healthy controls (n?=?111) by allele specific real-time PCR. Odds ratio was calculated for HCV exposure and treatment response using dominant and minor allele/genotype as reference. Non-random associations of these two SNP loci were evaluated by linkage disequilibrium plot. The minor allele (T) frequency of rs12979860C/T is 0.241 and 0.229; and minor allele (G) frequency for SNP rs8099917T/G is 0.174 and 0.171 among CHC cases and healthy control respectively. Coefficient of linkage disequilibrium (D') of these two SNPs is very high (D'?=?0.98, r2?>?0.6) in CHC group than in healthy control (D'?=?0.76, r2?=?0.39) which indicate that both SNPs are strongly linked in CHC population than healthy control. Favorable association of IFNL4 haplotype (C-T), genotype (CC for rs12979860 and TT for rs8099917) with anti HCV therapy were found significant (p?=?0.009, 0.021 and 0.001) for SVR. Favorable genotypes are also found to be predominant across the Indian study population.
Project description:BACKGROUND:SNPs near the interferon lambda (IFNL) 3 gene are predictors for sustained virological response (SVR) in patients with chronic hepatitis C genotype (GT) 1. In addition, a dinucleotide frame shift in ss469415590 was described, which generates IFNL4. In this study, we compared the role of IFNL4 variants with IFNL3-(rs12979860) and IFNL3-(rs8099917) on response to pegylated (PEG)-IFN and Ribavirin (RBV) in patients with chronic hepatitis C GT2/3. METHODS:We recruited 1006 patients with chronic hepatitis C and GT2/3 in a large German registry. A treatment with PEG-IFN and Ribavirin was started by 959 patients. We performed genotyping of IFNL3 (rs12979860, n = 726; rs8099917, n = 687) and of IFNL4 (ss469415590; n = 631). RESULTS:Both preferable IFNL3 genotypes were associated with RVR (both p<0.0001) rather than with SVR (rs12979860: p = 0.251; rs8099917: p = 0.447). Only RVR was linked to SVR in univariate and multivariate analyzes (both p<0.001). Concordance of genotyping in patients with available serum samples and EDTA blood samples (n = 259) was more than 96% for both IFNL3 SNPs. IFNL3-(rs12979860) correlated with IFNL4: 99.2% of patients with IFNL3-(rs12979860)-CC were IFNL4-(ss469415590)-TT/TT. IFNL3-(rs12979860)-CT was linked with IFNL4-(ss469415590)-TT/?G (98.0%) and IFNL3-(rs12979860)-TT was associated with IFNL4-(ss469415590)-?G/?G (97.6%). CONCLUSION:IFNL3 genotyping from serum was highly efficient and can be used as an alternative if EDTA whole blood is not available. In Caucasian GT2/3 patients genotyping for INFL4-(ss469415590) does not lead to additional information for the decision-making process. Importantly, IFNL3 SNPs were not associated with SVR but with RVR. Even in the era of new direct acting antiviral (DAA) therapies, IFNL3 testing may therefore still be considered for naïve GT2/3 patients to decide if dual Peg-IFN/RBV therapy is an option in resource limited regions.
Project description:AIM:The purpose of this study was to compare the distribution of interleukin (IL)-28B genotypes between Iranian healthy individuals and patients with chronic hepatitis C based on the genotype. BACKGROUND:Polymorphisms in the region of IL-28B gene have been identified as the strongest genetic pretreatment predictor of sustained virological response (SVR) in hepatitis C infection. PATIENTS AND METHODS:In this study, 147 patients with chronic hepatitis C and 80 healthy individuals were included. The IL-28B rs12979860 and rs8099917 polymorphisms were genotyped by PCR-RFLP method and the frequency of IL-28B polymorphisms with respect to HCV genotypes was also determined. RESULTS:The frequencies of rs12979860 TT, CC and CT genotypes in the chronic hepatitis C patients and healthy individuals were as follows: 10.8% vs. 11.3%, 38.7% vs. 46.2% and 50.3% vs. 42.5%. Also, the frequencies of rs8099917 TT, GG and GT genotypes in the chronic hepatitis C patients was 61.9%, 6.1% and 32% and in controls was 47.5%, 11.2% and 41.3%. The differences in the distribution of rs12979860 genotypes and alleles between HCV genotype 1 and HCV genotype 3a infected patients were statistically significant. CONCLUSION:The rs12979860 C allele is the favorable allele for the spontaneous clearance of HCV. It seems that the impact of IL-28B polymorphism on the spontaneous clearance of HCV genotype 3 is more prominent than HCV genotype 1, which results in the observation of higher rs12979860 C allele frequency in chronic hepatitis C patients with HCV genotype 3 than HCV genotype 1.
Project description: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.
Project description:BACKGROUND:Hepatitis C is a global health problem and represents a major cause of liver disease and socioeconomic burden. Effective antiviral therapy may prevent these complications, but the current treatment for patients with chronic hepatitis C virus (HCV) infection does not produce sustained virologic response. Therefore, identification of the determinants of response to treatment is a high priority. A number of host and viral factors have been associated with treatment outcomes. OBJECTIVES:To assess the associations of single nucleotide polymorphisms (SNP) of the IL28B and sustained virologic response (SVR) of patients with chronic hepatitis C to PEG-interferon/ribavirin therapy. MATERIALS AND METHODS:We searched PubMed, Medline and Cochrane Library, and found 7 eligible papers involved in this study. Then we performed a meta-analysis comparing the SVR rate at SNP of the IL28B in individuals with PEG-interferon/ribavirin therapy. Meanwhile, the SVR rate between different races and HCV genotypes was studied. RESULTS:The sustained virologic response rate was higher in patients with the rs12979860 CC and rs8099917 TT alleles in the IL28B SNP, comparing with the rs12979860 CT, or TT and rs8099917 TG or GG. Furthermore, a higher SVR was observed in the Caucasians than in Afro-Americans (OR = 3.85, 95% CI: 3.06-4.83); the percentage of rs12979860 TT genotype was lower in Caucasians (OR = 0.25, 95% CI: 0.20-0.31) and the percentage of rs12979860 CC genotype was higher in Caucasians than that of Afro-Americans (OR = 3.45, 95% CI = 2.68-4.44). Between different HCV genotypes, the SVR was much lower in those with HCV genotype 1 than those with genotype 2/3 (OR = 0.16, 95% CI: 0.11-0.24). CONCLUSIONS:IL28B is significantly associated with response to PEG-interferon/ribavirin therapy of patients with chronic HCV infection. Both the rs12979860 and rs8099917 alleles could be used as independent predictors of the treatment response. The rs12979860 allele in particular, is more important from our study. The polymorphism even explains part the difference in response rate between different ethnic groups and HCV genotypes.