Project description:Background and aimsHepatitis G virus/GB virus-C (HGV/GBV-C) is a newly identified member of the Flaviviridae family. Its clinical significance in chronic hepatitis C infection remains controversial. There is a geographical difference in the distribution of GBV-C in the world. The frequency of GBV-C infection among hepatitis C virus (HCV) infected patients varies. The aim of the current study was to determine the prevalence and genotypes of GBV-C among Iranian patients infected with chronic HCV.MethodsInfection with GBV-C was surveyed in 71 chronic confirmed hepatitis C infected patients. These samples were collected at the Digestive Disease Research Center (DDRC) of Shariati Hospital, Tehran, Iran from January to October 2007. The 5'-UTR region of GBV-C RNA was detected using a novel in-house touchdown nested reverse transcription polymerase chain reaction (RT-PCR), the products were sequenced and the results were aligned and phylogenically analyzed.ResultsOf the 71 HCV-infected patients, 31 (43.6%) were found positive for GBV-C RNA. Sequencing and phylogenic analysis showed that the samples were Genotype 2 of GBV-C.ConclusionsIt seems that there is a high rate of GBV-C infection among Iranian patients infected with chronic HCV. In comparison with the six reference genotypes, it was observed that all the samples were categorized in Genotype 2 of GBV-C, prevalent in North America, Africa and in European countries.
Project description:BackgroundIL28B single nucleotide polymorphisms (SNPs) play important roles in the management of hepatitis C virus (HCV) infections and are strongly associated with spontaneous and treatment-induced HCV clearance.ObjectivesIn the present study, the association between IL28B variants and the progression of HCV infection in Egyptian patients infected with type 4a virus will be examined.Patients and methodsFrequencies of the protective genotype C/C of SNP, rs12979860 were determined in healthy subjects, spontaneous resolvers, and chronic HCV type 4 patients with low F scores and in patients with end stage liver disease (ESLD). This study included a total of 404 subjects. Patients infected with HCV type 4a (n = 304) were divided into; chronic hepatitis C (CHC) with low F scores (CHC, n = 110), end stage liver disease (n = 110), liver cirrhosis (LC) (n = 35) and hepatocellular carcinoma (HCC) patients (n = 75), spontaneous resolvers of HCV infection (n = 84) were also included. A healthy group representing the Egyptian population (n = 100) was also included in the genotyping of IL28B. The later was typed via a polymerase chain reaction based restriction fragment length polymorphism (PCR-RFLP) assay analysis on purified genomic DNA extracted from all individuals.ResultsA significant increase (P < 0.0005) was observed in frequencies of IL-28B rs12979860 C/C genotypes in the healthy population, than in the CHC, LC and HCC groups (C/C = 48%, 13%, 0%.and 0% respectively). On the other hand the C/C genotype was significantly higher (P < 0.0005) in spontaneous resolvers than in healthy subjects. A comparable significant increase in the frequency of C/T allele accompanied by mild elevation of T/T allele frequency, were detected along the progression towards ESLD.ConclusionsGenotype C/C is associated with viral clearance during acute infection. The sharp decline in the C/C genotype from healthy to CHC subjects and the total absence of the C/C genotype in ESLD suggests a central role of this genotype against HCV disease progression.
Project description:Recent studies have demonstrated that IL28B polymorphisms predict therapeutic responses in chronic hepatitis C virus (HCV)-treated patients; however, the effect on HCV viral diversity, particularly on the HCV protease gene, is not clear. This study sought to evaluate the effect of IL28B polymorphisms on HCV diversity at NS3/4 protease region, which may influence therapeutic response to an HCV protease inhibitor based regimen. Twenty-two patients co-infected with HIV and HCV genotype 1, treatment-naïve on stable HIV antiretroviral therapy initiating interferon-based treatment were evaluated. Plasma HCV NS3 gene diversity was analyzed by clonal analysis at baseline and end of treatment. IL28B (rs12979860) genotypes were tested for associations with virologic outcomes and diversity parameters. There was similar baseline NS3 diversity in patients with CC (favorable) genotype compared to those with CT/TT (unfavorable) genotypes. There was no significant association between IL28B genotype and baseline NS3 nucleotide p-distance, dS-dN, amino acid p-distance, or nucleotide changes. Among patients without a sustained virologic response, between baseline and follow-up there was a significant trend towards decreased diversity after treatment among patients with favorable genotype, which was not observed in unfavorable genotypes. In patients treated with peginterferon/ribavirin therapy, IL28B polymorphism was not associated with enhanced NS3 diversity at baseline. Among non-SVR patients with the less favorable genotype, there was no change in diversity after treatment. This suggests that IL28B genotype is unlikely to have a negative impact on subsequent HCV PI efficacy in patients co-infected with HIV and HCV patients who have previously failed HCV therapy.
Project description:Recent genome-wide association studies report that the SNP rs8099917, located 8.9 kb upstream of the start codon of IL28B, is associated with both disease chronicity and therapeutic response to pegIFN-? and RBV in patients infected with genotype 1 HCV. To determine the effect of rs8099917 variation on the response of HCV to therapy, we genotyped this variant in a cohort of 160 HCV/HIV-1 coinfected patients in our clinic unit who received combined peg-IFN-?/RBV therapy. The rs8099917 T/G or G/G genotypes were observed in 56 patients (35%). Treatment failure occurred in 80% of G-allele carriers versus 48% of non-carriers (P<0.0001). This result reveals that the G allele was strongly associated with treatment failure in this patient cohort. Importantly, a highly significant association was found between the G-allele and response to therapy in HCV genotype 1-infected patients (P<0.0001) but not in HCV genotype 3-infected patients. Multivariate analysis (odds ratio; 95% confidence interval; P value) indicated that the rs8099917 TT genotype was a strong predictor of treatment success (5.83; 1.26-26.92; P = 0.021), independent of baseline plasma HCV-RNA load less than 500 000 IU/ml (4.85; 1.18-19.95; P = 0.025) and absence of advanced liver fibrosis (5.24; 1.20-22.91; P = 0.025). These results reveal the high prevalence of the rs8099917 G allele in HCV/HIV-1 coinfected patients as well as its strong association with treatment failure in HCV genotype 1-infected patients. rs8099917 SNP genotyping may be a valid pre-treatment predictor of which patients are likely to respond to treatment in this group of difficult-to-treat HCV/HIV-infected patients.
Project description:The IL28B gene is associated with spontaneous or treatment-induced HCV viral clearance. However, the mechanism by which the IL28B single nucleotide polymorphism (SNP) affects the extra-hepatic HCV immune responses and its relationship to HCV pathogenesis have not been thoroughly investigated. To examine the mechanism by which IL28B affects HCV clearance. Forty Egyptian patients with chronic HCV infection receiving an Interferon/ribavirin treatment regimen were enrolled into this study. There were two groups: non-responders (NR; n = 20) and sustained virologic responders (SVR; n = 20). The initial plasma HCV viral loads prior to treatment and IL28B genotypes were determined by quantitative RT-PCR and sequencing, respectively. Liver biopsies were examined to determine the inflammatory score and the stage of fibrosis. Colonic regulatory T cell (Treg) frequency was estimated by immunohistochemistry. No significant association between IL28B genotypes and response to therapy was identified, despite an odds ratio of 3.4 to have the TT genotype in NR compared to SVR (95 % confidence interval 0.3-35.3, p = 0.3). Patients with the TT-IL28Brs12979860 genotype (unfavorable genotype) have significantly higher frequencies of colonic Treg compared to the CT (p = 0.04) and CC (p = 0.03) genotypes. The frequency of colonic Treg cells in HCV-infected patients had a strong association with the IL-28B genotype and may have a significant impact on HCV clearance.
Project description:Until recently, the standard treatment of chronic hepatitis C virus (HCV) infection was a combination therapy with PEG-IFN-? plus ribavirin. Previous studies have proven that several markers predict the outcome of such therapy, e.g., pretreatment plasma levels of interferon inducible protein IP-10, HCV RNA and IL28B-related single nucleotide polymorphisms (SNP). Altered activity of tryptophan metabolizing enzyme indoleamine 2,3-dioxygenase (IDO) has been also shown in patients suffering from HCV infection. In this study, we investigated whether IL28B SNP in patients infected with HCV is related to the tryptophan breakdown rate. Before therapy, serum tryptophan and kynurenine concentrations were determined in 25 patients with established HCV infection and the kynurenine to tryptophan ratio (KYN/TRP) was calculated as an estimate of the tryptophan breakdown rate. In parallel, neopterin and nitrite concentrations were determined. A significant difference of serum KYN/TRP existed between the three IL28B polymorphism groups: C/C genotype had the highest and T/T genotype had the lowest KYN/TRP (p < 0.05). Likewise, C/C genotype was associated with higher KYN/TRP than non-C/C genotype (p = 0.01). There was a smaller difference between the three groups regarding the absolute kynurenine concentrations, the C/C genotype being associated with higher kynurenine concentrations. None of the other comparisons revealed any statistical significance. In conclusion, patients with C/C genotype presented with the highest tryptophan breakdown rate already before antiretroviral therapy with IFN-?/ribavirin. The differences in tryptophan metabolism might relate to HCV clearance and also to side effects of IFN-? therapy.
Project description:Recent genome-wide association studies have identified two host single-nucleotide polymorphisms (SNPs) near the IL28B gene (rs12979860 C/T and rs8099917 T/G) that are associated with sustained virological response in patients infected with the hepatitis C virus. Herein, we describe a rapid multiplexed dual-color fluorescence resonance energy transfer (FRET) probe assay that accurately genotypes for both SNPs simultaneously. A single-nucleotide extension assay was also developed for verification of genotypes. Agreement (100%) was observed in genotype calls between the FRET and single-nucleotide extension methods for both SNPs, yielding 100% analytical sensitivity and specificity. By using the FRET assay, 443 samples of varying ethnic backgrounds were genotyped and six different compound genotypes (rs12979860/rs8099917) were detected in whites, Asians, Middle Easterners, Hispanics, and African Americans, at the following frequencies: CC/TT (39.2%, 78.9%, 40.0%, 33.9%, and 16.8%), CT/TT (20.8%, 0%, 40%, 9.3%, and 37.0%), TT/TT (2.4%, 0%, 0%, 3.4%, and 35.3%), CT/TG (24.0%, 19.7%, 20%, 39.8%, and 3.4%), TT/TG (8.0%, 1.4%, 0%, 3.4%, and 5.9%), and TT/GG (5.6%, 0%, 0%, 10.2%, and 1.7%), respectively. The multiplexed FRET assay can be used to effectively genotype for both SNPs in a single tube, with high analytical sensitivity and specificity.
Project description:Genotyping of hepatitis C virus (HCV) plays an important role in the treatment of HCV. As new genotype-specific treatment options become available, it has become increasingly important to have accurate HCV genotype and subtype information to ensure that the most appropriate treatment regimen is selected. Most current genotyping methods are unable to detect mixed genotypes from two or more HCV infections. Next generation sequencing (NGS) allows for rapid and low cost mass sequencing of viral genomes and provides an opportunity to probe the viral population from a single host. In this paper, the possibility of using short NGS reads for direct HCV genotyping without genome assembly was evaluated. We surveyed the publicly-available genetic content of three HCV drug target regions (NS3, NS5A, NS5B) in terms of whether these genes contained genotype-specific regions that could predict genotype. Six genotypes and 38 subtypes were included in this study. An automated phylogenetic analysis based HCV genotyping method was implemented and used to assess different HCV target gene regions. Candidate regions of 250-bp each were found for all three genes that have enough genetic information to predict HCV genotypes/subtypes. Validation using public datasets shows 100% genotyping accuracy. To test whether these 250-bp regions were sufficient to identify mixed genotypes, we developed a random primer-based method to sequence HCV plasma samples containing mixtures of two HCV genotypes in different ratios. We were able to determine the genotypes without ambiguity and to quantify the ratio of the abundances of the mixed genotypes in the samples. These data provide a proof-of-concept that this random primed, NGS-based short-read genotyping approach does not need prior information about the viral population and is capable of detecting mixed viral infection.
Project description:Background & aimsA 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.Method197 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.ResultsThe 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.ConclusionsThe genetic polymorphisms of IL28B had no impact on treatment responses in GT2 patients.
Project description:BackgroundThree single nucleotide polymorphisms (SNPs) near interleukin-28B (IL-28B) gene were shown to be highly associated with treatment response (SVR) in patients with chronic hepatitis C virus (HCV) infection. There is limited data about the role of single and combined IL-28B polymorphisms in HCV-infected Polish population.ObjectivesThis study's aim was to determine predictability of three IL-28B gene polymorphisms and other known prognostic factors on the treatment response in HCV genotype 1 and 4 infected Polish patients. The effect of IL-28B polymorphisms on therapy was also compared with other known prognostic factors.Patients and methodsWe genotyped IL-28B polymorphisms (rs12979860, rs12980275 and rs8099917) by polymerase chain reaction-based restriction fragment length polymorphism assay in a group of 293 patients from which a selected cohort of 174 treatment-naiev patients underwent treatment.ResultsWe showed that rs12979860 CC [odds ratio (OR) = 4.6, P < 0.001], rs12980275 AA (OR = 2.9, P = 0.002) and rs8099917 TT (OR = 2.2, P = 0.016) genotypes were associated with successful treatment compared to the rs12979860 CT-TT, rs12980275 AG-GG and rs8099917 TG-GG, respectively. Patients bearing of IL-28B profile including the three favourable genotypes do not have much chance of a recovery (OR = 3.4, P = 0.002). Except for IL-28B polymorphisms, there was no association of SVR with any other pretreatment clinical data in analyzed group. The correlation of SNPs with other host and viral factors revealed association of favorable genotypes of IL-28B markers with high levels of alanine aminotransferase and baseline HCV viral load.ConclusionsIL-28B polymorphisms were the strongest pretreatment predictors of response to pegylated interferon and ribavirin in Polish patients chronically infected with HCV genotype 1 and 4. This study confirm the strongest impact of IL-28B rs12979860 on SVR, nevertheless rs12980275 AA seems to be more important than rs8099917 TT in predicting positive treatment response.