Maria Lorena Abate

IL28B is associated with response to chronic hepatitis C interferon-alpha and ribavirin therapy

Hepatitis C virus (HCV) infects 3% of the worlds population. Treatment of chronic HCV consists of a combination of PEGylated interferon-α (PEG-IFN-α) and ribavirin (RBV). To identify genetic variants associated with HCV treatment response, we conducted a genome-wide association study of sustained virological response (SVR) to PEG-IFN-α/RBV combination therapy in 293 Australian individuals with genotype 1 chronic hepatitis C, with validation in an independent replication cohort consisting of 555 individuals. We report an association to SVR within the gene region encoding interleukin 28B (IL28B, also called IFNλ3; rs8099917 combined P = 9.25 × 10−9, OR = 1.98, 95% CI = 1.57–2.52). IL28B contributes to viral resistance and is known to be upregulated by interferons and by RNA virus infection. These data suggest that host genetics may be useful for the prediction of drug response, and they also support the investigation of the role of IL28B in the treatment of HCV and in other diseases treated with IFN-α.

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.

Vijayaprakash Suppiah and colleagues show that genotyping hepatitis C patients for the IL28B, HLA-C, and KIR genes improves the ability to predict whether or not patients will respond to antiviral treatment.

Hepatitis B virus unable to secrete e antigen and response to interferon in chronic hepatitis B

BACKGROUND Anti-hepatitis e antigen-positive chronic hepatitis B is a progressive liver disease associated with precore mutant hepatitis B virus (HBV) and poor response to interferon. Therefore, precore mutant HBV may behave as an interferon-resistant virus. The relations between the prevalences of wild-type and precore mutant HBVs in baseline viremias and response to interferon were analyzed. METHODS Sera from 115 patients (59 treated and 56 untreated, followed up for 30 months) were tested using a quantitative oligonucleotide hybridization assay. RESULTS Spontaneous or interferon-induced recoveries were observed in 28.5% (6 of 21) and 47.3% (18 of 38) or in 0% (0 of 35) and 19% (4 of 21) of the patients with wild-type prevalent or mutant prevalent HBVs, respectively. Relapses occurred in 85.7% (12 of 14) and 19.4% (4 of 21) of treated patients with prevalent precore mutant and prevalent wild-type HBV, respectively (P = 0.0001). High precore mutant HBV levels (> 20% of total viremia) were associated with the lack of permanent response to interferon (P = 0.01). CONCLUSIONS Precore mutant HBV can influence the response to interferon when it reaches significant serum levels (> 20% of total viremia). Therefore, chronic hepatitis B should be treated as early as possible in its natural history before precore mutant HBV is selected as a prevalent virus.

Sites and mechanisms of insulin resistance in nonobese, nondiabetic patients with chronic hepatitis C

Chronic hepatitis C (CHC) has been associated with type 2 diabetes and insulin resistance, but the extent of impairment in insulin action, the target pathways involved, and the role of the virus per se have not been defined. In this study, we performed a euglycemic hyperinsulinemic clamp (1 mU · minute−1 · kg−1) coupled with infusion of tracers ([6,6‐2H2]glucose, [2H5]glycerol) and indirect calorimetry in 14 patients with biopsy‐proven CHC, who were selected not to have any features of the metabolic syndrome, and in seven healthy controls. We also measured liver expression of inflammatory cytokines/mediators and tested their association with the metabolic parameters. Compared to controls, in patients with CHC: (1) total glucose disposal (TGD) during the clamp was 25% lower (P = 0.003) due to impaired glucose oxidation (P = 0.0002), (2) basal endogenous glucose production (EGP) was 20% higher (P = 0.011) and its suppression during the clamp was markedly reduced (P = 0.007), and (3) glycerol appearance was not different in the basal state or during the clamp, but lipid oxidation was less suppressed by insulin (P = 0.004). Lipid oxidation was higher in patients with CHC who had more steatosis and was directly related to EGP, TGD, and glucose oxidation. The decreased insulin‐stimulated suppression of EGP was associated with increased hepatic suppressor of cytokine signaling 3 (SOCS3; P < 0.05) and interleukin‐18 (P < 0.05) expression. Conclusion: Hepatitis C infection per se is associated with peripheral and hepatic insulin resistance. Substrate competition by increased lipid oxidation and possibly enhanced hepatic expression of inflammatory cytokines/mediators could be involved in the defective glucose regulation. (HEPATOLOGY 2009.)

Italian blood donors with anti-HBc and occult hepatitis B virus infection

Background and Objectives Occult hepatitis B virus (HBV) infection might allow the release of viremic units into the blood supply network if blood is tested only for hepatitis B surface antigen (HBsAg). The aim of our study was to evaluate the actual prevalence, viral load and genotype of occult HBV infections among first-time blood donors in north-western Italy and to suggest a way to minimize risks of transmission of this infection. Design and Methods We assayed 6313 consecutive blood donors for antibodies to HBV core antigen (anti-HBc) in addition to mandatory screening. HBsAg-negative/anti-HBc-positive donors were assayed for antibodies to HBsAg (anti-HBs) and for HBV-DNA using COBAS Ampliscreen HBV (RocheTM) on individual donations. All HBV-DNA-positive samples underwent confirmatory testing with additional polymerase chain reaction-based assays. Results The prevalence of anti-HBc positive subjects was 4.85%. Fourteen out of 288 blood donors (4.86%) were confirmed to have circulating HBV-DNA at a low level (range 8–108 IU/mL). All viremic donors were also anti-HBs-positive. Interpretation and Conclusions We estimate that in north-western Italy up to 2298 units per million donated units from first-time donors may contain HBV-DNA. The risk of an HBV-DNA positive unit from an occult carrier being released into the blood supply is more than 100 times higher than the estimated residual risk related to the window phase of HBV infection in our country. The potential infectivity of these units is debated, but their use cannot be considered safe at least in immunocompromised patients.

Incidence of Type 2 Diabetes Mellitus and Glucose Abnormalities in Patients With Chronic Hepatitis C Infection by Response to Treatment: Results of a Cohort Study

BACKGROUND:Patients with chronic hepatitis C are at risk of developing type 2 diabetes mellitus (DM) and impaired fasting glucose (IFG), and this risk may increase among hepatitis C virus (HCV) patients not responding to an antiviral therapy.AIM:To compare the incidence of glucose abnormalities (IFG or DM) after an antiviral therapy between HCV+ patients with a long-term virological response (LTR) and nonresponders (NR; persistently positive HCV-RNA).METHODS:All 202 HCV+ patients without the baseline glucose abnormalities enrolled by our center in investigational trials or routinely treated with interferon (IFN)/peginterferon (Peg-IFN) (+/– ribavirin) from 1988 to 2001, with the available baseline sera stored at −80°C, were considered. The baseline data included age, sex, body mass index (BMI), viral load, genotype, liver histologic staging and steatosis, glucose, and cholesterol. The homeostatic assessment of insulin resistance (HOMA-IR) was calculated in the baseline serum. The incidence of IFG or DM at the end of follow-up was compared between patients with LTR and NR.RESULTS:After a median follow-up of 8.0 yr (range 5–16), the cumulative risk of DM (N = 7) or IFG (N = 33) among the 202 HCV+ included patients was 16.9% (95% confidence interval [CI] 11.3–22.5). The 8-yr risk was not significantly lower between LTRs (14.5%) compared to NRs (18.8%) (hazard ratio [HR] 0.60, CI 0.30–1.20, P= 0.16). The HR adjusted for the baseline risk factors for DM and the predictors of a poor response (age, sex, HOMA-IR, BMI, family history of diabetes, HCV genotype 1, high viral load, cirrhosis, and steatosis) was 0.88 (CI 0.38–2.02, P= 0.76). Among other factors, those more associated to IFG-DM were an increasing age (P= 0.017), a higher BMI (P= 0.054), and a family history of DM (P= 0.065).CONCLUSIONS:After adjustment for several baseline risk factors, the incidence of glucose abnormalities was not significantly different between LTRs and NRs. Our data suggest that HCV clearance does not significantly reduce the risk of glucose intolerance.

Identification of improved IL28B SNPs and haplotypes for prediction of drug response in treatment of hepatitis C using massively parallel sequencing in a cross-sectional European cohort

BackgroundThe hepatitis C virus (HCV) infects nearly 3% of the Worlds population, causing severe liver disease in many. Standard of care therapy is currently pegylated interferon alpha and ribavirin (PegIFN/R), which is effective in less than half of those infected with the most common viral genotype. Two IL28B single nucleotide polymorphisms (SNPs), rs8099917 and rs12979860, predict response to (PegIFN/R) therapy in treatment of HCV infection. These SNPs were identified in genome wide analyses using Illumina genotyping chips. In people of European ancestry, there are 6 common (more than 1%) haplotypes for IL28B, one tagged by the rs8099917 minor allele, four tagged by rs12979860.MethodsWe used massively parallel sequencing of the IL28B and IL28A gene regions generated by polymerase chain reaction (PCR) from pooled DNA samples from 100 responders and 99 non-responders to therapy, to identify common variants. Variants that had high odds ratios and were validated were then genotyped in a cohort of 905 responders and non-responders. Their predictive power was assessed, alone and in combination with HLA-C.ResultsOnly SNPs in the IL28B linkage disequilibrium block predicted drug response. Eighteen SNPs were identified with evidence for association with drug response, and with a high degree of confidence in the sequence call. We found that two SNPs, rs4803221 (homozygote minor allele positive predictive value (PPV) of 77%) and rs7248668 (PPV 78%), predicted failure to respond better than the current best, rs8099917 (PPV 73%) and rs12979860 (PPV 68%) in this cross-sectional cohort. The best SNPs tagged a single common haplotype, haplotype 2. Genotypes predicted lack of response better than alleles. However, combination of IL28B haplotype 2 carrier status with the HLA-C C2C2 genotype, which has previously been reported to improve prediction in combination with IL28B, provides the highest PPV (80%). The haplotypes present alternative putative transcription factor binding and methylation sites.ConclusionsMassively parallel sequencing allowed identification and comparison of the best common SNPs for identifying treatment failure in therapy for HCV. SNPs tagging a single haplotype have the highest PPV, especially in combination with HLA-C. The functional basis for the association may be due to altered regulation of the gene. These approaches have utility in improving diagnostic testing and identifying causal haplotypes or SNPs.

Outcome of chronic delta hepatitis in Italy: a long-term cohort study.

BACKGROUND & AIMS To investigate the impact of HDV infection on morbidity and mortality of patients. PATIENTS AND METHODS This was a retrospective study on 188 patients that underwent a program of periodic surveillance until 2008. The demographic data, stage of liver disease, treatment efficacy, development of liver complications (ascites, oesophageal bleeding, encephalopathy), and survival were registered. A Cox regression analysis was carried out to determine the impact of viral and patient features on survival. RESULTS At baseline, 126 patients (67%) tested positive for serum IgM anti-HDV antibodies, 171 (91%) for anti-HBe, 175 (93%) for serum HDV-RNA, and 61 (33%) for serum HBV-DNA. Eighty-two patients (43%) had chronic hepatitis at histology; the remaining 106 individuals had a clinical/histological diagnosis of cirrhosis. Ninety-six patients received interferon (n = 90) or lamivudine (n = 6) therapy, and 27 of them (30%) attained a sustained response. During follow up, 21 patients with chronic hepatitis progressed to cirrhosis. Of the 127 cirrhotic patients, hepatic decompensation occurred in 42 patients (33%) and hepatocellular carcinoma in 17 (13%). The 5- and 10-year survival free of events were 96.8% and 81.9%, respectively, for patients with chronic hepatitis, and 83.9% and 59.4% for cirrhotics (p<0.01). At multivariate analysis, lack of antiviral therapy (p = 0.01), cirrhosis at presentation (p<0.01), and male sex (p = 0.03) independently predicted a worse outcome. CONCLUSION HDV liver disease lasts several decades. Half of all patients who develop cirrhosis later will advance to liver failure. At present, interferon therapy is recommended as soon as possible to slow or alter the natural course of liver disease.

Four years of treatment with lamivudine: clinical and virological evaluations in HBe antigen-negative chronic hepatitis B.

Aim : To evaluate the clinical and virological impact of the prolonged use of lamivudine in 94 patients with HBe antigen‐negative chronic hepatitis B.

‘e’ Antigen defective hepatitis B virus and course of chronic infection

We studied the relations between HBV heterogeneity and different phases of HBV infection and disease in 145 HBsAg-positive carriers followed-up for 28 months (range 24-60 months). Viraemia was characterized for the relative prevalence of wild-type and HBeAg minus HBVs after HBV-DNA amplification by PCR using an oligonucleotide hybridization assay. HBeAg minus HBV was detected in 27% of immunotolerant HBV carriers, in 67% of patients with chronic hepatitis B (immunoelimination phase) and in 17% of HBsAg carriers with latent infection. Serum HBV-DNA and IgM anti-HBc became undetectable and ALT levels normalized, either spontaneously or after interferon therapy in 12 (36.3%) of 33 patients with an exclusive wild-type viraemia, but only in two (5.7%) of 35 patients with homogeneous HBeAg minus HBV (p = 0.005). An HBeAg minus viraemia higher than 20% was associated, in both HBeAg- and anti-HBe-positive patients, with HBV-induced liver disease and an unfavourable outcome of hepatitis. These findings suggest that surgence of HBeAg defective HBV is a virus strategy to survive under peculiar conditions dictated by the interplay between HBV and the hosts immune system. The HBeAg/anti-HBe serological status is determined not only by the extent of virus replication and integration of HBV-DNA into cellular DNA but also by heterogeneity of HBV. The study of HBV heterogeneity in baseline sera of patients undergoing antiviral therapy appears to have a predictive value of the outcome of HBV infection in the single patient.