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Background: Interferon is well thought-out as the key defence against all infections including HCV. The only treatment for HCV infection is pegylated interferon alpha (IFN-α) but unluckily more than half of the infected individuals do not act in response to the cure and become chronic HCV carriers. The mechanism how HCV induce interferon resistance is still elusive. It is recently reported that HCV envelope protein 2 interacts with PKR which is the interferon-inducible protein kinase and which in turn blocks the activity of its target molecule called eukaryotic initiation factor elF2. Sequence analysis of Envelope protein reveals it contains a domain homologous to phosphorylation sites of PKR andthe translation initiation factor eIF2alpha. Envelope protein competes for phosphorylation with PKR. Inhibition of kinase activity of PKR is postulated as a mechanism of to interferon (IFN) resistance., Results: Present study involves the insilico investigation of possible role of potential phosphorylation in envelope 2 protein of 3a genotype in interferon resistance. Envelope protein coding genes were isolated from local HCV isolates, cloned and sequenced. Phylogenetic analysis was done and tertiary structure of envelope gene was predicted. Visualization of phosphorylation in tertiary structure reveals that residue 266 and 267 of envelope gene 2 are surface exposed and their phosphorylation may compete with the phosphorylation of PKR protein and possibly involved in mediating Interferon Resistance., Conclusion: A hybrid in-silico and wet laboratory approach of motif prediction, evolutionary and structural analysis has pointed out serine 266 and 267 of the HCV E2 gene as a hopeful claimant for the serine phosphorylation. Recognition of these nucleotide variations may assist to propose genotype precise therapy to avoid and resolve HCV infections.

Objective To evaluate the association of genetic variation in interleukin 28 B ( IL-28B) gene and viral factors with treatment outcome in chronic hepatitis C virus (HCV)-infected patients in Pakistan. Methods Patients with chronic HCV infection who received interferon plus ribavirin combination therapy were enrolled in the study. The viral loads were checked at the third and sixth month of treatment and 6 months after the completion of the treatment. Genotyping of single-nucleotide polymorphism ( SNP) rs12979860 of IL-28B gene was performed by the restriction fragment length polymorphism method and direct sequence analysis. Results A total of 111 patients successfully completed antiviral therapy and the follow-up period. Early virological response ( EVR) and a sustained virological response ( SVR) were achieved in 92 and 91 patients, respectively. Patients infected with HCV genotype 3a had a higher SVR rate compared with other HCV genotypes. A higher C allele frequency (81.9%) was observed in patients with SVR than those with non- SVR ( P = 0.00001). The odds ratio of achieving SVR was more than 10-fold greater for the CC genotype than the CT/ TT genotypes of SNP rs12979860 ( OR 10.351, 95% CI 1.925-55.653, P = 0.006). Other positive predictors observed for SVR were female gender and EVR. Conclusion The CC genotype of IL-28B SNP rs12979860 is an independent predictive factor for SVR in chronic HCV-infected patients in Pakistan. [ABSTRACT FROM AUTHOR]

Background: Current standard therapy commonly followed for chronic Hepatitis C Virus (HCV) in Pakistan is interferon alpha plus ribavirin combination therapy (IFN α/ribavirin) and pegylated interferon plus ribavirin (PegIFN/ribavirin). PegIFN/ribavirin has increased rate of sustained virological response than standard IFN α/ribavirin therapy. Objective of current study was to analyze rate of early and delayed response to antiviral treatment as well as rate of relapse response in patients following standard treatment IFN α/ribavirin and in patients following pegylated interferon treatment. Methods: Baseline serum samples of 153 patients enrolled for IFN α/ribavirin and 50 patients for PegIFN/ribavirin were collected. After total RNA extraction, genotyping was and HCV RNA viral load was done. Subsequently HCV RNA viral load was estimated at 4 weeks of treatment, at 12 weeks, at 24 or 48 weeks and finally after 6 months follow up period. All the data was statistically analyzed using fisher's exact test. Results: Total 86 patients out of 153 patients following conventional IFN α/ribavirin therapy completed treatment and 69% of them showed Rapid Virological Response (RVR). Whereas 50 patients following PegIFN/ribavirin treatment completed treatment and 80% of them achieved RVR. Total 64 out of 86 patients following IFN α/ribavirin therapy completed follow up period and 53.5% of them achieved Sustainded Virologcal Response (SVR). Forty-five out of total 50 patients who received PegIFN/ribavirin treatment completed 6 months follow up period and among these 70% achieved SVR. SVR rates were significantly associated with RVR (p < 0.001), age (p < 0.001) and gender (p < 0.01) Conclusions: Rate of sustained virological response can be determined by factors like rapid virological response and age since they share significant association with one another. More over rate of SVR was more prominent in males than in females. [ABSTRACT FROM AUTHOR]

Background: Hepatitis C is a major health problem affecting more than 200 million individuals in world including Pakistan. Current treatment regimen consisting of interferon alpha and ribavirin does not always succeed to eliminate virus completely from the patient's body. Results: Interferon induced antiviral protein kinase R (PKR) has a role in the hepatitis C virus (HCV) treatment as dsRNA activated PKR has the capacity to phosphorylate the serine and threonine of E2 protein and dimerization viral RNA. E2 gene of hepatitis C virus (HCV) genotype 1 has an active role in IFN resistance. E2 protein inhibits and terminates the kinase activity of PKR by blocking it in protein synthesis and cell growth. This brings forward a possible relation of E2 and PKR through a mechanism via which HCV evades the antiviral effect of IFN. Conclusion: A hybrid in-silico and wet laboratory approach of motif prediction, evolutionary and structural anlysis has pointed out serine 75 and 277 of the HCV E2 gene as a promising candidate for the serine phosphorylation. It is proposed that serine phosphorylation of HCV E2 gene has a significant role in interferon resistance. [ABSTRACT FROM AUTHOR]

Hepatitis B virus (HBV) is one of the leading health problem with up to 350 million affected people worldwide including 4.5 million only in Pakistan. It has mortality rate of 0.5 to 1.2 million per year worldwide. Pakistan lies in the endemic region with 3-5% HBV carrier rate in the country. The present article reviews the literature on the treatment response of HBV prevalent in Pakistani population. The average treatment response of Lamivudine and interferon-a is 25.81% and 47.95%, respectively. Peg-Interferon was shown to be not effective against the HBV/HCV (hepatitis C virus)/HDV (hepatitis Delta virus) co-infection. The present study reveals that interferon-a is the most effective therapy available for HBV infection prevalent in Pakistani population. Genotype C & D are the most common HBV genotypes in Pakistan and are associated with increased severity and less response to interferon therapy. This poses a great challenge for physicians and researchers and further studies are needed to describe the outcome of the current therapies recommended against HBV infection in Pakistani population. [ABSTRACT FROM AUTHOR]

Hepatitis C virus (HCV) is a member of Flaviviridae family and one of the major causes of liver disease. There are about 175 million HCV infected patients worldwide that constitute 3% of world's population. The main route of HCV transmission is parental however 90% intravenous drug users are at highest risk. Standard interferon and ribavirin remained a gold standard of chronic HCV treatment having 38-43% sustained virological response rates. Currently the standard therapy for HCV is pegylated interferon (PEG-INF) with ribavirin. This therapy achieves 50% sustained virological response (SVR) for genotype 1 and 80% for genotype 2 & 3. As pegylated interferon is expensive, standard interferon is still the main therapy for HCV treatment in under developed countries. On the other hand, studies showed that pegylated IFN and RBV therapy has severe side effects like hematological complications. Herbal medicines (laccase, proanthocyandin, Rhodiola kirilowii) are also being in use as a natural and alternative way for treatment of HCV but there is not a single significant report documented yet. Best SVR indicators are genotype 3 and 2, < 0.2 million IU/mL pretreatment viral load, rapid virological response (RVR) rate and age <40 years. New therapeutic approaches are under study like interferon related systems, modified forms of ribavirin, internal ribosome entry site (HCV IRES) inhibitors, NS3 and NS5a inhibitors, novel immunomodulators and specifically targeted anti-viral therapy for hepatitis C compounds. More remedial therapies include caspase inhibitors, anti-fibrotic agents, antibody treatment and vaccines. [ABSTRACT FROM AUTHOR]

Abstract: Hepatitis C virus (HCV), a major cause of liver disease throughout the world, is difficult to treat with interferon (IFN) (and various formulations and combinations thereof) being the only approved molecule available. It has been investigated recently that proinflammatory chemokine interleukin-8 (IL-8) induced by HCV partially inhibits the antiviral IFN-α therapy. Therefore, the current study was aimed to prospectively utilize the baseline IL-8 levels in the HCV infected serum and predicts its role in sustained virological response (SVR) to IFN-α+ribavirin therapy, in chronic HCV patients in Pakistan. One hundred and ten hepatitis C patients without any other infections underwent IFN-α+ribavirin combination treatment. Baseline IL-8 levels were determined before starting of the therapy for all these patients. Fifteen normal volunteers negative for HCV were kept as control. The baseline IL-8 levels were found significantly higher in all HCV positive patients as compared to normal healthy volunteers (1083.54±85.72pg/ml versus 6.99±1.05pg/ml [mean±SEM], p <0.01) and were also significantly higher in non-responders than responders (p <0.05). Comparatively higher mean baseline IL-8 levels were observed in non-responders (2442.02±159.92pg/ml), than late (1009.31±45.31) and rapid (540.91±27.06pg/ml) responders. Significant relation was observed between baseline IL-8 level and response to IFN therapy (p <0.01). Results of this study suggest that increased levels of IL-8 in HCV infection might be involved in pathogenesis, persistence and resistance to IFN-α+ribavirin combination therapy. [Copyright &y& Elsevier]