Evaluation of an automated, highly sensitive, real-time PCR-based assay (COBAS Ampliprep/COBAS TaqMan) for quantification of HCV RNA.

Background: Diagnosis of hepatitis C virus (HCV) infection and its therapy is based on qualitative and quantitative measurement of HCV RNA.

Objectives: A new assay that employs automated specimen extraction and real-time RT-PCR (COBAS Ampliprep/COBAS TaqMan, "CAP/CTM", Roche Diagnostics, Pleasanton, USA) was designed for linear quantification and highly sensitive detection of HCV RNA.

Study Design: The performance characteristics of CAP/CTM were compared to standard RT-PCR-based COBAS Amplicor Monitor 2.

The hepatitis C virus NS5A protein and response to interferon alpha: mutational analyses in patients with chronic HCV genotype 3a infection from India.

The hepatitis C virus (HCV) non-structural (NS)5A protein is linked to interferon alpha resistance in vitro and higher numbers of NS5A amino acid (aa) variations in HCV 1a/b isolates are associated with virologic response to interferon alpha-based therapy in vivo. Here, we aimed to study NS5A aa variations in Indian patients undergoing interferon alpha/ribavirin treatment infected with HCV 3a. The NS5A region [aa 2194-2401, comprising interferon sensitivity determining region, protein kinase resource (PKR) binding domain, V3 region] was sequenced from pre-treatment sera of 24 patients with HCV 3a infection.

Clinical significance of in vitro replication-enhancing mutations of the hepatitis C virus (HCV) replicon in patients with chronic HCV infection.

Background: Mutations in nonstructural (NS) hepatitis C virus (HCV) proteins enhance replication in HCV-1a/b replicons. The prevalence of such mutations and their clinical significance in vivo are unknown.

Methods: Parts of HCV NS3 and NS4B-NS5B genes that included 31 in vitro replication-enhancing sites were sequenced for 26 patients with chronic HCV genotype 1 infection.