NS3 Variability in Hepatitis C Virus Genotype 1A Isolates from Liver Tissue and Serum Samples of Treatment-Naïve Patients with Chronic Hepatitis C

Intervirology. 2018;61(1):1-8. doi: 10.1159/000489307. Epub 2018 Jul 18.

Abstract

Background: Hepatitis C virus (HCV) NS3 resistance-associated substitutions (RASs) reduce HCV susceptibility to protease inhibitors. Little is known about NS3 RASs in viral isolates from the liver of chronic hepatitis C (CHC) patients infected with HCV genotype-1a (G1a).

Aim: The objective of this work was to study NS3 variability in isolates from the serum and liver of HCV-G1a-infected patients naïve to direct-acting antivirals (DAAs).

Methods: NS3 variability of HCV-G1a isolates from the serum and liver of 11 naïve CHC patients, and from sera of an additional 20 naïve CHC patients, was investigated by next-generation sequencing.

Results: At a cutoff of 1%, NS3 RASs were detected in all the samples examined. At a cutoff of 15%, they were found in 54.5% (6/11) and 27.3% (3/11) of the paired liver and serum samples, respectively, and in 22.5% (7/31) of the overall serum samples examined. Twenty-six out of thirty-one (84%) patients showed NS3 variants with multiple RASs. Phylogenetic analysis showed that NS3 sequences clustered within 2 clades, with 10/31 (32.2%) patients infected by clade I, 15/31 (48.8%) by clade II, and 6/31 (19.3%) by both clades.

Conclusions: Though the number of patients examined was limited, NS3 variants with RASs appear to be major components of both intrahepatic and circulating viral quasispecies populations in DAA-naïve patients.

Keywords: Chronic hepatitis C; Genotype-1a; Hepatitis C virus.

MeSH terms

  • Adult
  • Amino Acid Substitution
  • Antiviral Agents / pharmacology
  • Drug Resistance, Viral
  • Female
  • Genetic Variation*
  • Genotype
  • Hepacivirus / enzymology*
  • Hepacivirus / genetics
  • Hepatitis C, Chronic / epidemiology
  • Hepatitis C, Chronic / virology*
  • High-Throughput Nucleotide Sequencing
  • Humans
  • Italy / epidemiology
  • Liver / virology
  • Male
  • Middle Aged
  • Phylogeny
  • Protease Inhibitors / pharmacology
  • Serum / virology
  • Viral Nonstructural Proteins / genetics*

Substances

  • Antiviral Agents
  • NS3 protein, hepatitis C virus
  • Protease Inhibitors
  • Viral Nonstructural Proteins