Changes in autophagic response in patients with chronic hepatitis C virus infection

Am J Pathol. 2011 Jun;178(6):2708-15. doi: 10.1016/j.ajpath.2011.02.021.

Abstract

Autophagy is a regulated process that can be involved in the elimination of intracellular microorganisms and in antigen presentation. Some in vitro studies have shown an altered autophagic response in hepatitis C virus infected hepatocytes. The present study aimed at evaluating the autophagic process in the liver of chronic hepatitis C (CHC) patients. Fifty-six CHC patients and 47 control patients (8 with nonalcoholic steatohepatitis or alcoholic liver disease, 18 with chronic heptatitis B virus infection, and 21 with no or mild liver abnormalities at histological examination) were included. Autophagy was assessed by means of electron microscopy and microtubule-associated protein light chain 3 immunoblotting. Using light chain 3 immunoblotting, the form present on autophagic vesicle (light chain 3-II) was significantly higher in CHC patients than in controls (P < 0.05). Using quantitative electron microscopy analysis, the median number of autophagic vesicles observed in hepatocytes from CHC patients was sixfold higher than in overall controls (P < 0.001). In contrast, there was no difference between CHC patients and controls in the number of mature lysosomes with electron-dense contents arguing in favor of a lack of fusion between autophagosome and lysosome. Neither genotype nor viral load influenced the autophagy level. In conclusion, autophagy is altered in hepatocytes from CHC patients, likely due to a blockade of the last step of the autophagic process.

Publication types

  • Research Support, Non-U.S. Gov't

MeSH terms

  • Adult
  • Aged
  • Autophagy*
  • Case-Control Studies
  • Female
  • Hepacivirus / genetics
  • Hepacivirus / physiology*
  • Hepatitis C, Chronic / pathology*
  • Hepatitis C, Chronic / virology*
  • Hepatocytes / pathology
  • Hepatocytes / ultrastructure
  • Humans
  • Immunoblotting
  • Liver / metabolism
  • Liver / pathology
  • Liver / virology
  • Lysosomal Membrane Proteins / metabolism
  • Lysosomal-Associated Membrane Protein 2
  • Male
  • Microtubule-Associated Proteins / metabolism
  • Middle Aged
  • Viral Load
  • Young Adult

Substances

  • LAMP2 protein, human
  • Lysosomal-Associated Membrane Protein 2
  • Lysosomal Membrane Proteins
  • MAP1LC3A protein, human
  • Microtubule-Associated Proteins