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

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.