Service d'Hépatologie, Hôpital Beaujon, Assistance Publique-Hôpitaux de Paris, Clichy, France.
Am J Pathol. 2011 Jun;178(6):2708-15. doi: 10.1016/j.ajpath.2011.02.021.
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.
自噬是一种受调控的过程,可参与清除细胞内微生物和抗原呈递。一些体外研究表明丙型肝炎病毒感染的肝细胞中自噬反应发生改变。本研究旨在评估慢性丙型肝炎(CHC)患者肝脏的自噬过程。纳入了 56 例 CHC 患者和 47 例对照患者(8 例为非酒精性脂肪性肝炎或酒精性肝病,18 例为慢性乙型肝炎病毒感染,21 例组织学检查无或轻度肝异常)。通过电子显微镜和微管相关蛋白轻链 3 免疫印迹评估自噬。使用轻链 3 免疫印迹,CHC 患者的自噬小体(轻链 3-II)形式明显高于对照组(P < 0.05)。使用定量电子显微镜分析,CHC 患者肝细胞中观察到的自噬小体中位数是对照组的六倍(P < 0.001)。相比之下,CHC 患者和对照组之间具有电子致密内容的成熟溶酶体数量没有差异,这表明自噬体与溶酶体之间融合缺乏。基因型和病毒载量均不影响自噬水平。总之,CHC 患者肝细胞中的自噬发生改变,可能是由于自噬过程的最后一步受阻。