title: Quantitation of covalently closed circular hepatitis B virus DNA in chronic hepatitis B patients.
abstract: This study examined a signal amplification assay, the Invader assay, for the quantitation of hepatitis B virus (HBV) covalently closed circular DNA (cccDNA) in liver biopsies and sera. DNA was extracted from liver biopsy and serum samples were collected from 16 hepatitis B e antigen (HBeAg)-positive and 36 antibody-to-HBeAg-positive (anti-HBe-positive) chronic hepatitis B patients. The amount of total HBV DNA and cccDNA was measured using the Invader assay. Anti-HBe-positive patients had lower median total intrahepatic HBV DNA (P < .001) and intrahepatic cccDNA levels (P = .001) than HBeAg-positive patients. Intrahepatic cccDNA correlated positively with the total intrahepatic HBV DNA (r = 0.950, P < .001). However, the proportion of intrahepatic HBV DNA in the form of cccDNA was inversely related to the amount of total intrahepatic HBV DNA (r = -0.822, P < .001). A small amount of cccDNA was detected in 39 of 52 (75%) serum samples. Anti-HBe-positive patients had lower median serum cccDNA levels than HBeAg-positive patients (P = .002). Serum HBV DNA correlated positively with intrahepatic total HBV DNA (r = 0.778, P < .001) and intrahepatic cccDNA (r = 0.481, P = .002). In conclusion, the Invader assay is a reliable assay for the quantitation of cccDNA. Serum and intrahepatic total HBV DNA and cccDNA levels become lower as the disease progresses from HBeAg-positive to anti-HBe-positive phase, with cccDNA becoming the predominant form of intrahepatic HBV DNA.
authors.affiliation: Division of Gastroenterology and Hepatology, Department of Medicine, The University of Hong Kong, Queen Mary Hospital, Hong Kong, China.
authors.forename: Danny Ka-Ho
authors.initials: DK
authors.lastname: Wong
authors.forename: Man-Fung
authors.initials: MF
authors.lastname: Yuen
authors.forename: HeJun
authors.initials: H
authors.lastname: Yuan
authors.forename: Simon Siu-Man
authors.initials: SS
authors.lastname: Sum
authors.forename: Chee-Kin
authors.initials: CK
authors.lastname: Hui
authors.forename: Jeff
authors.initials: J
authors.lastname: Hall
authors.forename: Ching-Lung
authors.initials: CL
authors.lastname: Lai
mesh_terms: D001483:Base Sequence; D004270:DNA, Circular / Q000032:analysis*; D004279:DNA, Viral / Q000032:analysis* / Q000097:blood; D006513:Hepatitis B e Antigens / Q000032:analysis*; D006515:Hepatitis B virus / Q000235:genetics*; D019694:Hepatitis B, Chronic / Q000821:virology*; D006801:Humans; D008969:Molecular Sequence Data
chemical_list: D004270:DNA, Circular; D004279:DNA, Viral; D006513:Hepatitis B e Antigens