Sequential change of the hypervariable region of the hepatitis C virus genome in acute infection.
Hepatitis C virus (HCV) infection is characterized by persistence of liver inflammation that often leads to end-stage liver disease, although the mechanisms are not fully understood. A hypervariable region (HVR) has been reported in the E2/NS1 region of the HCV genome, in which striking diversity is found among different HCV isolates. To investigate the association of the HVR alterations with the clinical courses of HCV infection, a longitudinal analysis of the HVR in patients with acute HCV infection was carried out. Plasma samples were obtained at several times in three patients with acute hepatitis C. Plasma RNA was extracted and reverse transcribed, and DNA fragments that included the HVR were amplified by PCR. The sequences of the HVR were directly determined from the PCR products by the dideoxy chain termination method, from which amino acid sequences were deduced. In all cases, plasma HCV-RNA disappeared with the improvement of the initial alanine aminotransferase (ALT) elevation, but HCV-RNA reappeared about 1 year later with or without deterioration of the hepatitis. In a case of sporadic acute hepatitis, the HCV in the recurrent phase had seven amino acid substitutions in the HVR compared with that in the acute phase, although no amino acid changes were noted during the initial acute phase. In a case of posttransfusion hepatitis, a marked difference was observed between the acute and the recurrent phases, with an amino acid homology of 30% (8/27). The mutation rate of the HVR had a tendency to accelerate as the HCV infection progressed to the chronic stage.(ABSTRACT TRUNCATED AT 250 WORDS)
Sakamoto
N
N
Second Department of Internal Medicine, Faculty of Medicine, Tokyo Medical and Dental University, Japan.
Enomoto
N
N
Kurosaki
M
M
Marumo
F
F
Sato
C
C
D000208:Acute Disease; D000410:Alanine Transaminase / Q000097:blood; D000595:Amino Acid Sequence; D000956:Antigens, Viral; D001483:Base Sequence; D002908:Chronic Disease; D005260:Female; D016679:Genome, Viral; D016174:Hepacivirus / Q000235:genetics* / Q000276:immunology; D006508:Hepatitis Antibodies / Q000276:immunology; D006526:Hepatitis C / Q000382:microbiology*; D018937:Hepatitis C Antibodies; D006801:Humans; D007135:Immunoglobulin Variable Region / Q000235:genetics*; D008875:Middle Aged; D008969:Molecular Sequence Data; D016133:Polymerase Chain Reaction; D012367:RNA, Viral / Q000097:blood; D017421:Sequence Analysis; D017386:Sequence Homology, Amino Acid; D017361:Viral Nonstructural Proteins / Q000276:immunology
D000956:Antigens, Viral; C064544:C100 protein, hepatitis C virus; D006508:Hepatitis Antibodies; D018937:Hepatitis C Antibodies; D007135:Immunoglobulin Variable Region; D012367:RNA, Viral; D017361:Viral Nonstructural Proteins; D000410:Alanine Transaminase