Analysis of hepatitis A virus protein 2B in sera of hepatitis A of various severities.
BACKGROUND
In our recent study of the full-length hepatitis A virus (HAV) genome from some patients with fulminant hepatitis and acute hepatitis, possible associations were suggested between the severity of hepatitis A and the amino acid substitutions in the nonstructural protein 2B. We therefore analyzed HAV 2B from many patients with various clinical disease severities.


METHODS
Serum samples from 30 Japanese patients with sporadic hepatitis A from five widely separated regions of Japan, comprising nine patients with fulminant hepatitis (FH), six with severe acute hepatitis (AHs), and 15 with acute hepatitis (AH), were examined for HAV RNA. The entire sequences of HAV 2B were analyzed.


RESULTS
Compared with the sequence of the wild-type HAV strain GBM, nucleotide sequences of 2B had homology of 94.5 +/- 1.0% in FH, 95.2 +/- 1.2% in AHs, and 95.1 +/- 1.8% in AH. Deduced amino acid sequences had homology of 97.5 +/- 2.1% in FH, 97.9 +/- 2.4% in AHs, and 98.5 +/- 1.3% in AH. Differences were not statistically significant among the three groups. The average number of amino acid mutations between amino acids 100 and 200 was 5.0 +/- 5.2 per case in FH, 4.0 +/- 6.0 in AHs, and 1.9 +/- 2.9 in AH. The differences between FH and AH, AHs and AH, and between severe cases (FH and AHs) and nonsevere cases (AH) were not statistically significant (P = 0.13, P = 0.45, and P = 0.10, respectively).


CONCLUSIONS
There were no obvious differences in the sequences among FH, AHs, and AH throughout the 2B region, but there seemed to be more mutations in the strains obtained from FH and AHs patients than in those obtained from AH patients in the central part of HAV 2B.
Fujiwara
Keiichi
K
Department of Medicine and Clinical Oncology, Graduate School of Medicine, Chiba University, 1-8-1 Inohana, Chuo-ku, Chiba 260-8670, Japan.
Yokosuka
Osamu
O
Imazeki
Fumio
F
Miki
Makoto
M
Suzuki
Kazuyuki
K
Okita
Kiwamu
K
Tanaka
Eiji
E
Omata
Masao
M
D000208:Acute Disease; D000328:Adult; D000595:Amino Acid Sequence; D019943:Amino Acid Substitution; D044466:Asian People; D001483:Base Sequence; D005260:Female; D005838:Genotype; D006506:Hepatitis A / Q000097:blood / Q000145:classification / Q000235:genetics* / Q000503:physiopathology; D017957:Hepatitis A Virus, Human / Q000235:genetics*; D006801:Humans; D007564:Japan; D008297:Male; D008875:Middle Aged; D009154:Mutation / Q000235:genetics*; D012367:RNA, Viral; D017423:Sequence Analysis, RNA; D012720:Severity of Illness Index; D017361:Viral Nonstructural Proteins / Q000235:genetics*
C116507:2B protein, hepatitis A virus; D012367:RNA, Viral; D017361:Viral Nonstructural Proteins