Coexistence of hepatitis B surface antigen and anti-HBs in Chinese chronic hepatitis B virus patients relating to genotype C and mutations in the S and P gene reverse transcriptase region.
We aimed to determine the prevalence of the coexistence of HBsAg and anti-HBs and to analyze the clinical and virological features of infection, including amino acid (aa) patterns of the S gene and reverse transcriptase (RT) region in Chinese chronic hepatitis B (CHB) patients. Fifty-four (2.90%) CHB patients who were positive for both HBsAg and anti-HBs were tested, and sequences were obtained from 52 of them as well as 48 patients from a control group. S gene and RT region sequences were amplified and sequenced using in-house protocols. There was no significant difference between patients with and without anti-HBs with regard to age, gender, alanine aminotransferase level, and the proportion positive for HBeAg and HBcAb. The occurrence of genotype C (P = 0.001) and anti-HBeAb positivity (P = 0.027) was significantly higher in HBsAg+/anti-HBs+ individuals. In the S gene, the number of mutated residues in the HBsAg+/anti-HBs+ group was markedly higher than in control patients (1.88 versus 1.02 substitutions per 100 amino acids, P = 0.022). The amino acid exchange occurred mostly within the N-terminal region (2.15 versus 0.87 substitutions per 100 amino acids, P = 0.023) and the "a" determinant (3.61 versus 1.56 substitutions per 100 amino acids, P = 0.049) in the two groups. In the RT region, the mean number of substitution per 100 aa showed a tendency to be significantly higher in HBsAg+/anti-HBs+ patients than in controls (2.34 versus 1.46, P = 0.040). This study showed a prevalence of coexistence of anti-HBs in HBsAg-positive patients and an increased frequency of genotype C and aa variability within both HBsAg and RT involving functionally important regions of those proteins.
Department of Laboratory Medicine, Huashan Hospital, Shanghai Medical College, Fudan University, Shanghai, 200040, China.
Weiwei
W
Liu
Tingting
T
Hu
Xinyu
X
Wang
Yuming
Y
Chen
Minying
M
Huang
Chao
C
Yuan
Ming
M
Guan
D000293:Adolescent; D000328:Adult; D000368:Aged; D019943:Amino Acid Substitution; D002681:China; D004279:DNA, Viral / Q000737:chemistry / Q000235:genetics; D005260:Female; D015684:Gene Products, pol / Q000235:genetics* / Q000276:immunology; D005838:Genotype; D006510:Hepatitis B Antibodies / Q000097:blood / Q000276:immunology*; D006514:Hepatitis B Surface Antigens / Q000097:blood / Q000276:immunology*; D006515:Hepatitis B virus / Q000254:growth & development / Q000276:immunology*; D019694:Hepatitis B, Chronic / Q000276:immunology* / Q000821:virology*; D006801:Humans; D008297:Male; D008875:Middle Aged; D020125:Mutation, Missense; D017422:Sequence Analysis, DNA; D014759:Viral Envelope Proteins / Q000235:genetics* / Q000276:immunology; D055815:Young Adult
D004279:DNA, Viral; D015684:Gene Products, pol; D006510:Hepatitis B Antibodies; D006514:Hepatitis B Surface Antigens; C066027:P protein, Hepatitis B virus; C118669:S envelope protein, hepatitis B virus; D014759:Viral Envelope Proteins