BACKGROUND
Direct genotyping of hepatitis B virus (HBV) in samples from patients with hepatitis delta can be impossible due to the undetectable concentration of HBV DNA. A sufficient amount of surface HBV protein (HBsAg) in such samples makes it possible to determine HBV genotype using enzyme-linked immunosorbent assay (ELISA) of this antigen with a panel of monoclonal antibodies (MAB).
PURPOSE
To compare the results of HBV genotyping using the in-house MAB panel with the results of molecular analysis of samples from patients with chronic hepatitis B (CHB) and to determine HBV genotypes in samples from patients with hepatitis delta.
MATERIAL AND METHODS
Total 122 serum samples from CHB patients from Yakutia and 211 serum samples from hepatitis delta patients from Yakutia (12 samples) and Tuva (199 samples) were collected. HBV serotypes/genotypes were determined by ELISA using the developed reagents. Molecular methods included the isolation of HBV DNA, amplification of the S gene region (713 nt), phylogenetic analysis of the nucleotide sequences.
RESULTS
In a group of samples from CHB patients positive for HBV DNA (86 samples) 95% (82/86) valid results were obtained using our MAB kit. The following genotypes were identified: A — 32 (39%), C — 3 (4%), D — 47 (57%). The results of HBV genotyping using two methods were identical for 81/82 (99%) samples. HBV genotyping using developed reagents gave 96.2% (203/211) of valid results in samples from patients with hepatitis delta compared to 3.8% obtained using standard molecular technic (p<0.001). Following HBV genotypes were identified: A — 17 samples (8.4%) and D — 186 samples (91.6%).
CONCLUSIONS
The developed test with MAB panel is able to reliably determine HBV genotype and has advantages over standard molecular methods for HBV genotyping in patients with hepatitis delta.