[Preparation of anti HBs monoclonal antibody and its combination characterization to both wild-type HBsAg and immune escape mutant HBsAg].

AIM

To prepare monoclonal antibodies against HBsAg and estimate its binding capacity to both wild-type and varies of immune escape mutant-type HBsAg.

METHODS

Using self-made the anti-HBs G6 mAb and HRP-labeled goat anti-HBs antibody, A sandwich ELISA for detection both wild-type and varies of immune escape mutant-type HBsAg has been developed. Applying this assay, to detect 17 species of whole gene wild-type and recombination expressed HBsAg which varied in "a" determinant. to evaluate its clinical application characteristic of this assay, we used the other commercial reagents to Comparing with it.

RESULTS

One strain hybridoma cell lin secreted anti-HBs mAb (defined G6), was obtained. It grew stably and the titers of the culture supernatant and hydroperitoneum were 2 048 and 4 096x10(3). The sensitivity to the wild-type HBsAg of this assay was less than 0.125 microg/L. This anti-HBs mAb can bind with 12 in 15 species mutant HBsAg (P/N> or =2.5), and 2 of them were low absorbent value at 450 nm(A(450)) group which was 7.55 percent of the wild-type, 1 of them was middle A(450) value group which was 59.40 percent of the wild-type, 9 of them were high A(450) value group which was 92.1-109.4 percent of the wild-type. The low A(450) value group and the negative group were diversified in 120-124 basyl in I loop of the HBV "a" determinant. We also used other commercial reagents, which was widely used in clinic, to detect partial species mutant HBsAg, the average A(450) value was less than foregoing assay.

CONCLUSION

The G6 anti-HBs mAb was able to bind most of the immune escape mutant HBsAg in the test. And there would be some special regulations between the mutant site and the recombination expressed HBsAg binding capability.