[Antigenic properties of mutant hepatitis B virus surface antigen].
OBJECTIVE
To study the antigenic properties of mutant hepatitis B virus surface antigen, to understand the sensitivity of the commercially available HBsAg assays to the variants and to reduce the undetectability of the variants.


METHODS
Recombinant eukaryotic expression plasmids for HBsAg. The recombinant eukaryotic expression plasmids pSS1adr, pSS1adw2, pSS1adw2- 145Arg, pSS1adr-126 Asn and pSS1adr-126Ser were transfected into COS-7 cells. HBsAg in the supernatants of transfected cells was detected by using different commercial ELISA kits.


RESULTS
The absorbance value of pSS1adr-126 Asn and pSS1adr-126Ser plasmids were similar to that of the wild type HBsAg, the absorbance value of pSS1adw2-145Arg plasmids was lower than that of the wild type HBsAg.


CONCLUSIONS
It is estimated that the antigenicity of HBsAg mainly depended on the amino acid sequence of "a" antigen determinant and its conformation, so 145 amino acid substitutions led to the change of conformation and the antigenicity of variant HBsAg was lower than that of the wild type.
Guo
Min-zhuo
MZ
Beijing International Travel Healthcare Center, Beijing 100013, China.
Yi
Yao
Y
Chen
Si-yong
SY
Bai
Yu
Y
Jia
Zhi-yuan
ZY
Bi
Sheng-li
SL
D000818:Animals; D019556:COS Cells; D002522:Chlorocebus aethiops; D017077:Culture Media, Conditioned / Q000378:metabolism; D004797:Enzyme-Linked Immunosorbent Assay; D005822:Genetic Vectors / Q000235:genetics / Q000378:metabolism; D006514:Hepatitis B Surface Antigens / Q000032:analysis / Q000235:genetics* / Q000276:immunology*; D009154:Mutation; D014162:Transfection; D014759:Viral Envelope Proteins / Q000235:genetics
D017077:Culture Media, Conditioned; D006514:Hepatitis B Surface Antigens; C118669:S envelope protein, hepatitis B virus; D014759:Viral Envelope Proteins