[Study on the mechanism of HLA-I-expressing regulation caused by the core region mutation of HBV adr subtype].
OBJECTIVE
To study the influence and mechanism of HBV core region mutation on HLA-I expression.


METHODS
Eukaryotic expression vectors of HBV core region mutations L97, G87 and V60 were constructed and transfected into HepG2 cells. Then the expressions of HLA-I were detected by RT-PCR and Western blot. The mRNA of antigen-presentation-associated genes, including LMP2, TAP1 and tapasin, were measured using RT-PCR.


RESULTS
Different levels of HBsAg in the supernatants of transfected cells were detected by ELISA. The HBsAg of the mutated groups was markedly higher than that of the wild ones. All the transfected cells expressed HLA-I molecules, especially the L97 group. It was also found that the mRNA of TAP1 gene was up-regulated, while the mRNA of LMP and tapasin genes had no changes.


CONCLUSIONS
The core region mutation of HBV can lower the expression of HBsAg; mutated groups and wild ones both can increase the expression of HLA-I molecules. The up-regulation of TAP1 gene expression might be the cause of these changes.
Wang
Jiu-ping
JP
Center of Diagnosis and Treatment for Infectious Diseases, Tangdu Hospital, Fourth Military Medical University, Xi'an 710038, China.
Wang
Ping-zhong
PZ
Li
Jun
J
Pan
Lei
L
Zhang
Ying
Y
Li
Xin-hong
XH
Wang
Lin-xu
LX
Chen
Wei-hong
WH
D000071181:ATP Binding Cassette Transporter, Subfamily B, Member 2; D018528:ATP-Binding Cassette Transporters / Q000378:metabolism; D015967:Gene Expression Regulation, Viral; D056945:Hep G2 Cells; D006514:Hepatitis B Surface Antigens / Q000378:metabolism; D006515:Hepatitis B virus / Q000235:genetics*; D015395:Histocompatibility Antigens Class I / Q000235:genetics / Q000378:metabolism*; D006801:Humans; D009154:Mutation
D000071181:ATP Binding Cassette Transporter, Subfamily B, Member 2; D018528:ATP-Binding Cassette Transporters; D006514:Hepatitis B Surface Antigens; D015395:Histocompatibility Antigens Class I; C073119:TAP1 protein, human