Objective      To construct a transgenic vector of human HLA-DRB1*0803 gene

and validate its expression and antigen-presenting function in vitro.       Methods      The cDNA encoding the HLA-DRB1*0803 gene was reverse transcribed and amplified by RT-PCR from the DRB1*0803 BLCL cell lines. The sequences of mouse Eα promoter and rabbit β-globin intron 1 were synthesized．The above 3 fragments were inserted into the plasmid pBR002-lacz

in a particular order. Successfully constructed pBR002-HLA-DRB1*0803 transgenic vector was used to transfect DCS cells and B cell line by Lipofectamine 2000

and the target proteins were detected by Western blotting and immunofluorescence assay. T cell proliferation assay were used to validate whether the transgenic DCS cells can present HBcAg antigens to human CD4

+

T cells and polarize the CD4

+

T cells.       Results      A pBR002-HLA-DRB1*0803 transgenic vector was successfully constructed

and verified by dual restriction enzyme and sanger sequencing. After transfection

the DCS cells and B cells expressed the target protein at a molecular weight of 29×10

3

. Immunofluorescence assay results showed that the HLA-DRB1 proteins were expressed mainly in the cytoplasm of DCS cells after transfection. T cell proliferation assay showed that the transfected DCS cells presented the HBcAg to the human T cells

resulting in a specific CD4

+

T cell response.       Conclusion      HLA-DRB1*0803 transgenic vector is successfully constructed

which can express the HLA-DRB1*0803 at the cellular level

present viral antigen and stimulate a HBcAg-specific CD4

+

T cell response.