Objective:To investigate the killing effect of cytotoxic T lymphocytes(CTLs)on hepatocellular carcinoma cells line SMMC-7721 after being induced by dendritic cells(DCs)transfected with human aspartate-β-hydroxylase gene in vitro. Methods:Immature dendritic cells

from the bone marrow of the mice C57BL/6

loaded with human aspartate-β-hydroxylase recombinant adenovirus were used to prepare for DCs vaccine. They were classified as immature dendritic cells infected by recombinant adenovirus loaded with human aspartate-β-hydroxylase(DCs-ASPH group)

immature dendritic cells infected by recombinant adenovirus(DCs-GFP group)and immature dendritic cells group(im DCs group). The expressions of ASPH protein and m RNA in each DCs were detected by Western blot and q RT-PCR

and the surface expression of CD80

MHC-Ⅱ and CD11 c were examined by flow cytometry(FCM)in both uninfected and infected dendritic cells. The specific CTLs induced by DCs vaccine were subsequently co-cultured with hepatocellular carcinoma cells line SMMC-7721. The proliferation and apoptosis rate of SMMC-7721 cells were detected by cell counting kit 8(CCK-8)and flow cytometry. The level of IFN-γ was measured by enzyme-linked immunosorbent assay(ELISA). Results:DCs was successfully cultured and DCs vaccine was constructed. The DCs loaded with human aspartate-β-hydroxylase recombinant adenovirus expressed significantly higher level of CD80(P=0.000)

MHC-Ⅱ(P=0.000)and CD11c(P=0.000)than those in DCsGFP group and im DCs group. The proliferation of SMMC-7721 cells co-cultured with CTLs induced by human aspartate-β-hydroxylase recombinant adenovirus was lower while the apoptosis rate was higher than those in DCs-GFP group and im DCs group(P=0.000).The secretion level of IFN-γ in CTLs induced by DCs-ASPH was also significantly higher than that in DCs-GFP group and im DCs group(P=0.000). Conclusion:CTLs induced by DCs transfected with human aspartate-β-hydroxylase recombinant adenovirus can apparently inhibit the proliferation of hepatocellular carcinoma cells line SMMC-7721

and induce cells apoptosis in vitro.