Dendritic Cells Vaccines Targeting Aspartate-b-hydroxylase Gene Induce Specific T Lymphocytes Against Hepatocellular Carcinoma And Related Mechanisms

Objective:To explore the antitumor effect and related mechanisms of specific cytotoxicity T lymphocytes(CTLs)induced by dendritic cells(DCs)vaccine targeting aspartatecells-P-hydroxylase(AAH)gene against hepatocellular carcinoma SMMC-7721 in vitro and in vivo.Methods:Mice bone marrow-derived DCs were infected by recombinant adenovirus vector encoding AAH gene to construct specific AAH-DCs vaccine.C57BL/6 mice were immunized by the vaccine,the cytotoxic effect of CTLs against SMMC-7721 cells was observed by lactate dehydrogenase(LDH)release assay.Subcutaneous xenograft nude mice model were constructed,and were treated with specific CTLs induced by AAH-DCs vaccine.Mice were sacrificed on day 21 after tumor challenge.The levels of Caspase3,Bax,Bcl-2 mRNA and protein were detected by real-time PCR and Western blot,respectively.Moreover,the expression of CD3+ T cells in nude mice spleen was measured by immunohistochemical staining.Results:AAH-loaded DCs vaccine was successfully constructed.LDH release assay showed that CTLs response induced by AAH-DCs vaccine played a striking killing cell effect on SMMC-7721 cells.Obvious declined mean tumor volume of AAH-DCs-CTLs group was observed compared with other groups(P<0.05).The increased expressions of Caspase3 and Bax while decreased expression of Bcl-2 in AAH-DCs-CTLs group were tested.The numbers of CD3+ T cells in nude mice spleen of AAH-DCs-CTLs group were more than those in GFP-DCs-CTLs group(P<0.05).Conclusion:CTLs induced by DCs harboring recombinant human AAH gene could generate a lysis effect on SMMC-7721 cells in vitro,and prevent the growth of subcutaneous xenograft hepatoma in nude mice via promoting apoptosis.