ABSTRACT
<p><b>OBJECTIVE</b>Dendritic cell vaccines are one of the important active immunotherapies for neoplasms. The aim of this study was to observe the killing effect of specific cytotoxic T lymphocytes (CTL) on liver carcinoma HepG2 and SMMC-7721 cells in vitro. The CTL was induced by human peripheral blood mononuclear cells-originated dendritic cells (DC) transfected by recombinant adeno-associated virus (rAAV) with hAFP gene fragment (137-145).</p><p><b>METHODS</b>Immature DCs were generated from peripheral blood mononuclear cells of healthy volunteers and then transfected by rAAV with AFP gene fragment. The CTL was thereafter induced. The activities of DC and CTL were measured and the killing effect of the CTL on HepG2 cells was detected using M1Tr assay.</p><p><b>RESULTS</b>The mature DC, transfected or not, highly expressed CD40, CD86 and IL-12. IFN-gamma was highly expressed in the CTL. The DC-induced CTL could effectively recognize and destroy the HepG2 and SMMC-7721 cells.</p><p><b>CONCLUSION</b>DC transfected by rAAV can stimulate the proliferation and differentiation of lymphocytes and also induce the proliferation of CTL, and their own phenotypes are not significantly altered. The DC vaccine can be effectively used as an adjuvant immunotherapy for patients with hepatocellular carcinoma.</p>
Subject(s)
Humans , B7-2 Antigen , Metabolism , CD40 Antigens , Metabolism , Cancer Vaccines , Allergy and Immunology , Carcinoma, Hepatocellular , Pathology , Cell Differentiation , Cell Line, Tumor , Cell Proliferation , Cytotoxicity, Immunologic , Dendritic Cells , Cell Biology , Allergy and Immunology , Metabolism , Dependovirus , Genetics , Hep G2 Cells , Interferon-gamma , Metabolism , Interleukin-12 , Metabolism , Liver Neoplasms , Pathology , Peptide Fragments , Genetics , T-Lymphocytes, Cytotoxic , Allergy and Immunology , Metabolism , Pathology , Transfection , alpha-Fetoproteins , GeneticsABSTRACT
<p><b>OBJECTIVES</b>To compare the in vitro killing effects of cytotoxic T lymphocytes (CTLs) induced by dendritic cells(DCs) that modified with 4 different specific hAFP-derived peptides.</p><p><b>METHODS</b>DCs derived from normal human peripheral monocytes were activated by GM-CSF and IL-4. MTT assay was applied to analyse the proliferation activities of the DCs. To induce the specific CTLs, DCs modified with four immunodominant epitopes from alpha fetoprotein (AFP) were cocultured with MNC derived CD8+ lymphocytes. The acquired specific CTLs were cocultured with SMMC-7721 cells at different dilutions, and the killing effects were detected by flow-cytometry and Non-Radioactive Cytotoxity kit.</p><p><b>RESULTS</b>The CTLs stimulated by DCs modified with the four immunodominant epitopes from alpha fetoprotein (AFP) had specific killing activities on the SMMC-7721 cells. And statistical differences of the killing effects existed between the hAFP(158-166) (FMNKFIYEI) group and the other three groups.</p><p><b>CONCLUSION</b>CTLs induced by the DCs modified with the four immunodominant peptides had significant killing effects on the hepatocellular cancer cells in vitro. The hAFP(158-166) (FMNKFIYEI) peptide had a relatively higher efficiency in inducing DCs and stimulating specific CTLs.</p>