RESUMO
AIM: To prepare the vaccine of DCs(pcDNA3-hCEA) and observ the immunity effect of the DCs(pcDNA3-hCEA) inoculating on CT26(hCEA +) loaded in BALB/c mice. METHODS: DCs were generated from bone marrow in the presence of rmGM-CSF and rmIL-4. A new recombinant plasmid, pcDNA3-hCEA, reformed with inserting a 2.4 kb human CEA cDNA into pcDNA3. DC vaccine was prepared by transfection with pcDNA3-hCEA using lipofectamine. CEA mRNA expressed in DCs(pcDNA3-hCEA) was confirmed by RT-PCR, CEA expression level was detected with RIA method, and CEA specific CTL was induced in vitro . After vaccination of DCs(pcDNA3-hCEA), the survival time of the BALB/c mice challenged with critical loading CT26(hCEA +) was observed. RESULTS: G418 test showed that about 14% DCs were transfected with pcDNA3-hCEA. And CEA mRNA and protein could be detected respectively by RT-PCR and RIA in the genetically modified DCs. Furthermore, the DCs coud be targeted by specific CTL, the survival time of the mice challenged with CT26(hCEA +) was prolonged 1-4 weeks. CONCLUSION: These results demonstrate that specific antitumor immune responses could be induced efficiently by vaccination of DCs(pcDNA3-hCEA), which is transfected eukaryotic expression vector encoding tumor antigen gene.