Résumé
<p><b>OBJECTIVE</b>To increase the immune effect of gene vaccine, T7 RNA polymerase was used to establish a system of cytoplasmic expression.</p><p><b>METHODS</b>(1) The plasmid pT7 EMCVP1, including T7 promoter sequence, 5'-untranslated sequence of encephalomyocarditis (EMC) virus, VP1 sequence of coxsackievirus B3 (CVB3), was cotransfected with the plasmid pAR 3132, which codes for the T7 RNA polymerase, into HeLa cells and murine peritoneal macrophages. (2) The plasmid pT7 EMCVP1 and pAR 3132 were respectively transformed into the attenuated Salmonella typhimurium SL 7207. The two kinds of transformed bacteria were coinfected into murine peritoneal macrophages.</p><p><b>RESULTS</b>(1) The target antigen VP1 in the cytoplasm was about 2-4-fold higher than that of pcDNA3 VP1 singly transfected. (2) After the murine peritoneal macrophages were coinfected by two kinds of transformed bacteria, the target antigen VP1 could also be detected.</p><p><b>CONCLUSION</b>The pT7 EMCVP1 and pAR 3132 could be expressed in the cytoplasm of HeLa cells and murine peritoneal macrophages and the amount of the antigen VP1 increased remarkably as compared with that of pcDNA3 VP1 singly transfected.</p>