Dna Vector In Pvax1-ires - And Replicative Dna Vector Psfvax1-ires Construction And Expression

The 21st century, the malignant tumor will become the first murderer which will threaten the human health. Along with the development of the molecular biology, the immunology as well as the gene technology, the tumor vaccine has become one kind of important treatment method for malignant tumor. In view of the superiority of the DNA vaccine which unfolds in the treatment of the malignant tumor, this research inserted the internal ribosome entry site (IRES ) into the eukaryotic expression vector (pVAX1), then a new DNA vaccine vector(pVAX1-IRES) was constructed. The experimental results showed that, in the vector pVAX1-IRES, the upstream and downstream of IRES sequence not only may separately express, also may simultaneously express two kinds of foreign genes. And this research further indicated that, in the vector pVAX1-IRES, the upstream of IRES could more efficiently express the foreign gene than the downstream.Because the semliki forest virus (SFV) could self-replicate, this research also inserted the duplication enzyme coding gene nsP1-4 into the vector pVAX1-IRES, then a kind of new replicative DNA vaccine vector was constructed. First, this new vector could simultaneously express two kinds of foreign genes; Second, because this new vector has duplication enzyme coding gene, so it can largely self-replicate in the cytoplasm, then the foreign genes could be efficiently expressed.The construction of the two new vectors offers a useful tool to study the new tumor vaccine.