Electroporation-mediated DNA Coding For EGFRvⅢ Immunize The Mice Against Intracerebral Tumor

DNA vaccines coding for tumor specific antigen protein gene not only induce specific CD8+ T cells with antitumor activity in vivo, but also induce humoral immunity, turning it into perfect for anti-tumor immunity. For intracerebral tumor, DNA vaccine coding for with tumor specific antigen with less autoimmune can precisely excise the tumor cells which express the specific antigen. However, naked DNA vaccines with faint effect need some another vehicle or physical transport way to increase the immunological effect. Electroporation is the most effective physical approach to convey DNA. It cannot only improve the effect of the transfer of the DNA plasmid in vivo, but also the immunological effect of the vaccine.Epidermal growth factor receptor variant Ⅲ, a kind of tumor specific antigen, is one of the most common variant antigens in the glioma. In our research, we constructed the DNA plasmid coding for the EGFRvⅢ, and then verified the abilities of immune induction and inhibition of EGFRvⅢ-expressing tumor formation and growth with electroporation-mediated DNA vaccines. First, we cloned and constructed the DNA plasmid with EGFRvⅢ gene, and selected the B16F10 cell expressing the EGFRvⅢ(B16F10-EGFRvIII) which transferred the DNA by liposome. We made the confirmation by western blotting and cell immunochemistry. Then we used the electroporation-mediated DNA vaccine to immunize the mice and detect CTL activity. At last, we verified the growth and inhibitory effect of vaccinated mice with the subcutaneous tumor and intracerebral tumor.The results showed that we constructed DNA with high efficient expressing the EGFRvⅢ, and cell with stability-expressing this protein which can rightly express and locate. Compared with the group without vaccinated, the group with electroporation-mediated DNA vaccine can induce much higher activity of CTL(p <0.05), and the inhibition of the growth of the subcutaneous tumor and intracerebral tumor more obvious(s.c., p=0.002, i.c., p=0.02). Therefore, electroporation mediated DNA immunization is expected for the immunotherapy of intracerebral tumors and significantly inhibit the growth of brain tumors.