HPV16E7-HSP70 Hybrid DNA Vaccine Induces E7-Specific Cytotoxic T Cells and Antitumor Immunity

摘要

Using human papillomavirus type 16 (HPV16) E7 as an antigen and Heat Shock Protein 70 as adjuvant, we constructed a DNA vaccine by linking HSP70 gene to E7~(C91G) gene. Mice, after being immunized with E7~(C91G)-HSP70, E7~(C91G)/HSP70, E7~(C91G), andwild E7 DNA vaccines respectively, produced E7 specific CD8~+ T-cell precursor frequencies of 280.33 + 2.52, 144.34 + 4.04, 164.34 + 5.13 and 82.33 + 3.51 respectively within every 1 x 10~5 mouse splenocytes. This proves that E7~(C91G)-HSP70 fusion vaccine can significantly enhance the E7 specific cellular immunity within the mice body (p< 0.01). After being immunized with E7~(C91G)-HSP70 fusion vaccine, tumor-bearing mice of the group being treated have significantly longer latency and survival periods, comparing with other three categories of E7 vaccines. Experiment shows that this vaccine has a significant effect on enhancing E7 positive tumor-treatment within mice body. After being immunized with E7~(C91G)-HSP70 vaccine, there were no pathologicalchanges found in livers, kidneys and spleens of the mice, which proves that the vaccine is quite safe. After all, E7~(C91G)-HSP70 fusion vaccine has a much stronger tumor- treatment effect than that of wild type E7 DNA vaccine.