Antitumor Response to a Codon-Optimized HPV-16 E7/HSP70 Fusion Antigen DNA Vaccine

Vaccines based on virus-like particles are effective against Human Papilloma Virus (HPV) infection; however, they have not shown a therapeutic effect against HPV-associated diseases. New immunotherapy strategies based on immune responses against tumor antigens can positively affect the clearance of HPV-associated lesions.
To generate two therapeutic fusion DNA vaccines (optimizedE7/mouseHSP70 and wildE7/mouseHSP70) to induce antitumor specific responses in mice models.
Mice were immunized with recombinant DNA vaccines. The splenocytes of immunized mice were collected and lactate dehydrogenase and IFN-γ productions were measured after three injections in order to evaluate cytotoxic T lymphocytes (CTLs) activity. MTT assay was carried out for lymphocyte stimulation.
The fusion DNA vaccines, specifically uE7-HSP70, elicited varying levels of IFN-γ and CTLs responses compared to the control group (P It is concluded that our fusion DNA vaccines considerably enhanced specific cellular responses against HPV tumor model. In addition, optimized E7 showed a notable immunogenicity and inhibitory effect on the reduction of tumor size.