Flt3L and GM-CSF enhance anti-tumor effect of HPV16/18 vaccine via increasing immune response.

OBJECTIVES Cervical cancer is the second leading cause of cancer death in women, which is closely related to persistent infection with high-risk Human papillomavirus (HPV). Therefore, it is important to develop new adjuvants for HPV vaccines. This research aimed to establish two new adjuvants which can enhance the immune effect of vaccines. MATERIALS AND METHODS C57BL/6 mice were divided into 5 groups and immunized by intramuscular injection of plasmid once every 2 weeks, three times in all. The growth and metastasis of tumors in mice was observed by in vivo imaging system (IVIS). Then, the mice were sacrificed and the pathological changes of organs were observed. In addition, the lymphocyte suspension was used for CLT killing test. IFN-γ level and the number of splenocytes which secrete IFN-γ were detected. Additionally, the specific antibody level of HPV16/18 E6 E7 L1 L2 was also detected. RESULTS The constructed nucleic acid vaccines had no significant effect on both the physiological and biochemical indexes, while it significantly increased the survival period and survival rate of mice. Flt3L and GM-CSF enhanced the immune effect of HPV16/18 vaccine via increasing the specific antibodies and IFN-γ cytokines. CONCLUSIONS These data suggested that Flt3L and GM-CSF enhanced the anti-tumor effect of vaccines via increasing immune response. Thereby, our findings may hope to provide new perspective for the treatment of cervical cancer.