prevention and inhibition of tc-1 cell growth in tumor bearing mice by hpv16 e7 protein in fusion with shiga toxin b-subunit from shigella dysenteriae

objective: for immunotherapy of human papillomavirus (hpv) -16-associated cervical cancers the e7 protein is considered a prime candidate. however it is a poor inducer of cytotoxic t-cell response, when being used as a singular antigen in protein vaccination. hence, in this study we focused on the utilization of a vaccine delivery system for prevention or treatment of cervical cancer. materials and methods: in this experimental study, we designed and evaluated a novel fusion protein comprising hpv16 e7 antigen fused to shiga toxin b-subunit (stxb) as both an antigen vector and an adjuvant. then we designed two preventive and therapeutic tumor models to investigate the prevention and inhibition of tc-1 cell growth in female c57bl/6 mice, respectively. in each model, mice were immunized with the recombinant protein of e7-stxb or e7 without any adjuvant. results: we demonstrated that prophylactic immunization of e7-stxb protected mice against tc-1 cells. also in the therapeutic model, e7-stxb inhibited tc-1 tumor growth inlungs. the results were significant when compared with the immunization of e7 singularly. conclusion: we concluded that immunization with the e7-stxb protein without any adjuvant could generate anti-tumor effect in mice challenged with tc-1 cells.this research verifies the clinical applications and the future prospects of developing hpv16 e7 therapeutic vaccines fused to immunoadjuvants.