iBioModulator can dramatically improve vaccine performance
iBioModulator improves effectiveness of a vaccine against HPV16
The E7 transforming gene of human papilloma virus has been implicated in the maintenance of HPV in keratinous tissues and their oncogenic transformation in cervical cancers. Fusions of E7 and a less-transforming mutant form (E7GGG) were made in the lichenase surface loop and compared with native, unfused E7 and E7GGG as vaccines. Since there is no cell culture or animal model of HPV infection, E7-transformed mouse TC-1 cells serve as a surrogate tumor model for HPV infections and cancers.
Vaccines (+/-adjuvant) were evaluated for their ability to prevent implantation and growth of TC-1 tumors (prophylaxis), and for their ability to induce immunity that reduces existing TC-1 tumors and extends survival.
Fusion of iBiomodulator with the E7GGG or E7 antigens completely prevented the establishment of E7 expressing TC-1 cell tumors in mice, showing that an effective prophylactic vaccine for HPV-16 can be produced in plants. In addition, the E7 antigens fused to ibioModulator completely protected mice from prior administration of HPV tumorigenic cells, indicating that therapeutic vaccination could provide a treatment option for already-established cervical tumors. In both prophylactic and therapeutic mode, E7 antigens administered without being fused to iBioModulator failed to completely protect the mice from tumors and tumor-related death.
iBioModulator improves antibody titers and extends protection in vaccines
In a transmission-blocking vaccine for malaria, fusion of iBioModulator with the Pfs25 antigen of Plasmodium falciparum resulted in a 10-fold increase in antigen-specific IgG when compared to native (unfused) Pfs25. In addition, in the standard oocyte membrane-feeding assay for transmission blocking antibodies, fusion of Pfs25 with iBioModulator reduced the dose of vaccine required for complete transmission-blocking activity five-fold, and provided longer protection after immunization.