Immunogenicity of a new recombinant IpaC from shigella dysenteriae type I in guinea pig as a vaccine candidate

Recombinant vaccine technology is one of the most developed means in controlling infectious diseases. However, an effective vaccine against Shigella is still missing. To evaluate recombinant IpaC protein of Shigella as a vaccine candidate. In this study we cloned IpaC gene into an expression vector in prokaryotic system. The protein expression was evaluated by SDS-PAGE and Western-Blotting analysis. The recombinant protein was purified using Ni-NTA affinity chromatography. Guinea pigs were immunized with the recombinant protein and the level of immunogenicity was examined by ELISA and Western blotting of IpaC. Challenge test was done through the intraoculary injection of Shigella dysenteriae [6×108 CFU/eye] and after 48 hours was scored for keratoconjunctivitis. The results showed a remarkable level of immunogenicity in terms of antibody response and protection against keratoconjunctivitis in tested animals. The recombinant IpaC protein provided a protective system against Shigella dysenteriae type I during the challenge test. The results showed the potential of using recombinant IpaC in preparation of vaccine in perspective studies

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

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. 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. 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. 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