JVRS-100 adjuvanted universal influenza A vaccine based on a multiple antigenic peptide of M2e protects from lethal challenge (132.6)

Abstract

Abstract Background: The conventional vaccine strategy for control of influenza A is vulnerable to antigenic drift and the emergence of unmatched epidemic strains that cause primary vaccine failure. A vaccine strategy that targets an influenza antigen, which is less susceptible to antigenic variation, would be a major improvement. Methods: Balb/c mice were vaccinated three times with the M2e peptide in the context of a multiple antigenic peptide (MAP) complex and combination with the cationic lipid DNA complex adjuvant (JVRS-100). Antibody titers were monitored over the time course of vaccination and the mice received a lethal challenge with H1N1 (PR/8/34) or H3N2 (HKx31) two weeks after the final vaccination. Results: Vaccination of mice with JVRS-100-MAP4-M2e compared to MAP4-M2e resulted in increased survival following lethal challenge with 6x LD50 PR/8/34 H1N1 (100% vs. 30%, P=0.002) or 10x LD50 HKx31 H3N2 (80% vs. 20%). Recipients of 200µl serum from MAP-4-M2e/JVRS-100 vaccinated mice and challenged with H1N1 (6x LD50 PR/8/34) resulted in survival of 60% (P=0.014) compared with control mice which received 200µl naive serum (0% survival). Furthermore, recipients of 300µl serum from MAP-4-M2e/JVRS-100 vaccinated mice and challenged with H1N1 (2x LD50 PR/8/34) resulted in survival of 100% (P=0.0026) compared with control mice which received 200µl naive serum (0% survival). Conclusion: These studies demonstrate that a simple, synthetic M2e vaccine in a MAP configuration with a strong adjuvant may result in a viable vaccine candidate for universal flu vaccination and the protective immunity is primarily due to an antibody response.