Recombinant hemagglutinin of swine H۱N۱ influenza virus expression in the insect cells: Formulation in Montanide ISA۷۱ adjuvant and the potency studies

Objective(s): Influenza is a highly contagious disease, which affects the respiratory system and seasonal influenza is common throughout the world. Influenza vaccination is an effective way to reduce the risk of death and hospitalization. This study aims at the expression of swine recombinant hemagglutinin protein in the baculovirus expression system and it offers a comparison of the immunologic parameters with the commercial vaccine. Materials and Methods: The HA gene from the swine H۱N۱ strain of the Influenza virus was cloned into the Bac-To-Bac expression system in pFastBAC HTA vector and was transformed into Escherichia coli TOP۱۰ strain. After the confirmation, the vector was transfected into the SF۹ insect cell line. The recombinant HA was evaluated by SDS-PAGE and western blot. After formulation in Montanide ISA۷۱ adjuvant, the immunization test was performed comparatively with Alum adjuvant, commercial vaccine in four groups of BALB/c mice, of which one group was control without any vaccination. Two weeks after the last immunization, the antibody response was assessed with HI assay, and experimental mice were challenged with mouse-adapted Influenza A/PR۸/۳۴ (H۱N۱) virus through nasal inhalation. Results: The immunoassay results revealed that the candidate vaccine induced the antibody response as the commercial one did but it did not significantly reduce the mortality rate, body loss, and severe fever. Conclusion: To summarize, the results showed that the recombinant protein with the MontanideTM ISA- ۷۱ adjuvant developed a more appropriate level of immunity than Alum adjuvant, so it might be used as a safe and reliable vaccine against H۱N۱ virus for further research.

کلیدواژه ها:

Adjuvant ، H۱N۱ subtype ، Hemagglutinin ، Influenza ، Recombinant vaccine