MULTIVALENT QS-18 PROTEIN NANOPARTICLES FOR A BROADLY PROTECTIVE INFLUENZA VIRUS VACCINE

The COVID-19 pandemic has underscored the importance of not only vaccines but also vaccine adjuvants. Plant saponins have yielded some of the most powerful vaccine adjuvants to date. This project seeks to combine and develop QS-18, a commercially viable and highly abundant saponin, with spontaneous nanoliposome antigen particlization technology based on cobalt porphyrin-phospholipid (CoPoP), which has demonstrated its clinical application and entered Phase III clinical trials. Influenza will be used as a model disease to study the advantages of QS-18. The project will provide pilot data necessary to clinical translation focused on toxicity (mouse and rabbits) and efficacy (mouse and ferrets) through the following objectives: (1) Produce and procure well-characterized CoPoP/QS-18 liposomes, displaying influenza hemagglutinin (HA) and neuraminidase (NA) antigens; (2) Characterize concentration of components of CoPoP/QS-18 liposomes; (3) Determine storage stability of components of CoPoP/QS-18 liposomes; (4) Determine pilot toxicity of CoPoP/QS-18 liposomes and CoPoP/QS-21 liposomes; (5) Compare CoPoP/QS-18 to CoPoP/QS-21 for inducing antigen-specific antibodies and antigen specific cellular responses following mouse immunization; (6) Assess how CoPoP/QS-18 induces protective immune responses in a mouse challenge using mouse adapted H1, H3, and B influenza virus strains; (7) Assess protection from influenza virus challenge in ferrets.