Vaccine formulation of an activator of the stimulator of interferon genes (STING) pathway and saponin adjuvant for enhanced protection of aged population.
There is an urgent need to improve protective responses to vaccination in the elderly population, which is at especially high risk for adverse outcomes from infection. cGAMP acts as an agonist of STING (Stimulator of Interferon Genes) and induces type I IFN responses which are important for development of immunity. When delivered with influenza vaccine, it potentiated and prolonged cellular and humoral immune responses to the vaccine. Since STING is located inside cells on the endoplasmic reticulum, cGAMP is not easily transported intracellularly. Delivering cGAMP in the presence of saponin improved its availability to STING and combined adjuvanted potential of both compounds.
Emory researchers have formulated a combination of cGAMP and saponin adjuvants. Saponin adjuvants, such as Quil-A or QS-21, are a category of adjuvants that have been used. This invention provides vaccine adjuvanted with cGAMP-saponin combination to increase the protective efficacy in elderly patients who are at a higher risk of disease and mortality. Researchers have demonstrated that aged mice vaccinated against influenza with the combination of cGAMP and saponin achieved enhanced protection against influenza and virtually all of them survived the lethal influenza challenge.
In vitro and mouse model study data are available.
Publication: Vasilieva, E. V. et al. (2019). Front. Immunol., 10, 3006.