Anionic and Cationic Lipid Adjuvants individually induce distinct adaptive Th1/Th2-type immunity in enhancing post-intranasal immunization response against influenza

Abstract

Abstract At this time when vaccine development is at its peak against different respiratory diseases, it is of utmost importance to find suitable adjuvants that can increase the potency of the vaccine candidates. In this study, we have shown how anionic and cationic lipid adjuvants can differ in their mechanism to induce immune protection against influenza. In presence of Hemagglutinin (HA) antigen, the anionic adjuvant (L3) induces enhanced dendritic cell activity, CD80, and CD86 costimulatory marker expression, MHCII, and DEC205 expression, and T cell activation. On the contrary, the cationic adjuvant (N3) induces MHCI expression on dendritic cells along with the higher Th17 cell population and enhanced CD28 expression and activation of CD8T cells. They exhibited significantly higher interferon-gamma (IFNγ) within both CD4T and CD8T cells. L3 treated groups produce significantly higher B plasma cells and higher titers of anti-HA IgG and IgA with more neutralization capacity of the live virus than the N3 groups. Thus, in this study, we illustrate how the use of differentially charged lipid adjuvants in combination with influenza HA antigen, drives differential adaptive immune response patterns. While anionic adjuvants are inducing better humoral response than cationic adjuvants, the latter influence significantly higher cell-mediated immunity. This will pave the way forward in the selection of the adjuvants in the future development of vaccine formulation targeting specific groups of individuals having a deficit in one or the other arm of adaptive immunity.