Intranasal Coronavirus SARS-CoV-2 Immunization with Lipid Adjuvants Provides Systemic and Mucosal Immune Response against SARS-CoV-2 S1 Spike and Nucleocapsid Protein

In this preclinical two-dose mucosal immunization study, using a combination of S1 spike and nucleocapsid proteins with cationic (N3)/or anionic (L3) lipids were investigated using an intranasal delivery route. The study showed that nasal administration of low amounts of antigens/adjuvants induced a primary and secondary immune response in systemic IgG, mIL-5, and IFN-gamma secreting T lymphocytes, as well as humoral IgA in nasal and intestinal mucosal compartments. It is believed that recipients will benefit from receiving a combination of viral antigens in promoting a border immune response against present and evolving contagious viruses. Lipid adjuvants demonstrated an enhanced response in the vaccine effect. This was seen in the significant immunogenicity effect when using the cationic lipid N3. Unlike L3, which showed a recognizable effect when administrated at a slightly higher concentration. Moreover, the findings of the study proved the efficiency of an intranasally mucosal immunization strategy, which can be less painful and more effective in enhancing the respiratory tract immunity against respiratory infectious diseases.Funding Agencies: TheKACST fund: (KINGABDULAZIZCITY FOR SCIENCEANDTECHNOLOGY "KACST") The MIIC stipend fund from Linköping University. Knut and Alice Wallenberg Foundation, Wallenberg Center for Molecular Medicine. The Structural Genomics Consortium is a registered charity (1097737) that receives funds from Bayer AG, Boehringer Ingelheim, BristolMyers Squibb, Genentech, Genome Canada through Ontario Genomics Institute [OGI-196]; EU/EFPIA/OICR/McGill/KTH/Diamond InnovativeMedicines Initiative 2 Joint Undertaking [EUbOPEN grant 875510]; Janssen, Merck KGaA (aka EMD in Canada and US); Pfizer; Takeda Stiftelsen for Strategisk Forskning (FFL15-0026).