Protective immunity induced by an inhaled SARS-CoV-2 subunit vaccine

• DOI: 10.1016/j.vaccine.2023.06.015
• Publication Date: 2023-06-06T16:12:45Z
• Authors: Elizabeth Elder; Chandrashekar Ban...; Catharina Johansson; Robert P.A. Wallin; Johan Sjödahl; Ola Winqvist; Ali Mirazimi
• Keywords: CD4-Positive T-Lymphocytes; COVID-19 Vaccines; COVID-19; Mice, Transgenic; Cross Reactions; CD8-Positive T-Lymphocytes; Antibodies, Viral; Article; 3. Good health; Mice; Vaccines, Subunit; Administration, Inhalation; Spike Glycoprotein, Coronavirus; Animals; Female; Powders

Targeting the site of infection is a promising strategy for improving vaccine effectivity. To date, licensed COVID-19 vaccines have been administered intramuscularly despite fact that SARS-CoV-2 respiratory virus. Here, we aim to induce local protective mucosal immune responses with an inhaled subunit candidate, ISR52, based on Spike S1 protein. When tested in lethal challenge hACE2 transgenic mouse model, intranasal and intratracheal administration ISR52 provided superior protection against severe infection, compared subcutaneous injection vaccine. Interestingly protein-based vaccine, elicited both CD4 CD8 T-cell Spike-specific were maintained at least 6 months wild-type mice. Induced IgG IgA cross-reacting several SARS- CoV-2 variants concern detected lung serum protected animals displayed neutralizing antibodies. Based our results, are developing as dry powder formulation inhalation, does not require cold-chain distribution or use needle administration, evaluation Phase I/II clinical trial.