The SARS-CoV-2 pandemic continues despite the presence of effective vaccines, and novel vaccine approaches may help to reduce viral spread and associated COVID-19 disease. Current vaccine administration modalities are based on systemic needle-administered immunisation which may be suboptimal for mucosal pathogens. Here we demonstrate in a mouse model that small-volume intranasal administration of purified spike (S) protein in the adjuvant polyethylenemine (PEI) elicits robust antibody responses with modest systemic neutralisation activity. Further, we test a heterologous intranasal immunisation regimen, priming with S and boosting with RBD-Fc. Our data identify small volume PEI adjuvantation as a novel platform with potential for protective mucosal vaccine development.
Journal of immunological methods
10/2022
Sir William Dunn School of Pathology, The University of Oxford, Oxford OX1 3RE, UK; The Department of Chemistry, The University of Oxford, OX1 3TA, UK. Electronic address: Lachlan.Deimel@path.ox.ac.uk.