CD40 ligand as a potential adjuvant for a pan-variant intranasal vaccine against SARS-CoV-2

The COVID-19 pandemic began in December of 2019, following the identification of SARS-CoV-2, an coronavirus with likely zoonotic origins. Vaccination has been instrumental in global efforts to limit the extent of the pandemic, greatly reducing COVID-19-related mortality. Unfortunately, commercial SARS-CoV-2 vaccines have diminished efficacy against emerging variants, necessitating updated vaccine formulations and booster shots. Research into vaccination strategies capable of generating mucosal and variant-proof immunity is critical not only to limit the spread of future SARS-CoV-2 variants, but also for controlling future outbreaks of other viruses. We aim to evaluate the effectiveness of using CD40 ligand, a well-studied vaccine adjuvant, as part of intranasal vaccine formulation against SARS-CoV-2. We will compare the robustness of the vaccine to a traditional intramuscular counterpart, and determine the extent of protection afforded against immune escaping SARS-CoV-2 subvariants. This work will improve our understanding of the mechanisms underlying effective vaccination against SARS-CoV-2, which will be applicable for future emerging respiratory viruses as well.