Vaccine Strategy

The pandemic resulting from the introduction of SARS-CoV-2 into the human population worldwide defines an urgent need for new vaccines that can induce broadly protective responses with increased potency and durability. Our solution for this challenge is to target both B cell and multiple T cell responses, via presentation of a greater variety of antigenic epitopes, together with an immune potentiator in a single, safe, virus-sized particle, the exosome. Upon subcutaneous delivery, exosomes traffic in lymphatics to lymph nodes where, by virtue of their size, they are readily taken up by key antigen presenting dendritic cells (DCs). The rapid access of antigen to DCs activates effective B and T cell responses, and cross priming needed for induction of potent CD8 T cells. The SARS-CoV2 vaccine is being used as a prototype to develop other exosome-based vaccines based on the same principles, including a pan-coronavirus and novel vaccines to emerging epidemics.