Development of self assembling protein nanovaccines based on the spike protein of SARS-CoV-2 for induction of humoral response in a murine model

Abstract

In view of the current COVID-19 pandemic, the development of vaccination strategies against SARS-CoV-2 is a priority. Considering that risk groups are a priority, it is essential to develop vaccination strategies that have an adequate safety profile. In this context, subunits vaccines have been shown to be a promising alternative because they are safer, although they are often less immunogenic, which can be overcome with the use of adjuvants and nanoparticles (NPs). In this project, we propose the development of SAPN (Self Assembling Protein Nanoparticles) nanovaccines using receptor-binding domain (RBD) of the Spike protein as the main antigen, a structural protein that has been shown to be the main target for vaccine development. The RBD fragment will be modified by the insertion of peptides that favor the induction of neutralizing antibodies, as well as short sequences of peptides that confer the ability to self-structure in nanoparticles. Such nanovaccines will be produced in a eukaryotic system in order to preserve post-translational modifications, and their potential to induce humoral response will be evaluated in C57BL / 6 mice administered by the intramuscular route, using Enzyme-Linked Immunosorbent Assay (ELISA) to quantify the antigen-specific antibodies present in the serum from immunized animals. (AU)