Optimization of SARS-CoV-2 antigen production in Expi293 cell culture aiming OMV-based vaccine generation

• Grant number: 21/14376-9
• Support Opportunities: Scholarships in Brazil - Master
• Start date: September 01, 2022
• End date: August 31, 2023
• Field of knowledge: Biological Sciences - Biochemistry - Molecular Biology
• Principal Investigator: Luciana Cezar de Cerqueira Leite
• Grantee: Arthur Daniel Januzzi
• Host Institution: Instituto Butantan. Secretaria da Saúde (São Paulo - Estado). São Paulo , SP, Brazil
• Associated research grant: 17/24832-6 - Development of vaccines based on recombinant BCG: Tuberculosis, Pertussis, Pneumococcus and Schistosoma, AP.TEM

Abstract

The vaccines currently in use against the SARS-CoV-2 coronavirus were developed based on both traditional processes and more modern technologies such as viral vectors and RNA-based vaccines. These new strategies were very effective and safe in clinical trials and have shown great efficiency in the control of COVID-19. These approaches take into account the presentation of important antigens for the generation of a protective immune response through potent delivery systems. Previous results from our laboratory have demonstrated the ability of Outer Membrane Vesicle (OMV) vesicles as an antigen presenting system. The system based on the coupling of antigens in fusion to rizavidin and on the biotinylation of OMV, when applied to Schistosoma mansoni, allowed the induction of IgG antibodies at levels much higher than those induced by the uncoupled antigen. One of the biggest challenges encountered in that project was to obtain adequate amounts of recombinant antigens in fusion with rizavidin (Ag-Rzv). This Escherichia coli-based expression system, when applied to the production of SARS-CoV-2 antigens in fusion with rizavidin, proved to be fruitless. Following the development of our OMV-based vaccine platform, this project aims to optimize the production of Ag-Rzv recombinant antigens using the efficient Expi293F cell culture system and the coupling of these antigens in OMV. We expect that the OMV system presenting SARS-CoV-2 antigens will induce a humoral immune response as potent as that previously obtained with Schistosoma antigens. (AU)