Chromatography purification of rabies Virus-Like Particles

• Grant number: 21/14574-5
• Support Opportunities: Scholarships in Brazil - Master
• Start date: September 01, 2022
• End date: March 31, 2024
• Field of knowledge: Health Sciences - Pharmacy
• Principal Investigator: Eutimio Gustavo Fernández Núñez
• Grantee: Jean Lucas Tanaka
• Host Institution: Escola de Artes, Ciências e Humanidades (EACH). Universidade de São Paulo (USP). São Paulo , SP, Brazil

Abstract

The main focus of vaccines is to induce adaptive immune response in the host. To achieve this effect, the vaccine preparation mimics the real infection stimulating the immune system and if a real infection occurs, the organisms might respond at much faster rate, preventing disease development. Vaccines may be effective in several diseases mainly viral diseases, since viruses may have a great capacity to spread, to cause post infection sequelae and high lethality such as SARS-CoV-2, Zika, e rabies virus. In this day and age, rabies is endemic in more than 150 countries and causes about 59.000 deaths every year worldwide, mainly in the poorest and most vulnerable communities. New platforms for viral vaccines production are constantly developed that can address limitations of classical strategies based on attenuated or inactivated viruses, or protein subunits, such as demand and safety. Among the most recent technologies are Virus Like Particles (VLP), nanoparticles constructed of proteins morphologically similar to protein found in viruses, causing significant immune response in the host. The use of baculovirus/insect cell (B/IC) system has a prominent place in the production of VLPs and can be produced from two methodologies, coinfection and coexpression. This platform has as a major bottleneck, the purification of the VLPs produced in a lytic viral infection process. Thus, the present proposal aims to develop and optimize a protocol for purification of rabies VLP after the cell clarification step, using two chromatographic techniques, one based on ion exchange and the other bimodal (hydrophobic interactions/size exclusion) in order to achieve high purity VLP that allow immunological evaluation through in vitro studies and in animal models. The horseradish VLPs will be obtained from an already optimized bioreactor procedure based on the infection of Sf9 insect cells by recombinant baculoviruses carrying the Matrix protein and the G-glycoprotein of the horseradish virus.