PRODUCTION OF NEW VACCINE CANDIDATES EXPRESSED BY INVASIVE FORMS OF MDR Staphylococcus aureus

• Grant number: 25/05574-2
• Support Opportunities: Scholarships in Brazil - Scientific Initiation
• Start date: June 01, 2025
• End date: December 31, 2025
• Field of knowledge: Biological Sciences - Immunology - Applied Immunology
• Principal Investigator: Thiago Rojas Converso
• Grantee: Gabriela Claudia Mantini Cangussú
• Host Institution: Universidade São Francisco (USF). Campus Bragança Paulista. Bragança Paulista , SP, Brazil

Abstract

Staphylococcus aureus is a bacterial agent belonging to the human microbiota, with high pathogenicity to humans, classified as an opportunistic agent. Under specific circumstances, such as epithelial barrier breakdown, elevated body temperature, and deficient immunity, it can alter its biofilm (colonizing) phenotype to an invasive phenotype, causing infections in the body. Furthermore, it exhibits multidrug resistance to antimicrobials, making antibiotic therapeutic methods only partially effective due to the durability of the effectiveness of such therapies. Therefore, to combat this agent, preventive therapies have been studied. Thus, using recombinant DNA technology, the project proposes the production of new vaccine candidates expressed by the invasive forms of MDR Staphylococcus aureus for immunization through the production of recombinant proteins. This will be done using conventional PCR techniques to amplify genes of interest from the S. aureus NRS384 strain. After cloning, the genes will be inserted into the pGEM-T easy vector for cloning in the E. coli system and then into the Pet28a vector, which is specific for protein expression. For protein expression induction, IPTG will be used, and for purification, nickel affinity chromatography will be employed. The proteins will be confirmed by sequencing and Western Blot using a specific antibody against the histidine tag. In the end, the expressed proteins will be: ISDC_STAA8; Q2G1E9_STAA8; Q2FV70_STAA8; Q2G2E0_STAA8. So far, the project has successfully cloned two genes of interest. (AU)