Evaluation of the effect of murine antibodies against bacterial peptides associated with antimicrobial resistance

• Grant number: 24/18277-3
• Support Opportunities: Scholarships in Brazil - Program to Stimulate Scientific Vocations
• Start date: February 23, 2025
• End date: April 11, 2025
• Field of knowledge: Biological Sciences - Immunology - Cellular Immunology
• Principal Investigator: Priscilla Christina Olsen
• Grantee: Gabriele Santos Cepinho
• Host Institution: Faculdade de Farmácia. Universidade Federal do Rio de Janeiro (UFRJ). Ministério da Educação (Brasil)

Abstract

The spread of antimicrobial-resistant bacteria has become a serious public health problem worldwide. The existing antimicrobials are becoming obsolete and the development of new antimicrobials is at an extremely slow pace. It is necessary to invest in alternative approaches for the treatment of infections caused by these bacteria. One approach that can be explored is the use of antibodies against specific targets that are overexpressed in antimicrobial-resistant bacteria. In this project, we will target the outer membrane protein TolC, which is part of the efflux pump of Gram-negative bacteria and is overexpressed in the presence of selective pressure induced by antimicrobials. Recently, we found that the TolC protein of Escherichia coli is immunogenic, stimulating macrophages, T lymphocytes and B lymphocytes, leading to the production of antibodies in mice. Anti-TolC antibodies had a protective role against E. coli infection, acting through the increase of opsonophagocytosis. Since the extracellular portion of the TolC protein is the main target of antibodies, this project will investigate the effect of the peptides that constitute the extracellular portion of the TolC protein on the induction of protective antibodies against multidrug-resistant (MDR) E. coli. Thus, the student involved in the project will receive training to evaluate the expression of TolC in different strains of E. coli, through RT-PCR, and to manipulate mice immunized with the TolC peptide from E. coli (Ec01), in order to obtain serum antibodies and test their ability to bind with affinity to TolC, through Western blotting and ELISA assays. In addition to learning important methods for several subareas of Immunology and Microbiology, the student will participate in discussions of relevant and impactful scientific articles, in order to train her critical-analytical capacity. (AU)