OBTAINING AND CHARACTERIZING RECOMBINANT EPITOPES AND ANTIBODIES EXCLUSIVE TO DENGUE: PROSPECTING IMMUNOBIOLOGICAL TOOL

• Grant number: 24/01846-5
• Support Opportunities: Scholarships in Brazil - Master
• Start date: July 01, 2024
• End date: March 31, 2026
• Field of knowledge: Health Sciences - Collective Health - Public Health
• Principal Investigator: Daniela Luz Hessel da Cunha
• Grantee: Joyce Araújo de Oliveira
• Host Institution: Instituto Butantan. Secretaria da Saúde (São Paulo - Estado). São Paulo , SP, Brazil

Abstract

Dengue is a neglected viral disease that infects and kills thousands of people each year. In areas where arboviruses co-circulate, the differential diagnosis of the disease is challenging due to the possibility of serum antibody cross-reactivity to other flaviviruses. This scenario is exacerbated by the lack of safe and effective vaccines widely available to the general population. It is therefore essential to develop new immunobiological tools that target this pathogen and all its variants. Antibodies are molecules widely used as diagnostic and therapeutic tools for various diseases due to their high specificity and affinity. Using recombinant DNA technology and methods such as phage display, it is also possible to obtain from VhH (nanobodies) obtained from the immunization of camelids, whose immunoglobulins are differentiated and generate unique biomolecules of antigen recognition to fragments of recombinant antibodies (rAbs), such as scFv, Fab chains, with in vitro immunological repertoires, without the need for direct immunization of living hosts. In a previous study, we identified and characterized in silico two immunogenic epitopes of the dengue virus (DENV) NS1 protein, from a region conserved in the four circulating serotypes of the virus and without homology with other mosquito-borne flaviviruses. Therefore, this study aims to optimize the recombinant production of these peptides to be used as antigens in the development of different formats of recombinant antibodies (VhH, Fab and scFv) differential to DENV, via phage display. These antibodies will be purified and characterized for their specificity and sensitivity to both the target peptide and the native NS-1 protein. Once these tools are obtained, it is expected to explore new possibilities for the development of more accurate detection tests and efficient therapeutic strategies that can contribute to the surveillance, correct treatment and prevention of dengue. This work is backing by the Centro para Vigilância Viral e Avaliação Sorológica (CeVIVAS), one of the research units of the Centros de Ciência para o Desenvolvimento (CCDs-SP) supported by FAPESP, located at the Instituto Butantan.