Epitope-based Strategy for the Differential and Specific Diagnosis of Dengue

• Grant number: 25/19577-3
• Support Opportunities: Scholarships abroad - Research Internship - Master's degree
• Start date: October 01, 2025
• End date: December 31, 2025
• Field of knowledge: Health Sciences - Collective Health - Public Health
• Principal Investigator: Daniela Luz Hessel da Cunha
• Grantee: Joyce Araújo de Oliveira
• Supervisor: Ario de Marco
• Host Institution: Instituto Butantan. São Paulo , SP, Brazil
• Institution abroad: University Of Nova Gorica, Slovenia
• Associated to the scholarship: 24/01846-5 - OBTAINING AND CHARACTERIZING RECOMBINANT EPITOPES AND ANTIBODIES EXCLUSIVE TO DENGUE: PROSPECTING IMMUNOBIOLOGICAL TOOL, BP.MS

Abstract

Dengue is a viral disease that can progress to severe illness and even death. In regions where multiple arboviruses co-circulate, diagnosis is hindered by overlapping clinical manifestations and the cross-reactivity of antibodies among flaviviruses in serological assays, often resulting in inaccurate or inconclusive outcomes. The absence of reliable biomarkers for circulating serotypes further complicates case confirmation. Antibodies, due to their high affinity and specificity, represent essential biotechnological tools for the detection of viral antigens. VHHs are a format of heavy chain antibodies (HCAbs) that are smaller, with unique structures that allow binding to epitopes that are inaccessible to conventional antibodies. These structural advantages make nanobodies promising candidates for diagnostic applications. Previous, in silico analyses identified two conserved NS1 protein epitopes shared across all four DENV serotypes, with minimal sequence identity to other arboviruses. A synthetic peptide was designed to incorporate both epitopes in a single construct, with the possibility of separation by endopeptidase cleavage. Structural modeling predicted immunogenicity, solubility, and accessibility for antibody binding, supporting their potential as specific diagnostic targets. The aim of this proposal is to perform an innovative in silico panning process, using synthetic VHH library diversity and molecular docking in order to predict optimal candidates targeting these pan-DENV epitopes, followed by their production in a microbial expression system and its empiric validation as immunobiological tools to be used in DENV differential diagnosis.