Naturally acquired anti-RBP2b antibodies, red bllod cell invasion blockade, and protection from Plasmodium vivax Malaria

• Grant number: 24/02290-0
• Support Opportunities: Scholarships in Brazil - Post-Doctoral
• Start date: April 01, 2024
• Status: Discontinued
• Field of knowledge: Biological Sciences - Parasitology - Protozoology of Parasites
• Principal Investigator: Marcelo Urbano Ferreira
• Grantee: Natália Soares Ferreira
• Host Institution: Instituto de Ciências Biomédicas (ICB). Universidade de São Paulo (USP). São Paulo , SP, Brazil
• Associated research grant: 22/11963-3 - Individual variation in malaria risk: causes and consequences in Amazonian populations, AP.TEM
• Associated scholarship(s): 24/22944-5 - Primate malaria parasites as surrogate models to study invasion-blocking antibodies targeting the Plasmodium vivax reticulocyte binding protein 2b, BE.EP.PD

Abstract

Recently, the PvRBP2b protein was identified as a key invasion ligand for the malaria parasite Plasmodium vivax, as it binds to the transferrin-1 receptor (CD71) on the surface of immature red blood cells, known as reticulocytes, targeted by the parasite for invasion. Evidence has emerged that naturally acquired antibodies to PvRBP2b are associated with reduced malaria risk in both high- and low-transmission settings. Moreover, host-cell invasion by P. vivax can be partially inhibited ex vivo by murine monoclonal antibodies (mAbs) raised to recombinant PvRBP2b protein. Here we aim to test whether people exposed to low-level malaria transmission in the Brazilian Amazon develop anti-PvRBP2b antibodies that recognize the same epitopes than invasion-inhibitory murine mAbs, whether specific antibody responses are associated with reduced clinical malaria risk, and whether naturally acquired antibodies inhibit P. vivax invasion of reticulocytes ex vivo. (AU)