PHYSIOLOGICALLY RELEVANT EXPRESSION & FUNCTIONAL CHARACTERIZATION OF PLASMODIUM(P.) FALCIPARUM DERIVED VARIANT STEVOR ANTIGENS USING BIOPHYSICAL ASSAYS

Abstract

STEVOR, THE 3RD LARGEST VSA GROUP EXPORTED BY THE P. FALCIPARUM PARASITE, IS INVOLVED IN REMODELLING OF HOST RBC. HERE, BASED ON EXPERIMENTS WITH A SET OF STEVOR SELECTED AND ENGINEERED STRAINS, WE PROVIDED AN EXTENSIVE CHARACTERIZATION STUDY OF STEVOR PROTEINS. USING MOLECULAR FORCE SPECTROSCOPY AND IMMUNO-ELECTRON MICROSCOPY TECHNIQUES, WE DEMONSTRATED THAT DURING LATE ASEXUAL STAGES, STEVOR PROTEINS GET EXPORTED TO THE INFECTED ERYTHROCYTE SURFACE WHERE THEY OLIGOMERIZE IN DIFFERENT SIZES AND THE SURFACE EXPRESSION OF PROTEINS CONSTANTLY INCREASES WITH PARASITE MATURATION. NEXT, USING DUAL-PIPETTE FORCE ASSAY AND MICROFLUIDICS BASED FLOW ASSAY, WE ESTABLISHED THAT STEVOR PROTEINS CAN MEDIATE THE FORMATION OF STABLE ROSETTES UNDER STATIC AS WELL AS DYNAMIC CONDITIONS. OUR RESULTS ALSO SUPPORT THE 1 TRANSMEMBRANE MODEL FOR STEVOR. OVERALL, OUR WORK PROVIDED NEW STRUCTURAL AND FUNCTIONAL INSIGHTS ABOUT THE STEVOR FAMILY, CONTRIBUTING IN BETTER UNDERSTANDING OF MALARIA PATHOLOGY AND D