SCREENING AND EVALUATION OF ANTIGENIC B-CELL EPITOPES FOR THE SERODIAGNOSIS OF LYMPHATIC FILARIASIS

Abstract

Lymphatic Filariasis (LF) is a parasitic disease transmitted to humans via mosquitoes and a major public health problem in tropical countries which requires transmission assessment tools for elimination. The objective of this study is to predict B-cell epitopes from 3D structures of antigens using In silico tools and also evaluate their diagnostic potential using clinical sera samples. The epitopes were predicted on the basis of Amino Acid Pair/ Kernel method by using ABCpred, BCpred and Bepipred servers. The amino acid sequences of Wuchereria bancrofti Abundant Larval Transcript -2 (Wb- ALT-2) and Cuticlin (Wb-CUT) were submitted to the servers and the epitopes obtained. Further, protein homology models of Wb-ALT-2 and Wb-CUT were developed using the SWISS-MODEL database and the epitopes were analysed for its position in 3D models. Finally, seven epitopes from Wb- ALT-2 and Wb-CUT were selected and their diagnostic potential in clinical samples by indirect Enzyme Linked Immuno Sorbent Assay (ELISA) was evaluated. Peptides P2 and P3 have potential in detecting the exposure to LF infection. Similarly, peptide P6 of Wb-CUT showed good specificity- sensitivity in IgG4 format and also detected a large number of EN samples as positives. The results indicate that peptide P1 and P2 of Wb-ALT-2 antigen and P6 of Wb-CUT have potential application in the diagnosis of LF.