An Immunoinformatic Approach to Identify the Conserved Epitopes of DBLβ2-PfEMP1 from Indonesian Plasmodium falciparum Isolate
Sheilla Rachmania (a,b*), Erma Sulistyaningsih (a,b,c), Anak Agung Istri Ratnadewi (a,c,d), and Rosita Dewi (a,b)
a) Graduate School of Biotechnology, University of Jember;
*sheilla.dr.fk[at]unej.ac.id
b) Faculty of Medicine, University of Jember;
c) Center for Development of Advance Science and Technology (CDAST), University of Jember,
d) Faculty of Mathematics and Natural Sciences, University of Jember
Abstract
Combatting malaria, as one of the world health burdens requires effective vaccine development, but high polymorphism in one protein vaccine candidate, Plasmodium falciparum erythrocyte membrane protein 1 (PfEMP1), is a major hurdle. One domain in its head structure, Duffy-binding like (DBL) domain, has a binding area to ICAM-1 receptor found in cerebral malaria patient, hence making this domain as a key to develop a malaria vaccine. Identify the epitopes within this protein is pivotal before formulating a peptide-based vaccine development strategy. This study aimed to identify the conserved epitopes by using an immunoinformatic approach. The protein was subjected to hydrophobicity attributes, Th-cell epitopes, and B-cell epitopes by using NN-align algorithm, Bepipred 2.0, and Kolaskar Tangaonkar methods combined with K-means clustering method to identify overlapping epitope. The result showed that the hydrophobicity value was 32.62 indicating that this protein is soluble and potentially fit into HLA alleles active site, but further NN-align algorithm showed no overlapping of Th-cell epitope positions for three Indonesian alleles. Three B-cell conserved epitopes in the position of 77-89, 236-254, and 360-377 amino acids were identified with one cluster overlapping with ICAM-1 determinant binding area. This information is valuable in constructing a subunit peptide-based malaria vaccine candidate.
Keywords: DBL2β, PfEMP1, epitope, immunoinformatic
Topic: Bioinformatics