Title:Beyond B-Cell Epitopes: Curating Positive Data on Antipeptide Paratope Binding to Support Peptide-Based Vaccine Design
Volume: 28
Issue: 8
Author(s): Salvador Eugenio C. Caoili*
Affiliation:
- Biomedical Innovations Research for Translational Health Science (BIRTHS) Laboratory, Department of Biochemistry and Molecular Biology, College of Medicine, University of the Philippines Manila, Manila,Philippines
Keywords:
Epitopes, paratopes, antigens, antibodies, peptides, proteins, vaccines, conformational disorder.
Abstract:
Background: B-cell epitope prediction is a computational approach originally developed
to support the design of peptide-based vaccines for inducing protective antibody-mediated immunity,
as exemplified by neutralization of biological activity (e.g., pathogen infectivity). Said approach
is benchmarked against experimentally obtained data on paratope-epitope binding; but such
data are curated primarily on the basis of immune-complex structure, obscuring the role of antigen
conformational disorder in the underlying immune recognition process.
Objective: This work aimed to critically analyze the curation of epitope-paratope binding data that
are relevant to B-cell epitope prediction for peptide-based vaccine design.
Methods: Database records on neutralizing monoclonal antipeptide antibody immune-complex
structure were retrieved from the Immune Epitope Database (IEDB) and analyzed in relation to
other data from both IEDB and external sources including the Protein Data Bank (PDB) and published
literature, with special attention to data on conformational disorder among paratope-bound
and unbound peptidic antigens.
Results: Data analysis revealed key examples of antipeptide antibodies that recognize conformationally
disordered B-cell epitopes and thereby neutralize the biological activity of cognate targets
(e.g., proteins and pathogens), with inconsistency noted in the mapping of some epitopes due to reliance
on immune-complex structural details, which vary even among experiments utilizing the
same paratope-epitope combination (e.g., with the epitope forming part of a peptide or a protein).
Conclusion: The results suggest an alternative approach to curating paratope-epitope binding data
based on neutralization of biological activity by polyclonal antipeptide antibodies, with reference
to immunogenic peptide sequences and their conformational disorder in unbound antigen structures.