Computationally-driven identification of antibody epitopes
Abstract
Understanding where antibodies recognize antigens can help define mechanisms of action and provide insights into progression of immune responses. We investigate the extent to which information about binding specificity implicitly encoded in amino acid sequence can be leveraged to identify antibody epitopes. In computationally-driven epitope localization, possible antibody-antigen binding modes are modeled, and targeted panels of antigen variants are designed to experimentally test these hypotheses. Prospective application of this approach to two antibodies enabled epitope localization using five or fewer variants per antibody, or alternatively, a six-variant panel for both simultaneously. Retrospective analysis of a variety of antibodies and antigens demonstrated an almost 90% success rate with an average of three antigen variants, further supporting the observation that the combination of computational modeling and protein design can reveal key determinants of antibody-antigen binding and enable efficient studies of collections of antibodies identified from polyclonal samples or engineered libraries.
Article and author information
Author details
Funding
National Institutes of Health (R01 GM098977)
- Chris Bailey-Kellogg
National Research Foundation of Korea (2016H1D3A1938246)
- Yoonjoo Choi
National Science Foundation (CNS-1205521)
- Chris Bailey-Kellogg
National Institutes of Health (5F30 AI122970-02)
- Casey K Hua
National Institutes of Health (1R01AI102691)
- Margaret E Ackerman
Center of Biomedical Research Excellence (8P30GM103415)
- Charles L Sentman
- Margaret E Ackerman
Allan U. Munck Education and Research Fund at Dartmouth
- Charles L Sentman
- Margaret E Ackerman
The funders had no role in study design, data collection and interpretation, or the decision to submit the work for publication.
Reviewing Editor
- Max Vasquez, Adimab Inc., United States
Version history
- Received: May 26, 2017
- Accepted: December 2, 2017
- Accepted Manuscript published: December 4, 2017 (version 1)
- Version of Record published: December 21, 2017 (version 2)
Copyright
© 2017, Hua et al.
This article is distributed under the terms of the Creative Commons Attribution License permitting unrestricted use and redistribution provided that the original author and source are credited.
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