The structure of a LAIR1-containing human antibody reveals a novel mechanism of antigen recognition
- University of Oxford, United Kingdom
Abstract
Antibodies are critical components of the human adaptive immune system, providing versatile scaffolds to display diverse antigen binding surfaces. Nevertheless, most antibodies have similar architectures, with the variable immunoglobulin domains of the heavy and light chain each providing three hypervariable loops, which are varied to generate diversity. The recent identification of a novel class of antibody in humans from malaria endemic regions of Africa was therefore surprising as one hypervariable loop contains the entire collagen-binding domain of human LAIR1. Here, we present the structure of the Fab fragment of such an antibody. We show that its antigen-binding site has adopted an architecture that positions LAIR1, while itself being occluded. This therefore represents an novel means of antigen recognition, in which the Fab fragment of an antibody acts as an adaptor, linking a human protein insert with antigen binding potential to the constant antibody regions which mediate immune cell recruitment.
Article and author information
Author details
Funding
Wellcome (101020/Z/13/Z)
- Fu-Lien Hsieh
- Matthew K Higgins
The funders had no role in study design, data collection and interpretation, or the decision to submit the work for publication.
Copyright
© 2017, Hsieh & Higgins
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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The structure of a LAIR1-containing human antibody reveals a novel mechanism of antigen recognition
eLife 6:e27311.
https://doi.org/10.7554/eLife.27311
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