Polyspecific antigen binding by bovine immunoglobulin heavy- and light-chain variable domains
-
1
University of Guelph, Molecular and Cellular Biology, Canada
The complementarity regions (CDR) in the variable heavy and light chain domains of immunoglobulin determine the affinity and specificity of the antigen-binding site.
Generation of an exceptionally long CDR3H (up to 61 amino acids) in the bovine heavy chain variable region (VH) provides an additional mechanism to generate antibody diversity, not found in other species to date. These long CDR3H loops, present in polyspecific IgM, originate from VDJ recombination encoded by a specific VH gene, unusually long single DH-gene and insertion of 15-18 base long conserved short nucleotide sequences at VH-DH junction. In cattle, it is thought that antigen binding is mainly a function of the variable-region VH where light chain provides only structural support. To test this hypothesis, single chain variable fragment (scFv) and single domains (Fd) from polyspecific IgM were constructed. Both purified scFv and FdVH showed polyspecific binding to structurally dissimilar antigens in an ELISA. Whether scFv and FdVH bind to multiple epitopes on an antigen or if they recognize the same epitope can now be determined. The structural-functional complexities of these antibody fragments and the role of the heavy- and light-chains in antigen binding will be discussed.
Acknowledgements
Supported by NSERC Canada and Dairy Farmers of Ontario
Keywords:
polyspecific,
Immunoglobulin G,
bovine,
scFv,
single domain,
antibody fragments
Conference:
15th International Congress of Immunology (ICI), Milan, Italy, 22 Aug - 27 Aug, 2013.
Presentation Type:
Abstract
Topic:
Immune receptors and signaling
Citation:
Pasman
Y and
Kaushik
AK
(2013). Polyspecific antigen binding by bovine immunoglobulin heavy- and light-chain variable domains.
Front. Immunol.
Conference Abstract:
15th International Congress of Immunology (ICI).
doi: 10.3389/conf.fimmu.2013.02.01177
Copyright:
The abstracts in this collection have not been subject to any Frontiers peer review or checks, and are not endorsed by Frontiers.
They are made available through the Frontiers publishing platform as a service to conference organizers and presenters.
The copyright in the individual abstracts is owned by the author of each abstract or his/her employer unless otherwise stated.
Each abstract, as well as the collection of abstracts, are published under a Creative Commons CC-BY 4.0 (attribution) licence (https://creativecommons.org/licenses/by/4.0/) and may thus be reproduced, translated, adapted and be the subject of derivative works provided the authors and Frontiers are attributed.
For Frontiers’ terms and conditions please see https://www.frontiersin.org/legal/terms-and-conditions.
Received:
30 Jul 2013;
Published Online:
22 Aug 2013.
*
Correspondence:
Dr. Azad K Kaushik, University of Guelph, Molecular and Cellular Biology, Guelph, Ontario, N1G 2W1, Canada, akaushik@uoguelph.ca