Crystal structures of the human IgD Fab reveal insights into CH1 domain diversity

DOI: 10.1016/j.molimm.2023.05.006

Authors: Anna M. Davies (King's College London) , Rebecca L. Beavil (King's College London) , Momchil Barbolov (King's College London) , Balraj S. Sandhar (King's College London) , Hannah J. Gould (King's College London) , Andrew J. Beavil (King's College London) , Brian Sutton (King's College London) , James M. Mcdonnell (King's College London)
Co-authored by industrial partner: No

Type: Journal Paper
Journal: Molecular Immunology , VOL 159 , PAGES 28 - 37

State: Published (Approved)
Published: July 2023
Diamond Proposal Number(s): 25301

Abstract: Antibodies of the IgD isotype remain the least well characterized of the mammalian immunoglobulin isotypes. Here we report three-dimensional structures for the Fab region of IgD, based on four different crystal structures, at resolutions of 1.45–2.75 Å. These IgD Fab crystals provide the first high-resolution views of the unique Cδ1 domain. Structural comparisons identify regions of conformational diversity within the Cδ1 domain, as well as among the homologous domains of Cα1, Cγ1 and Cμ1. The IgD Fab structure also possesses a unique conformation of the upper hinge region, which may contribute to the overall disposition of the very long linker sequence between the Fab and Fc regions found in human IgD. Structural similarities observed between IgD and IgG, and differences with IgA and IgM, are consistent with predicted evolutionary relationships for the mammalian antibody isotypes.

Journal Keywords: IgD; CH1 domain; Fab; Antibody; Immunoglobulin; X-ray crystallography

Subject Areas: Biology and Bio-materials


Instruments: I04-1-Macromolecular Crystallography (fixed wavelength)

Added On: 05/06/2023 09:35

Discipline Tags:

Structural biology Life Sciences & Biotech

Technical Tags:

Diffraction Macromolecular Crystallography (MX)