The third complementary-determining regions of the heavy-chain (CDR3H) variable regions (VH) of some cattle antibodies are highly extended, consisting of 48 or more residues. These `ultralong' CDR3Hs form β-ribbon stalks that protrude from the surface of the antibody with a disulfide cross-linked knob region at their apex that dominates antigen interactions over the other CDR loops. The structure of the Fab fragment of a naturally paired bovine ultralong antibody (D08), identified by single B-cell sequencing, has been determined to 1.6 Å resolution. By swapping the D08 native light chain with that of an unrelated antigen-unknown ultralong antibody, it is shown that interactions between the CDR3s of the variable domains potentially affect the fine positioning of the ultralong CDR3H; however, comparison with other crystallographic structures shows that crystalline packing is also a major contributor. It is concluded that, on balance, the exact positioning of ultralong CDR3H loops is most likely to be due to the constraints of crystal packing.

Download full-text PDF

Source
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC11229553PMC
http://dx.doi.org/10.1107/S2053230X2400606XDOI Listing

Publication Analysis

Top Keywords

bovine ultralong
8
ultralong antibody
8
positioning ultralong
8
ultralong cdr3h
8
ultralong
5
impact exchanging
4
exchanging light
4
light heavy
4
heavy chains
4
chains structures
4

Similar Publications

Foot-and-mouth disease vaccination using inactivated virus is suboptimal, as the icosahedral viral capsids often disassemble into antigenically distinct pentameric units during long-term storage, or exposure to elevated temperature or lowered pH, and thus raise a response that is no longer protective. Furthermore, as foot-and-mouth disease virus (FMDV)'s seven serotypes are antigenically diverse, cross-protection from a single serotype vaccine is limited, and most existing mouse and bovine antibodies and camelid single-domain heavy chain-only antibodies are serotype-specific. For quality control purposes, there is a real need for pan-serotype antibodies that clearly distinguish between pentamer (12S) and protective intact FMDV capsid.

View Article and Find Full Text PDF

In cattle, colostral maternal immunoglobulins and lymphocytes transfer across the neonate's intestinal epithelium to provide protection against pathogens. This study aimed to compare repertoires of B cell populations in blood and colostrum in cows for the first time, with an emphasis on ultralong complementarity determining region 3 (CDR3, ≥40 amino acids). Blood mononuclear cells (BMCs, = 7) and colostral cells ( = 7) were isolated from Holstein-Friesian dairy cows.

View Article and Find Full Text PDF
Article Synopsis
  • - The study focuses on generating broadly neutralizing antibodies (bnAbs) against HIV's Envelope (Env) by immunizing cows, which show a reliable response compared to common animal models.
  • - Two groups of cows were given different regimens of V2-apex focusing immunogens, resulting in some cows producing serum neutralizing antibodies specifically targeting the V2-apex region of Env.
  • - The successful isolation of bnAbs from the cows, particularly those with ultralong CDRH3 regions, indicates that these antibodies are more effective in responding to highly glycosylated proteins like HIV Env.
View Article and Find Full Text PDF

Cattle produce Abs with an H chain ultralong CDR3 (40-70 aa). These Abs have been shown to have features such as broad neutralization of viruses and are investigated as human therapeutics. A common issue in sequencing the bovine BCR repertoire is the sequence length required to capture variable (V) and isotype gene information.

View Article and Find Full Text PDF

The impact of exchanging the light and heavy chains on the structures of bovine ultralong antibodies.

Acta Crystallogr F Struct Biol Commun

July 2024

The Division of Structural Biology, University of Oxford, Roosevelt Drive, Oxford OX3 7BN, United Kingdom.

The third complementary-determining regions of the heavy-chain (CDR3H) variable regions (VH) of some cattle antibodies are highly extended, consisting of 48 or more residues. These `ultralong' CDR3Hs form β-ribbon stalks that protrude from the surface of the antibody with a disulfide cross-linked knob region at their apex that dominates antigen interactions over the other CDR loops. The structure of the Fab fragment of a naturally paired bovine ultralong antibody (D08), identified by single B-cell sequencing, has been determined to 1.

View Article and Find Full Text PDF

Want AI Summaries of new PubMed Abstracts delivered to your In-box?

Enter search terms and have AI summaries delivered each week - change queries or unsubscribe any time!