Anti-PA anthrax [W2]

Absolute Antibody

Anti-PA anthrax [W2]

7

This antibody recognizes protective antigen (PA) of anthrax toxin. W2 antibody targets a conformational epitope formed by C-terminal amino acids 614-735 of PA (Chen et al., 2006; pmid: 16453257). W2 is thought to recognize the same neutralizing epitope as

The original scFv version of this antibody was confirmed to strongly bind anthrax protective antigen (PA) by ELISA (Chen et al., 2006; pmid: 16453257). This format was further shown to inhibit the effects of anthrax toxin. To perform subsequent tests, W2 clone was turned into an IgG1 version. This format of W2 exhibited very potent neutralizing activity against PA in the the RAW264.7 cell-based in vitro assay (its neutralizing capabilities were 5-fold higher than of the popular murine anti-PA clone 14B7 (Chen et al., 2006; pmid: 16453257). Furthermore, W2 had one of the highest affinities against anthrax PA ever recorder (Kd = 5e-11 mol/L) (Chen et al., 2006; pmid: 16453257). What is more, Western blot analysis showed that W2 neutralizes the toxin by blocking binding of PA to the cellular receptor (Chen et al., 2006; pmid: 16453257). Finally, IgG1 version of this antibody fully protected rats from anthrax toxin challenge even when the antibody had been injected 1 week before the toxin challenge, demonstrating its slow dissociation rate crucial in potential clinical use (Chen et al., 2006; pmid: 16453257). This confirms that W2 antibody can be further researched as a potential therapeutic agent as PA entry inhibitor for use in the emergency prophylaxis against and treatment of anthrax as well as a post-exposure therapy (Manish et al., 2020; pmid: 32729741).This clone can be also potentially used in the development of protective therapies against bioterrorism and biological warfare where anthrax toxins have been used (Bouzianas, 2009; pmid: 19781945).

Western Blot, ELISA, Neutralisation/Blocking

neutralizing; WB; ELISA

Research Use Only

Monoclonal

W2

pxo1_110

pXO1-110

pxo1_110; pXO1-110

Human

IgG1

Protective antigen

This full-length, chimeric human antibody was made using the variable domain sequences of the original scFv format, for improved compatibility with existing reagents, assays and techniques.

Bacteria

Bacillus anthracis

The original scFv version of this antibody was isolated from a phage display library generated from immunized chimpanzees.

-20°C,2°C to 8°C

12352203