United Kingdom (UK)
Recombinant monoclonal antibody to Ricin. Manufactured using AbAb’s Recombinant Platform with variable regions (i.e. specificity) from the phage display antibody F8(JOB10).
UniProt Accession Number of Target Protein: P02879
Alternative Name(s) of Target: rRNA N-glycosidase; Ricin A chain (EC:3.2.2.22); Ricin B chain
Immunogen: The original antibody was generated by immunizing alpacas, followed by library construction and panning on RTA.
Specificity: The antibody is specific for RTA. The antibody's principal contacts with RTA were centered on β–strand h, with lesser interactions occurring with α–helix B and α–helix D. Ricin is a member of the type II ribosome-inactivating protein (RIP) family of plant toxins. It is a 65 kDa glycoprotein consisting of two subunits, RTA and RTB, joined by a single disulfide bond.
Application Notes: The crystal structure of the VHH antibody in complex with the ricin toxin's enzymatic subunit (RTA) was solved. The specificity of the original format of the antibody was confirmed by ELISA analysis, and the antibody's EC50 for ricin holotoxin was 0.5-0.8 nM. The binding affinity of the VHH fragments to ricin was measured by surface plasmon resonance (Kd= 0.2 nM). In the Vero cell cytotoxicity assay, the VHH had an IC50 of ∼300 nM, thereby classifying it as a weak neutralizing antibody (Rudolph et al., 2016; PMID: 27159829).
Antibody first published in:
Rudolph et al. Structural analysis of nested neutralizing and non-neutralizing B cell epitopes on ricin toxin's enzymatic subunit. Proteins. 2016 Aug;84(8):1162-72. PMID:27159829
Note on publication:
The paper describes the generation and characterization of the antibody.