Loading…

In vitro potency determination of botulinum neurotoxin serotype A based on its receptor-binding and proteolytic characteristics

Botulinum neurotoxins (BoNTs) inhibit the release of the neurotransmitter acetylcholine from motor neurons, resulting in highly effective muscle relaxation. In clinical and aesthetic medicine, serotype BoNT/A, which is most potent for humans, is widely used to treat a continuously increasing spectru...

Full description

Saved in:
Bibliographic Details
Published in:Toxicology in vitro 2018-12, Vol.53, p.80-88
Main Authors: Behrensdorf-Nicol, Heike A., Wild, Emina, Bonifas, Ursula, Klimek, Jolanta, Hanschmann, Kay-Martin, Krämer, Beate, Kegel, Birgit
Format: Article
Language:English
Subjects:
Citations: Items that this one cites
Items that cite this one
Online Access:Get full text
Tags: Add Tag
No Tags, Be the first to tag this record!
Description
Summary:Botulinum neurotoxins (BoNTs) inhibit the release of the neurotransmitter acetylcholine from motor neurons, resulting in highly effective muscle relaxation. In clinical and aesthetic medicine, serotype BoNT/A, which is most potent for humans, is widely used to treat a continuously increasing spectrum of disorders associated with muscle overactivity. Because of the high toxicity associated with BoNTs, it is mandatory to precisely determine the potency of every batch produced for pharmaceutical purposes. Here we report a new quantitative functional in vitro assay for BoNT/A. In this binding and cleavage (BINACLE) assay, the toxin is first bound to specific receptor molecules. Then a chemical reduction is performed, thereby releasing the light chain of BoNT/A and activating its proteolytic domain. The activated light chain is finally exposed to its substrate protein SNAP-25, and the fragment resulting from the proteolytic cleavage of this protein is quantified in an antibody-mediated reaction. The BoNT/A BINACLE assay offers high specificity and sensitivity with a detection limit below 0.5 mouse lethal dose (LD50)/ml. In conclusion, this new in vitro assay for determining BoNT/A toxicity represents an alternative to the LD50 test in mice, which is the “gold standard” method for the potency testing of BoNT/A products. •The BoNT/A BINACLE assay can assess the specific activity and potency of BoNT/A.•A SV2C-derived peptide and ganglioside GT1b are used to specifically bind BoNT/A.•After binding, active BoNT/A is quantified based on its SNAP-25-cleaving activity.•
ISSN:0887-2333
1879-3177
DOI:10.1016/j.tiv.2018.07.008