Open AccessThis article is
- freely available
Development of an in Vitro Potency Assay for Anti-anthrax Lethal Toxin Neutralizing Antibodies
Division of Bacteriology, National Institute of Biological Standards and Control, HPA, Blanche Lane, Potters Bar, Hertfordshire EN6 3QG, UK
* Author to whom correspondence should be addressed.
Received: 9 December 2011; in revised form: 23 December 2011 / Accepted: 17 January 2012 / Published: 19 January 2012
Abstract: Lethal toxin (LT) of Bacillus anthracis reduces the production of a number of inflammatory mediators, including transcription factors, chemokines and cytokines in various human cell lines, leading to down-regulation of the host inflammatory response. Previously we showed that the reduction of interleukin-8 (IL-8) is a sensitive marker of LT-mediated intoxication in human neutrophil-like NB-4 cells and that IL-8 levels are restored to normality when therapeutic monoclonal antibodies (mAb) with toxin-neutralising (TN) activity are added. We used this information to develop cell-based assays that examine the effects of TN therapeutic mAbs designed to treat LT intoxication and here we extend these findings. We present an in vitro assay based on human endothelial cell line HUVEC jr2, which measures the TN activity of therapeutic anti-LT mAbs using IL-8 as a marker for intoxication. HUVEC jr2 cells have the advantage over NB-4 cells that they are adherent, do not require a differentiation step and can be used in a microtitre plate format and therefore can facilitate high throughput analysis. This human cell-based assay provides a valid alternative to the mouse macrophage assay as it is a more biologically relevant model of the effects of toxin-neutralising antibodies in human infection.
Keywords: anthrax; lethal toxin; toxin neutralisation
Citations to this Article
Cite This Article
MDPI and ACS Style
Whiting, G.; Baker, M.; Rijpkema, S. Development of an in Vitro Potency Assay for Anti-anthrax Lethal Toxin Neutralizing Antibodies. Toxins 2012, 4, 28-41.
Whiting G, Baker M, Rijpkema S. Development of an in Vitro Potency Assay for Anti-anthrax Lethal Toxin Neutralizing Antibodies. Toxins. 2012; 4(1):28-41.
Whiting, Gail; Baker, Michael; Rijpkema, Sjoerd. 2012. "Development of an in Vitro Potency Assay for Anti-anthrax Lethal Toxin Neutralizing Antibodies." Toxins 4, no. 1: 28-41.