Modified binding assay for improved sensitivity and specificity in the detection of residual pertussis toxin in vaccine preparations

Enhanced Immune Response Against Pertussis Toxoid by IgA-Loaded Chitosan–Dextran Sulfate Nanoparticles

“…The CHO cell agglutination assay is usually used for testing for the safety of acellular pertussis‐containing vaccines 23,29,30. Agglutination of CHO cells is a reflection of PTX activity, as it requires both binding and enzymatic functions of the toxin 27,31. Clustering of CHO cells was clearly observed (Fig.…”

“…Although whole‐cell pertussis vaccines have been used for many decades and are still commonly used in the developing world, the more recent development and introduction of acellular pertussis vaccines has both increased the compliance with vaccination programs and reduced the severity of adverse reactions to the vaccine 25,26. PTX is toxic if administered at a dose required for effective vaccination27; therefore, its detoxified form (PTXd) is included in acellular pertussis vaccine formulations. Most commercial acellular pertussis vaccines contain chemically detoxified PTX, with a smaller number using genetically detoxified PTX.…”

Identification of biomarkers to detect residual pertussis toxin using microarray analysis of dendritic cells

“…This approach might be of interest for pertussis vaccine safety testing since not all effector mechanisms of PTx are completely understood, nor are all of its clinical effects [17,18]. Current in vitro alternatives under development to replace the HIST focus mainly on the binding and entry of PTx and consequent ADP-ribosylation of G i proteins [14][15][16]. Although the enzymatic activity is a principal activity of PTx involved in many of its biological effects, over the past years several studies have described PTx effects independent of this enzymatic activity [21,22,27,28].…”

“…Several in vitro alternatives are currently under development, i.e. a cAMP assay in rat A10 cells [14], a fetuin binding assay [15,16] and an enzymatic HPLC method [15]. These assays reflect known activities of PTx, i.e.…”

Immunomodulation as a Novel Strategy for Prevention and Treatment of Bordetella spp. Infections

“…Pertussis toxin (PTX) in an inactivated form (PTd) functions as a major protective antigen, stimulating production of toxinneutralizing antibodies which can protect against damage caused by the toxin, but do not target the bacteria itself (301,302); however, it also demonstrates possible partial reversion back to its toxic active form (303,304), which may be responsible for the reactogenicity seen in a small percentage of vaccine recipients. It is also a secretory protein, which is only loosely associated with the cell and is therefore not an ideal target for bactericidal antibodies.…”