Protein-based AB5-type exotoxin Pertussis toxin (PT) is produced by the bacterium Bordetella pertussis. PT can cause whooping cough.
In vitro: PT has the effect on innate immune response. The effects of PT on human monocyte-derived DC (MDDC), including maturation, are regulated by cAMP [1].
In vivo: Pertussis toxin did not affect the relaxation and contraction properties of isolated NIH or BALB/c mouse trachea, but significantly declined KCl or noradrenaline-induced maximal contraction and decreased sensitivity to noradrenaline in isolated male Wistar rat small mesenteric resistance arteries [2].
Clinical trial: Pertussis toxin was used as vaccine, acellular pertussis booster immunizations, to young and older persons in order to reduce the community transmission and to enhance the protection. Older persons with infections are mainly asymptomatic. Acellular pertussis boosters provide protection against symptomatic pertussis and give protection against mild and asymptomatic infections. The use of boosters may reduce transmission rate, especially in infant population [3].
References:
[1] Bagley KC, Abdelwahab SF, Tuskan RG, Fouts TR, Lewis GK. Pertussis toxin and the adenylate cyclase toxin from Bordetella pertussis activate human monocyte-derived dendritic cells and dominantly inhibit cytokine production through a cAMP-dependent pathway. J Leukoc Biol. 2002 Nov;72(5):962-9.
[2] van Meijeren CE, Vleeming W, van de Kuil T, Manni J, Kegler D, Hendriksen CF, de Wildt DJ. In vivo pertussis toxin treatment reduces contraction of rat resistance arteries but not that of mouse trachea. Eur J Pharmacol. 2004 Mar 19; 488 (1-3): 127-35.
[3] Ward JI, Cherry JD, Chang SJ, Partridge S, Keitel W, Edwards K, Lee M, Treanor J, Greenberg DP, Barenkamp S, Bernstein DI, Edelman R; APERT Study Group. Bordetella Pertussis infections in vaccinated and unvaccinated adolescents and adults, as assessed in a national prospective randomized Acellular Pertussis Vaccine Trial (APERT). Clin Infect Dis. 2006 Jul 15; 43 (2): 151-7. Epub 2006 Jun 5.