Human Bordetella pertussis IgG ELISA Kit

Pertussis is an acute respiratory disease that severely affects young children, is highly contagious, and can be spread by aerosols. Bordetella pertussis, the pathogen that causes pertussis, re-emerges in countries with high vaccine coverage, despite very high global vaccination coverage. This may be due to the shift in vaccines used for pertussis from whole-cell pertussis (wP) vaccine preparations, which contain many of the characteristic bacterial proteins, to the less reactive 1-5 component acellular pertussis (aP) vaccine, which prevents the disease but is less protective and does not prevent colonization and transmission of the pathogen. In addition, advances in diagnostic techniques, and antigenic drift of prevalent strains due to vaccines may have contributed to the increased incidence of pertussis.

The genus Bordetella contains many species, most of which have been isolated from severely immunocompromised individuals, and only a few, such as Bordetella petrii, have so far been isolated only from the natural environment. Of the 16 known species of Bordetella, three are bona fide pathogens of humans and other mammals, including B. bronchiseptica, B. pertussis and Bordetella parapertussis. These three strains share many virulence factors and virulence factors, but differ in their host range and infection specificity. Of these, B. bronchiseptica colonizes a wide range of mammalian species, primarily causing chronic respiratory infections and surviving in environments other than mammalian hosts. B. pertussis and Bordetella parapertussis can only infect humans, causing acute respiratory infections, and do not survive in the natural environment. Infection with B. pertussis in newborns and young children is life-threatening, and the course of the disease can be divided into three stages, catarrhal, paroxysmal, and convalescent. It begins with cold-like symptoms and progresses to a paroxysmal cough, which is compulsive, with a characteristic "whooping" sound due to labored breathing, and may lead to apnea and cyanosis.

The virulence-regulated genome of B. pertussis contains more than 200 genes that are coordinated by the two-component system BvgAS. BvgS is a sensor kinase that is active by default at a temperature of 37°C. In the Bvg⁺ phase, BvgS does not require an activating ligand to induce its own phosphorylation, and then transfers the phosphate group to the transcriptional activator BvgA. Phosphorylated BvgA triggers the expression of virus-activating genes (vags), and BvgS increases the expression of virus-repressor genes (vrgs) by turning off the phosphorylation cascade in response to chemical stimuli such as sulfate or nicotinic acid ions. Vags primarily encode toxins and adhesins and their secretion mechanisms. Many virulence factors of B. pertussis have immunomodulatory properties and play an important role in host-pathogen interactions. Current aPVs mainly cover several virulence factors such as FHA, PTX, Prn and fimbriae.

Figure 1. Regulatory network of the virulence factors in B. pertussis
(Source: Belcher T, et al. 2021)

Human B. pertussis IgG ELISA Kit