Activation of the SHP-1 Phosphatase in Macrophages through cAMP-Dependent Blocks Induction of Bactericidal Nitric Oxide Adenylate Cyclase Toxin Bordetella pertussis
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منابع مشابه
Invasion of Dendritic Cells, Macrophages and Neutrophils by the Bordetella Adenylate Cyclase Toxin: A Subversive Move to Fool Host Immunity
Adenylate cyclase toxin (CyaA) is released in the course of B. pertussis infection in the host's respiratory tract in order to suppress its early innate and subsequent adaptive immune defense. CD11b-expressing dendritic cells (DC), macrophages and neutrophils are professional phagocytes and key players of the innate immune system that provide a first line of defense against invading pathogens. ...
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Bordetella pertussis, the bacterium that causes whooping cough, secretes an adenylate cyclase toxin (ACT) that must be post-translationally palmitoylated in the bacterium cytosol to be active. The toxin targets phagocytes expressing the CD11b/CD18 integrin receptor. It delivers a catalytic adenylate cyclase domain into the target cell cytosol producing a rapid increase of intracellular cAMP con...
متن کاملPertussis 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.
Pertussis toxin (PT) and adenylate cyclase toxin (AT) are AB enterotoxins produced by Bordetella pertussis. PT is a powerful mucosal adjuvant whose cellular target and mechanism of action are unknown; however, emerging evidence suggests that dendritic cells (DC) may be a principal adjuvant target of PT. Here, we investigate the mechanism underlying the effects of these toxins on human monocyte-...
متن کاملCyclic AMP-mediated suppression of neutrophil extracellular trap formation and apoptosis by the Bordetella pertussis adenylate cyclase toxin.
The adenylate cyclase toxin (ACT) of Bordetella pertussis intoxicates target cells by generating supraphysiologic levels of intracellular cyclic AMP (cAMP). Since ACT kills macrophages rapidly and potently, we asked whether ACT would also kill neutrophils. In fact, ACT prolongs the neutrophil life span by inhibiting constitutive apoptosis and preventing apoptosis induced by exposure to live B. ...
متن کاملBordetella parapertussis Circumvents Neutrophil Extracellular Bactericidal Mechanisms
B. parapertussis is a whooping cough etiological agent with the ability to evade the immune response induced by pertussis vaccines. We previously demonstrated that in the absence of opsonic antibodies B. parapertussis hampers phagocytosis by neutrophils and macrophages and, when phagocytosed, blocks intracellular killing by interfering with phagolysosomal fusion. But neutrophils can kill and/or...
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