Uptake and intracellular survival of Bordetella pertussis in human macrophages.
نویسندگان
چکیده
Recent reports have demonstrated that Bordetella pertussis has invasive behavior in vivo and in vitro. In this study, we investigated the ability of a virulent strain, avirulent mutants, and mutants deficient in specific virulence factors to enter and survive intracellularly in human macrophages in vitro. Uptake of virulent B. pertussis was dose dependent and occurred in the absence of serum or specific antibody, with entry occurring via a microfilament-dependent phagocytic process. The virulent wild-type parental strain was internalized and persisted intracellularly over the 3 days of experiments, as determined by transmission electron microscopy and by recovery of viable plate counts. This is the first report of long-term survival of B. pertussis in human macrophages. Avirulent mutants entered macrophages, but at only an average of 1.5% of virulent parental levels, and did not survive intracellularly. Mutants which did not express adenylate cyclase toxin, filamentous hemagglutinin, or pertussis toxin had decreased abilities to enter and to survive inside macrophages. The results suggest that the internalization process, as well as intracellular survival, is virulence dependent and that mutations which inactivate expression of virulence factors may affect both. The ability of B. pertussis to enter and persist inside macrophages may be important not only for survival of the bacteria but also in the pathogenesis of whooping cough.
منابع مشابه
Regulation of pertussis toxin and lipopolysaccharide levels of Bordetella pertussis 134 in response to modulators
Whooping cough (pertussis) is a highly contagious disease of the human respiratory tract, which is caused by Bordetella pertussis. Reemerge of pertussis in some highly immunized populations and divergency in gene order among several B. pertussis strains promoted this research to study the change of pertussis toxin (PT) and lipopolysacharide levels in response to the different environments. Th...
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عنوان ژورنال:
- Infection and immunity
دوره 60 11 شماره
صفحات -
تاریخ انتشار 1992