Abstract:
:Salmonella enterica serovar Typhi can colonize the gallbladder and persist in an asymptomatic carrier state that is frequently associated with the presence of gallstones. We have shown that salmonellae form bile-mediated biofilms on human gallstones and cholesterol-coated surfaces in vitro. Here, we test the hypothesis that biofilms on cholesterol gallbladder stones facilitate typhoid carriage in mice and men. Naturally resistant (Nramp1(+/+)) mice fed a lithogenic diet developed cholesterol gallstones that supported biofilm formation during persistent serovar Typhimurium infection and, as a result, demonstrated enhanced fecal shedding and enhanced colonization of gallbladder tissue and bile. In typhoid endemic Mexico City, 5% of enrolled cholelithiasis patients carried serovar Typhi, and bacterial biofilms could be visualized on gallstones from these carriers whereas significant biofilms were not detected on gallstones from Escherichia coli infected gallbladders. These findings offer direct evidence that gallstone biofilms occur in humans and mice, which facilitate gallbladder colonization and shedding.
journal_name
Proc Natl Acad Sci U S Aauthors
Crawford RW,Rosales-Reyes R,Ramírez-Aguilar Mde L,Chapa-Azuela O,Alpuche-Aranda C,Gunn JSdoi
10.1073/pnas.1000862107subject
Has Abstractpub_date
2010-03-02 00:00:00pages
4353-8issue
9eissn
0027-8424issn
1091-6490pii
1000862107journal_volume
107pub_type
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