Translocation and dissemination of commensal bacteria in post-stroke infection

Dragana Stanley, Linda J. Mason, Kate E. MacKin, Yogitha N. Srikhanta, Dena Lyras, Monica D. Prakash, Kulmira Nurgali, Andres Venegas, Michael D. Hill, Robert J. Moore, Connie H.Y. Wong

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304 Citations (Scopus)


Bacterial infection is highly prevalent in patients who have had a stroke. Despite the potential contribution of micro-aspiration in post-stroke pneumonia, we found that the majority of the microorganisms detected in the patients who developed infections after having a stroke were common commensal bacteria that normally reside in the intestinal tracts. In a mouse model of ischemic stroke, post-stroke infection was only observed in mice that were born and raised in specific-pathogen-free facilities; this was not seen in mice that were born and raised in germ-free facilities. Using high-throughput 16S rRNA gene amplicon sequencing and bioinformatics analyses, we provide evidence demonstrating that the source of the bacteria forming the microbial community in the lungs of post-stroke mice was indeed the host small intestine. Additionally, stroke-induced gut barrier permeability and dysfunction preceded the dissemination of orally inoculated bacteria to peripheral tissues. This study identifies a novel pathway in which stroke promotes the translocation and dissemination of selective strains of bacteria that originated from the host gut microbiota.

Original languageEnglish
Pages (from-to)1277-1284
Number of pages8
JournalNature Medicine
Issue number11
Publication statusPublished - 1 Nov 2016

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