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TLR4-mediated expulsion of bacteria from infected bladder epithelial cells.

ABSTRACT: Uropathogenic Escherichia coli invade bladder epithelial cells (BECs) by direct entry into specialized cAMP regulated exocytic compartments. Remarkably, a significant number of these intracellular bacteria are subsequently expelled in a nonlytic and piecemeal fashion by infected BECs. Here, we report that expulsion of intracellular E. coli by infected BECs is initiated by the pattern recognition receptor, Toll-like receptor (TLR)4, after activation by LPS. Also, we reveal that caveolin-1, Rab27b, PKA, and MyRIP are components of the exocytic compartment, and that they form a complex involved in the exocytosis of bacteria. This capacity of TLR4 to mediate the expulsion of intracellular bacteria from infected cells represents a previously unrecognized function for this innate immune receptor.

SUBMITTER: Song J

PROVIDER: S-EPMC2736405 | biostudies-literature | 2009 Sep

REPOSITORIES: biostudies-literature

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TLR4-mediated expulsion of bacteria from infected bladder epithelial cells.

Song Jeongmin J Bishop Brian L BL Li Guojie G Grady Richard R Stapleton Ann A Abraham Soman N SN

Proceedings of the National Academy of Sciences of the United States of America 20090817 35

Uropathogenic Escherichia coli invade bladder epithelial cells (BECs) by direct entry into specialized cAMP regulated exocytic compartments. Remarkably, a significant number of these intracellular bacteria are subsequently expelled in a nonlytic and piecemeal fashion by infected BECs. Here, we report that expulsion of intracellular E. coli by infected BECs is initiated by the pattern recognition receptor, Toll-like receptor (TLR)4, after activation by LPS. Also, we reveal that caveolin-1, Rab27b ...[more]

PMID: 19706440

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