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The antibacterial lectin RegIIIgamma promotes the spatial segregation of microbiota and host in the intestine.

ABSTRACT: The mammalian intestine is home to ~100 trillion bacteria that perform important metabolic functions for their hosts. The proximity of vast numbers of bacteria to host intestinal tissues raises the question of how symbiotic host-bacterial relationships are maintained without eliciting potentially harmful immune responses. Here, we show that RegIII?, a secreted antibacterial lectin, is essential for maintaining a ~50-micrometer zone that physically separates the microbiota from the small intestinal epithelial surface. Loss of host-bacterial segregation in RegIII?(-/-) mice was coupled to increased bacterial colonization of the intestinal epithelial surface and enhanced activation of intestinal adaptive immune responses by the microbiota. Together, our findings reveal that RegIII? is a fundamental immune mechanism that promotes host-bacterial mutualism by regulating the spatial relationships between microbiota and host.

SUBMITTER: Vaishnava S

PROVIDER: S-EPMC3321924 | biostudies-literature | 2011 Oct

REPOSITORIES: biostudies-literature

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The antibacterial lectin RegIIIgamma promotes the spatial segregation of microbiota and host in the intestine.

Vaishnava Shipra S Yamamoto Miwako M Severson Kari M KM Ruhn Kelly A KA Yu Xiaofei X Koren Omry O Ley Ruth R Wakeland Edward K EK Hooper Lora V LV

Science (New York, N.Y.) 20111001 6053

The mammalian intestine is home to ~100 trillion bacteria that perform important metabolic functions for their hosts. The proximity of vast numbers of bacteria to host intestinal tissues raises the question of how symbiotic host-bacterial relationships are maintained without eliciting potentially harmful immune responses. Here, we show that RegIIIγ, a secreted antibacterial lectin, is essential for maintaining a ~50-micrometer zone that physically separates the microbiota from the small intestin ...[more]

PMID: 21998396

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Dataset Information

The antibacterial lectin RegIIIgamma promotes the spatial segregation of microbiota and host in the intestine.

Publications

The antibacterial lectin RegIIIgamma promotes the spatial segregation of microbiota and host in the intestine.

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