The Antibacterial Lectin RegIIIγ Promotes the Spatial Segregation of Microbiota and Host in the Intestine

作者：Shipra Vaishnava, Miwako Yamamoto, Kari M. Severson, Kelly A. Ruhn, Xiaofei Yu, Omry Koren, Ruth E. Ley, Edward K. Wakeland, Lora V. Hooper · 发表于：Science · 年份：2011 · DOI：10.1126/science.1209791 · 被引用次数：1424 · 研究领域：Gut microbiota and health、Clostridium difficile and Clostridium perfringens research、Escherichia coli research studies

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 intestinal epithelial surface. Loss of host-bacterial segregation in RegIIIγ(-/-) 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 RegIIIγ is a fundamental immune mechanism that promotes host-bacterial mutualism by regulating the spatial relationships between microbiota and host.