TY - JOUR T1 - Gut immune maturation depends on colonization with a host-specific microbiota JF - Cell Y1 - 2012 A1 - Chung, Hachung A1 - Pamp, Sünje J A1 - Hill, Jonathan A A1 - Surana, Neeraj K A1 - Edelman, Sanna M A1 - Troy, Erin B A1 - Reading, Nicola C A1 - Villablanca, Eduardo J A1 - Wang, Sen A1 - Mora, Jorge R A1 - Umesaki, Yoshinori A1 - Mathis, Diane A1 - Benoist, Christophe A1 - Relman, David A A1 - Kasper, Dennis L KW - Animals KW - Bacteria KW - Cell Proliferation KW - Female KW - Germ-Free Life KW - Humans KW - Immunity, Innate KW - Intestines KW - Male KW - Metagenome KW - Mice KW - Rats KW - Rats, Sprague-Dawley KW - Salmonella Infections KW - Species Specificity KW - Specific Pathogen-Free Organisms KW - symbiosis KW - T-Lymphocytes AB - Gut microbial induction of host immune maturation exemplifies host-microbe mutualism. We colonized germ-free (GF) mice with mouse microbiota (MMb) or human microbiota (HMb) to determine whether small intestinal immune maturation depends on a coevolved host-specific microbiota. Gut bacterial numbers and phylum abundance were similar in MMb and HMb mice, but bacterial species differed, especially the Firmicutes. HMb mouse intestines had low levels of CD4(+) and CD8(+) T cells, few proliferating T cells, few dendritic cells, and low antimicrobial peptide expression--all characteristics of GF mice. Rat microbiota also failed to fully expand intestinal T cell numbers in mice. Colonizing GF or HMb mice with mouse-segmented filamentous bacteria (SFB) partially restored T cell numbers, suggesting that SFB and other MMb organisms are required for full immune maturation in mice. Importantly, MMb conferred better protection against Salmonella infection than HMb. A host-specific microbiota appears to be critical for a healthy immune system. VL - 149 IS - 7 U1 - http://www.ncbi.nlm.nih.gov/pubmed/22726443?dopt=Abstract ER -