PT - JOURNAL ARTICLE AU - Eduardo J. Contijoch AU - Graham J. Britton AU - Chao Yang AU - Ilaria Mogno AU - Zhihua Li AU - Ruby Ng AU - Sean R. Llewellyn AU - Sheela Hira AU - Crystal Johnson AU - Keren M. Rabinowitz AU - Revital Barkan AU - Iris Dotan AU - Robert P. Hirten AU - Shih-Chen Fu AU - Yuying Luo AU - Nancy Yang AU - Tramy Luong AU - Philippe R. Labrias AU - Sergio A. Lira AU - Inga Peter AU - Ari Grinspan AU - Jose C. Clemente AU - Roman Kosoy AU - Seunghee Kim-Schulze AU - Xiaochen Qin AU - Anabella Castillo AU - Amanda Hurley AU - Ashish Atreja AU - Jason Rogers AU - Farah Fasihuddin AU - Merjona Saliaj AU - Amy Nolan AU - Pamela Reyes-Mercedes AU - Carina Rodriguez AU - Sarah Aly AU - Kenneth Santa-Cruz AU - Lauren A. Peters AU - Mayte Suárez-Fariñas AU - Ruiqi Huang AU - Ke Hao AU - Jun Zhu AU - Bin Zhang AU - Bojan Losic AU - Haritz Irizar AU - Won-Min Song AU - Antonio Di Narzo AU - Wenhui Wang AU - Benjamin L. Cohen AU - Christopher DiMaio AU - David Greenwald AU - Steven Itzkowitz AU - Aimee Lucas AU - James Marion AU - Elana Maser AU - Ryan Ungaro AU - Steven Naymagon AU - Joshua Novak AU - Brijen Shah AU - Thomas Ullman AU - Peter Rubin AU - James George AU - Peter Legnani AU - Shannon E Telesco AU - Joshua R. Friedman AU - Carrie Brodmerkel AU - Scott Plevy AU - Judy Cho AU - Jean-Frederic Colombel AU - Eric Schadt AU - Carmen Argmann AU - Marla Dubinsky AU - Andrew Kasarskis AU - Bruce Sands AU - Jeremiah J. Faith TI - Gut microbiota density influences host physiology and is shaped by host and microbial factors AID - 10.1101/277095 DP - 2018 Jan 01 TA - bioRxiv PG - 277095 4099 - http://biorxiv.org/content/early/2018/07/12/277095.short 4100 - http://biorxiv.org/content/early/2018/07/12/277095.full AB - To identify factors that regulate gut microbiota density and the impact of varied microbiota density on health, we assayed this fundamental ecosystem property in fecal samples across mammals, human disease, and therapeutic interventions. Physiologic features of the host (carrying capacity) and the fitness of the gut microbiota shape microbiota density. Therapeutic manipulation of microbiota density in mice altered host metabolic and immune homeostasis. In humans, gut microbiota density was reduced in Crohn’s disease, ulcerative colitis, and ileal pouch-anal anastomosis. The gut microbiota in recurrent Clostridium difficile infection had lower density and reduced fitness that were restored by fecal microbiota transplantation. Understanding the interplay between microbiota and disease in terms of microbiota density, host carrying capacity, and microbiota fitness provide new insights into microbiome structure and microbiome targeted therapeutics.