title: Understanding Luminal Microorganisms and Their Potential Effectiveness in Treating Intestinal Inflammation.
abstract: The human intestine contains 10¹⁴ bacteria, which outnumber the mammalian cells 10-fold. Certain other commensal or infectious agents, like helminthic parasites, become members of this microbial ecosystem, especially in populations living under less hygienic conditions. Intestinal microbes, also called the microbiome or microbiota, shape the host immune reactivity to self and nonself throughout life. Changes in microbiome composition may impair the maturation of immune regulatory pathways and predispose the host to develop various forms of inflammatory disorders, like Crohn's disease or ulcerative colitis. The microbiome is also critical to successful transplantation of organs or grafts. After allogeneic hematopoietic stem cell transplantation, when the new donor cells, such as T lymphocytes learn to discriminate "the new self from nonself" in the transplant recipient, they need healthy microbiota-derived signals to preserve the immune homeostasis. Restoring microbiota through intestinal delivery of bacterial strains, helminths, fecal microbiota transplantation, or stool substitutes have the potential to improve and correct aberrant immune reactivity in various disorders.
authors.affiliation: *Division of Gastroenterology and Hepatology, Department of Internal Medicine, Carver College of Medicine, University of Iowa, Iowa City, Iowa; †Division of Blood and Marrow Transplantation, Department of Pediatrics, Masonic Medical Center, University of Minnesota, Minneapolis, Minnesota; ‡Division of Infectious Diseases, Department of Internal Medicine, Carver College of Medicine, University of Iowa, Iowa City, Iowa; §Division of Hematology, Oncology and Bone Marrow Transplantation, Department of Internal Medicine, Carver College of Medicine, University of Iowa, Iowa City, Iowa; and ‖Department of Veterinary Microbiology, Iowa State University, Ames, Iowa.
authors.forename: M Nedim
authors.initials: MN
authors.lastname: Ince
authors.forename: Bruce R
authors.initials: BR
authors.lastname: Blazar
authors.forename: Michael B
authors.initials: MB
authors.lastname: Edmond
authors.forename: Guido
authors.initials: G
authors.lastname: Tricot
authors.forename: Michael J
authors.initials: MJ
authors.lastname: Wannemuehler
mesh_terms: D000818:Animals; D006801:Humans; D007249:Inflammation / Q000628:therapy*; D007422:Intestines / Q000276:immunology / Q000382:microbiology*; D064307:Microbiota