title: How colonization by microbiota in early life shapes the immune system.
abstract: Microbial colonization of mucosal tissues during infancy plays an instrumental role in the development and education of the host mammalian immune system. These early-life events can have long-standing consequences: facilitating tolerance to environmental exposures or contributing to the development of disease in later life, including inflammatory bowel disease, allergy, and asthma. Recent studies have begun to define a critical period during early development in which disruption of optimal host-commensal interactions can lead to persistent and in some cases irreversible defects in the development and training of specific immune subsets. Here, we discuss the role of early-life education of the immune system during this "window of opportunity," when microbial colonization has a potentially critical impact on human health and disease.
authors.affiliation: Division of Gastroenterology, Hepatology, and Endoscopy, Department of Medicine, Brigham and Women's Hospital, Harvard Medical School, Boston, MA, USA.
authors.forename: Thomas
authors.initials: T
authors.lastname: Gensollen
authors.affiliation: Division of Gastroenterology, Hepatology, and Endoscopy, Department of Medicine, Brigham and Women's Hospital, Harvard Medical School, Boston, MA, USA.
authors.forename: Shankar S
authors.initials: SS
authors.lastname: Iyer
authors.affiliation: Division of Immunology, Department of Microbiology and Immunobiology, Harvard Medical School, Boston, MA, USA.
authors.forename: Dennis L
authors.initials: DL
authors.lastname: Kasper
authors.affiliation: Division of Gastroenterology, Hepatology, and Endoscopy, Department of Medicine, Brigham and Women's Hospital, Harvard Medical School, Boston, MA, USA. rblumberg@partners.org.
authors.forename: Richard S
authors.initials: RS
authors.lastname: Blumberg
mesh_terms: D000367:Age Factors; D001249:Asthma / Q000276:immunology / Q000382:microbiology; D006801:Humans; D006967:Hypersensitivity / Q000276:immunology / Q000382:microbiology; D007107:Immune System / Q000276:immunology*; D007108:Immune Tolerance; D007231:Infant, Newborn; D015212:Inflammatory Bowel Diseases / Q000276:immunology / Q000382:microbiology; D007413:Intestinal Mucosa / Q000276:immunology* / Q000382:microbiology*; D064307:Microbiota / Q000276:immunology*; D055611:Natural Killer T-Cells / Q000276:immunology; D013559:Symbiosis; D016176:T-Lymphocyte Subsets / Q000276:immunology