title: Active suppression of intestinal CD4(+)TCRαβ(+) T-lymphocyte maturation during the postnatal period.
abstract: Priming of the mucosal immune system during the postnatal period substantially influences host-microbial interaction and susceptibility to immune-mediated diseases in adult life. The underlying mechanisms are ill defined. Here we show that shortly after birth, CD4 T cells populate preformed lymphoid structures in the small intestine and quickly acquire a distinct transcriptional profile. T-cell recruitment is independent of microbial colonization and innate or adaptive immune stimulation but requires β7 integrin expression. Surprisingly, neonatal CD4 T cells remain immature throughout the postnatal period under homeostatic conditions but undergo maturation and gain effector function on barrier disruption. Maternal SIgA and regulatory T cells act in concert to prevent immune stimulation and maintain the immature phenotype of CD4 T cells in the postnatal intestine during homeostasis. Active suppression of CD4 T-cell maturation during the postnatal period might contribute to prevent auto-reactivity, sustain a broad TCR repertoire and establish life-long immune homeostasis.
authors.affiliation: 1] Institute of Medical Microbiology and Hospital Epidemiology, Hannover Medical School, Carl-Neuberg-Straße 1, 30625 Hannover, Germany [2] Institute of Medical Microbiology, RWTH University Hospital, Pauwelsstraße 30, 52074 Aachen, Germany.
authors.forename: Natalia
authors.initials: N
authors.lastname: Torow
authors.affiliation: Institute of Immunology, Hannover Medical School, Hannover, Carl-Neuberg-Straße 1, 30625 Hannover, Germany.
authors.forename: Kai
authors.initials: K
authors.lastname: Yu
authors.affiliation: Institute of Medical Microbiology and Hospital Epidemiology, Hannover Medical School, Carl-Neuberg-Straße 1, 30625 Hannover, Germany.
authors.forename: Kasra
authors.initials: K
authors.lastname: Hassani
authors.affiliation: Institute of Infection Immunology, TWINCORE, Centre for Experimental and Clinical Infection Research, a joint venture between the Medical School, Hannover (MHH) and the Helmholtz Centre for Infection Research (HZI), Feodor-Lynen-Straße 7, 30625 Hannover, Germany.
authors.forename: Jenny
authors.initials: J
authors.lastname: Freitag
authors.affiliation: Institute of Immunology, Hannover Medical School, Hannover, Carl-Neuberg-Straße 1, 30625 Hannover, Germany.
authors.forename: Olga
authors.initials: O
authors.lastname: Schulz
authors.affiliation: Institute for Laboratory Animal Science, Hannover Medical School, Hannover, Carl-Neuberg-Straße 1, 30625 Hannover, Germany.
authors.forename: Marijana
authors.initials: M
authors.lastname: Basic
authors.affiliation: Department of Molecular Immunology, Helmholtz Centre for Infection Research, Inhoffenstraße 7, 38124 Braunschweig, Germany.
authors.forename: Anne
authors.initials: A
authors.lastname: Brennecke
authors.affiliation: Institute of Infection Immunology, TWINCORE, Centre for Experimental and Clinical Infection Research, a joint venture between the Medical School, Hannover (MHH) and the Helmholtz Centre for Infection Research (HZI), Feodor-Lynen-Straße 7, 30625 Hannover, Germany.
authors.forename: Tim
authors.initials: T
authors.lastname: Sparwasser
authors.affiliation: Department of Pediatrics, RWTH Aachen University Hospital, Pauwelsstraße 30, 52074 Aachen, Germany.
authors.forename: Norbert
authors.initials: N
authors.lastname: Wagner
authors.affiliation: Institute for Laboratory Animal Science, Hannover Medical School, Hannover, Carl-Neuberg-Straße 1, 30625 Hannover, Germany.
authors.forename: André
authors.initials: A
authors.lastname: Bleich
authors.affiliation: Institute of Infection Immunology, TWINCORE, Centre for Experimental and Clinical Infection Research, a joint venture between the Medical School, Hannover (MHH) and the Helmholtz Centre for Infection Research (HZI), Feodor-Lynen-Straße 7, 30625 Hannover, Germany.
authors.forename: Matthias
authors.initials: M
authors.lastname: Lochner
authors.affiliation: Department of Molecular Immunology, Helmholtz Centre for Infection Research, Inhoffenstraße 7, 38124 Braunschweig, Germany.
authors.forename: Siegfried
authors.initials: S
authors.lastname: Weiss
authors.affiliation: Institute of Immunology, Hannover Medical School, Hannover, Carl-Neuberg-Straße 1, 30625 Hannover, Germany.
authors.forename: Reinhold
authors.initials: R
authors.lastname: Förster
authors.affiliation: 1] Institute of Immunology, Hannover Medical School, Hannover, Carl-Neuberg-Straße 1, 30625 Hannover, Germany [2] Institute of Molecular Medicine RWTH Aachen University Hospital, Pauwelsstraße 30, 52074 Aachen, Germany.
authors.forename: Oliver
authors.initials: O
authors.lastname: Pabst
authors.affiliation: 1] Institute of Medical Microbiology and Hospital Epidemiology, Hannover Medical School, Carl-Neuberg-Straße 1, 30625 Hannover, Germany [2] Institute of Medical Microbiology, RWTH University Hospital, Pauwelsstraße 30, 52074 Aachen, Germany.
authors.forename: Mathias W
authors.initials: MW
authors.lastname: Hornef
mesh_terms: D000818:Animals; D000831:Animals, Newborn; D015496:CD4-Positive T-Lymphocytes / Q000502:physiology*; D048788:Growth and Development / Q000276:immunology*; D018928:Immunity, Mucosal; D016130:Immunophenotyping; D007422:Intestines / Q000276:immunology* / Q000382:microbiology; D008822:Mice, Transgenic