title: Normalization of Host Intestinal Mucus Layers Requires Long-Term Microbial Colonization.
abstract: The intestinal mucus layer provides a barrier limiting bacterial contact with the underlying epithelium. Mucus structure is shaped by intestinal location and the microbiota. To understand how commensals modulate gut mucus, we examined mucus properties under germ-free (GF) conditions and during microbial colonization. Although the colon mucus organization of GF mice was similar to that of conventionally raised (Convr) mice, the GF inner mucus layer was penetrable to bacteria-sized beads. During colonization, in which GF mice were gavaged with Convr microbiota, the small intestine mucus required 5 weeks to be normally detached and colonic inner mucus 6 weeks to become impenetrable. The composition of the small intestinal microbiota during colonization was similar to Convr donors until 3 weeks, when Bacteroides increased, Firmicutes decreased, and segmented filamentous bacteria became undetectable. These findings highlight the dynamics of mucus layer development and indicate that studies of mature microbe-mucus interactions should be conducted weeks after colonization.
authors.affiliation: Department of Medical Biochemistry, University of Gothenburg, SE-405 30 Gothenburg, Sweden.
authors.forename: Malin E V
authors.initials: ME
authors.lastname: Johansson
authors.affiliation: Department of Medical Biochemistry, University of Gothenburg, SE-405 30 Gothenburg, Sweden.
authors.forename: Hedvig E
authors.initials: HE
authors.lastname: Jakobsson
authors.affiliation: Department of Medical Biochemistry, University of Gothenburg, SE-405 30 Gothenburg, Sweden.
authors.forename: Jessica
authors.initials: J
authors.lastname: Holmén-Larsson
authors.affiliation: Department of Medical Biochemistry, University of Gothenburg, SE-405 30 Gothenburg, Sweden.
authors.forename: André
authors.initials: A
authors.lastname: Schütte
authors.affiliation: Department of Medical Biochemistry, University of Gothenburg, SE-405 30 Gothenburg, Sweden.
authors.forename: Anna
authors.initials: A
authors.lastname: Ermund
authors.affiliation: Department of Medical Biochemistry, University of Gothenburg, SE-405 30 Gothenburg, Sweden.
authors.forename: Ana M
authors.initials: AM
authors.lastname: Rodríguez-Piñeiro
authors.affiliation: Department of Medical Biochemistry, University of Gothenburg, SE-405 30 Gothenburg, Sweden.
authors.forename: Liisa
authors.initials: L
authors.lastname: Arike
authors.affiliation: Department of Medical Biochemistry, University of Gothenburg, SE-405 30 Gothenburg, Sweden.
authors.forename: Catharina
authors.initials: C
authors.lastname: Wising
authors.affiliation: Department of Medical Biochemistry, University of Gothenburg, SE-405 30 Gothenburg, Sweden.
authors.forename: Frida
authors.initials: F
authors.lastname: Svensson
authors.affiliation: Department of Molecular and Clinical Medicine, University of Gothenburg, SE-413 45 Gothenburg, Sweden.
authors.forename: Fredrik
authors.initials: F
authors.lastname: Bäckhed
authors.affiliation: Department of Medical Biochemistry, University of Gothenburg, SE-405 30 Gothenburg, Sweden. Electronic address: gunnar.hansson@medkem.gu.se.
authors.forename: Gunnar C
authors.initials: GC
authors.lastname: Hansson
mesh_terms: D000818:Animals; D001424:Bacterial Infections / Q000382:microbiology*; D001439:Bacteroides / Q000254:growth & development*; D000068536:Bacillota / Q000254:growth & development*; D000069196:Gastrointestinal Microbiome; D005856:Germ-Free Life; D007413:Intestinal Mucosa / Q000382:microbiology*; D051379:Mice; D055262:Mucin-2 / Q000378:metabolism
chemical_list: C524626:Muc2 protein, mouse; D055262:Mucin-2