title: Intestinal barrier dysfunction develops at the onset of experimental autoimmune encephalomyelitis, and can be induced by adoptive transfer of auto-reactive T cells.
abstract: Multiple sclerosis (MS) is a chronic inflammatory demyelinating disease of the central nervous system with a pathogenesis involving a dysfunctional blood-brain barrier and myelin-specific, autoreactive T cells. Although the commensal microbiota seems to affect its pathogenesis, regulation of the interactions between luminal antigens and mucosal immune elements remains unclear. Herein, we investigated whether the intestinal mucosal barrier is also targeted in this disease. Experimental autoimmune encephalomyelitis (EAE), the prototypic animal model of MS, was induced either by active immunization or by adoptive transfer of autoreactive T cells isolated from these mice. We show increased intestinal permeability, overexpression of the tight junction protein zonulin and alterations in intestinal morphology (increased crypt depth and thickness of the submucosa and muscularis layers). These intestinal manifestations were seen at 7 days (i.e., preceding the onset of neurological symptoms) and at 14 days (i.e., at the stage of paralysis) after immunization. We also demonstrate an increased infiltration of proinflammatory Th1/Th17 cells and a reduced regulatory T cell number in the gut lamina propria, Peyer's patches and mesenteric lymph nodes. Adoptive transfer to healthy mice of encephalitogenic T cells, isolated from EAE-diseased animals, led to intestinal changes similar to those resulting from the immunization procedure. Our findings show that disruption of intestinal homeostasis is an early and immune-mediated event in EAE. We propose that this intestinal dysfunction may act to support disease progression, and thus represent a potential therapeutic target in MS. In particular, an increased understanding of the regulation of tight junctions at the blood-brain barrier and in the intestinal wall may be crucial for design of future innovative therapies.
authors.affiliation: Department of Clinical Sciences, Clinical Research Centre, Surgery Research Unit, Lund University, Malmö, Sweden; Department of Biology, Lund University, Lund, Sweden.
authors.forename: Mehrnaz
authors.initials: M
authors.lastname: Nouri
authors.affiliation: ImmuneBiotech AB, Lund Life Science Incubator, Medicon Village, Lund, Sweden; Department of Laboratory Medicine, Section of Medical Microbiology, Lund University, Malmö, Sweden.
authors.forename: Anders
authors.initials: A
authors.lastname: Bredberg
authors.affiliation: Department of Biology, Lund University, Lund, Sweden.
authors.forename: Björn
authors.initials: B
authors.lastname: Weström
authors.affiliation: Department of Biology, Lund University, Lund, Sweden; ImmuneBiotech AB, Lund Life Science Incubator, Medicon Village, Lund, Sweden.
authors.forename: Shahram
authors.initials: S
authors.lastname: Lavasani
mesh_terms: D019264:Adoptive Transfer; D000818:Animals; D001812:Blood-Brain Barrier / Q000276:immunology; D002772:Cholera Toxin / Q000096:biosynthesis; D003711:Demyelinating Diseases / Q000276:immunology / Q000473:pathology; D004681:Encephalomyelitis, Autoimmune, Experimental / Q000276:immunology* / Q000378:metabolism / Q000473:pathology; D006242:Haptoglobins; D006801:Humans; D007413:Intestinal Mucosa / Q000276:immunology* / Q000473:pathology; D051379:Mice; D009103:Multiple Sclerosis / Q000276:immunology* / Q000378:metabolism / Q000473:pathology; D011498:Protein Precursors; D050378:T-Lymphocytes, Regulatory / Q000276:immunology; D018417:Th1 Cells / Q000276:immunology; D058504:Th17 Cells / Q000276:immunology
chemical_list: D006242:Haptoglobins; D011498:Protein Precursors; C408043:zonulin; D002772:Cholera Toxin