title: Regulatory T cells may participate in Helicobacter pylori persistence in gastric MALT lymphoma: lessons from an animal model.
abstract: It has been postulated that the emergence of autoimmune gastritis in neonatal thymectomised (d3Tx) BALB/c mice may be a consequence of post-surgery deficit in Tregs. In this study, previously obtained samples from d3Tx mice were used in order to determine whether thymectomy creates a deficit in this T cell subset thereby allowing the emergence of autoimmune phenomena as a prerequisite for GML. The splenic Treg reserve and the local recruitment of these cells in the gastric mucosa were investigated using complementary molecular and immunohistochemistry approaches. Higher Foxp3/CD3 ratios were found in the spleen of non-infected d3Tx mice compared to non-thymectomised (NTx) controls. These results indicate a relative enrichment of Tregs following thymectomy in adult mice. The absence of Treg depletion in d3Tx mice is in line with the absence of auto-immune gastritis in non-infected d3Tx mice. Higher levels of T cell and Treg infiltration were also found in the stomach of GML-developing d3Tx mice versus NTx mice. Surprisingly, inflammatory scores inversely correlated with the bacterial inoculum. The presence of a small Treg containing compartment among gastric biopsies of GML developing d3Tx mice may play a role in perseverance of a minimal bacterial numbers thereby maintaining an antigen-dependent stimulation and proliferation.
authors.affiliation: University Bordeaux, Bacteriology Laboratory, Bordeaux, France.|INSERM U853, Bordeaux, France.
authors.forename: Amandine Marine
authors.initials: AM
authors.lastname: Laur
authors.affiliation: University Bordeaux, Bacteriology Laboratory, Bordeaux, France.|INSERM U853, Bordeaux, France.
authors.forename: Pauline
authors.initials: P
authors.lastname: Floch
authors.affiliation: University Bordeaux, Bacteriology Laboratory, Bordeaux, France.|INSERM U853, Bordeaux, France.
authors.forename: Lucie
authors.initials: L
authors.lastname: Chambonnier
authors.affiliation: University Bordeaux, Bacteriology Laboratory, Bordeaux, France.
authors.forename: Lucie
authors.initials: L
authors.lastname: Benejat
authors.affiliation: Institute for Glycomics, Griffith University, Nathan QLD, Australia.
authors.forename: Victoria
authors.initials: V
authors.lastname: Korolik
authors.affiliation: University Bordeaux, EA 2406, Bordeaux, France.
authors.forename: Alban
authors.initials: A
authors.lastname: Giese
authors.affiliation: University Bordeaux, EA 2406, Bordeaux, France.
authors.forename: Pierre
authors.initials: P
authors.lastname: Dubus
authors.affiliation: University Bordeaux, Bacteriology Laboratory, Bordeaux, France.|INSERM U853, Bordeaux, France.
authors.forename: Francis
authors.initials: F
authors.lastname: Mégraud
authors.affiliation: Unit for Biology of Lymphocyte Populations, Immunology Department, Institut Pasteur and CIMI, Unity of Treg Biology and Therapy, University of Pierre & Marie Curie, Paris, France.
authors.forename: Antonio
authors.initials: A
authors.lastname: Bandeira
authors.affiliation: University Bordeaux, Bacteriology Laboratory, Bordeaux, France.|INSERM U853, Bordeaux, France.
authors.forename: Philippe
authors.initials: P
authors.lastname: Lehours
mesh_terms: D000818:Animals; D004195:Disease Models, Animal; D005753:Gastric Mucosa / Q000276:immunology* / Q000382:microbiology / Q000473:pathology; D016481:Helicobacter Infections / Q000276:immunology* / Q000382:microbiology / Q000473:pathology; D016480:Helicobacter pylori / Q000276:immunology*; D007124:Immunoenzyme Techniques; D018442:Lymphoma, B-Cell, Marginal Zone / Q000276:immunology* / Q000382:microbiology / Q000473:pathology; D008228:Lymphoma, Non-Hodgkin / Q000276:immunology* / Q000382:microbiology / Q000473:pathology; D051379:Mice; D012333:RNA, Messenger / Q000235:genetics; D060888:Real-Time Polymerase Chain Reaction; D020133:Reverse Transcriptase Polymerase Chain Reaction; D013274:Stomach Neoplasms / Q000276:immunology* / Q000382:microbiology / Q000473:pathology; D050378:T-Lymphocytes, Regulatory / Q000276:immunology*
chemical_list: D012333:RNA, Messenger
keywords: Helicobacter pylori; MALT lymphoma; animal model; regulatory T cell