title: Comparison of mucosal B- and T-cell responses in Helicobacter pylori-infected subjects in a developing and a developed country.
abstract: Helicobacter pylori is highly endemic in developing countries, but comparatively little is known about mucosal immune responses to H. pylori in these settings. Therefore, we have compared B- and T-cell responses, with a focus on the gastrointestinal mucosa, in H. pylori-infected adults in a developing (Bangladesh) and a developed (Sweden) country. We found comparable numbers of CD19(+) B cells and CD4 (+)T cells and similar levels of H. pylori-specific IgA antibodies in gastric mucosa from Bangladeshi and Swedish volunteers. However, about threefold higher numbers of CD19(+) B cells and 12-fold increased levels of H. pylori-specific IgA antibodies were found in the duodenum of Bangladeshi subjects. The gastric and duodenal immune responses in Bangladeshi asymptomatic carriers and duodenal ulcer patients were comparable. Bangladeshi subjects had about twofold lower titers of H. pylori-specific IgA and IgG antibodies in the circulation compared with Swedish volunteers. In conclusion, our findings suggest that Bangladeshi individuals have comparable gastric immune responses, but lower systemic antibody responses to H. pylori, compared with Swedish volunteers. Increased inflammation is present in the duodenum of Bangladeshi volunteers, maybe as a result of frequent exposure to enteric infections in these individuals.
authors.affiliation: Department of Microbiology and Immunology, Institute of Biomedicine, The Sahlgrenska Academy at the University of Gothenburg, Gothenburg, Sweden.
authors.forename: Taufiqur Rahman
authors.initials: TR
authors.lastname: Bhuiyan
authors.forename: Firdausi
authors.initials: F
authors.lastname: Qadri
authors.forename: Prodip Kumar
authors.initials: PK
authors.lastname: Bardhan
authors.forename: Mian Mashhud
authors.initials: MM
authors.lastname: Ahmad
authors.forename: Bert
authors.initials: B
authors.lastname: Kindlund
authors.forename: Ann-Mari
authors.initials: AM
authors.lastname: Svennerholm
authors.forename: Anna
authors.initials: A
authors.lastname: Lundgren
mesh_terms: D000293:Adolescent; D000328:Adult; D000818:Animals; D000907:Antibodies, Bacterial / Q000032:analysis / Q000276:immunology; D001402:B-Lymphocytes / Q000276:immunology*; D001459:Bangladesh / Q000453:epidemiology; D019049:Developed Countries; D003906:Developing Countries; D004386:Duodenum / Q000276:immunology; D005260:Female; D016481:Helicobacter Infections / Q000453:epidemiology / Q000276:immunology / Q000382:microbiology; D016480:Helicobacter pylori / Q000276:immunology; D006801:Humans; D018928:Immunity, Mucosal; D007413:Intestinal Mucosa / Q000276:immunology*; D008297:Male; D008875:Middle Aged; D011706:Pyloric Antrum / Q000276:immunology; D013548:Sweden / Q000453:epidemiology; D013601:T-Lymphocytes / Q000276:immunology*
chemical_list: D000907:Antibodies, Bacterial