title: Enteroantigen-presenting B cells efficiently stimulate CD4(+) T cells in vitro.
abstract: BACKGROUND
  Presentation of enterobacterial antigens by antigen-presenting cells and activation of enteroantigen-specific CD4(+) T cells are considered crucial steps in inflammatory bowel disease (IBD) pathology. The detrimental effects of such CD4(+) T cells have been thoroughly demonstrated in models of colitis. Also, we have previously established an in vitro assay where murine enteroantigen-specific colitogenic CD4(+) CD25(-) T cells are activated by splenocytes pulsed with an enterobacterial extract.
  
  
  METHODS
  CD4(+) CD25(-) T cells were stimulated in vitro with various kinds of enterobacterial extract-pulsed antigen-presenting cells. T-helper phenotypes were detected by flow cytometry.
  
  
  RESULTS
  We found that enteroantigen-pulsed splenic B cells possess a significantly higher and more sustained T cell stimulatory capacity than similarly pulsed splenic dendritic cells (DCs) measured by the level of enteroantigen-specific CD4(+) CD25(-) T cell proliferation. In support of this, we observed upregulation of classic maturation markers in B cells following incubation with enterobacterial antigens. Peritoneal and mesenteric lymph node-derived B cells were equally effective as enteroantigen-presenting stimulator cells. B cells greatly expanded the number of stimulated CD4(+) T cells, which acquired a T(H) 2 phenotype. Interestingly, regulatory T cells were primarily activated by enteroantigen-pulsed B cells but not by similarly pulsed DCs.
  
  
  CONCLUSIONS
  We conclude that B cells are superior stimulators of enteroantigen-specific CD4(+) T cells in vitro, favoring T(H) 2 polarization. Thus, enteroantigen-processing and -presentation by B cells instead of by DCs might have opposing consequences for IBD development.
authors: Department of International Health, Immunology and Microbiology, Faculty of Health Sciences, University of Copenhagen, Copenhagen, Denmark. Esbens@sund.ku.dk
authors: Esben Gjerløff Wedebye
authors: EG
authors: Schmidt
authors: Nanna Ny
authors: NN
authors: Kristensen
authors: Mogens Helweg
authors: MH
authors: Claesson
authors: Anders Elm
authors: AE
authors: Pedersen
mesh_terms: D019264:Adoptive Transfer; D000818:Animals; D000938:Antigen-Presenting Cells / Q000276:immunology* / Q000378:metabolism; D000942:Antigens, Bacterial / Q000276:immunology* / Q000378:metabolism; D001402:B-Lymphocytes / Q000276:immunology* / Q000378:metabolism / Q000473:pathology; D015153:Blotting, Western; D015496:CD4-Positive T-Lymphocytes / Q000276:immunology* / Q000378:metabolism; D049109:Cell Proliferation; D003092:Colitis / Q000276:immunology* / Q000378:metabolism / Q000473:pathology; D016207:Cytokines / Q000378:metabolism; D003713:Dendritic Cells / Q000276:immunology / Q000378:metabolism; D004755:Enterobacteriaceae / Q000276:immunology*; D005260:Female; D005434:Flow Cytometry; D051379:Mice; D008807:Mice, Inbred BALB C; D008810:Mice, Inbred C57BL; D016513:Mice, SCID; D050378:T-Lymphocytes, Regulatory / Q000276:immunology* / Q000378:metabolism
chemical_list: D000942:Antigens, Bacterial; D016207:Cytokines