The role of dendritic cells, B cells, and M cells in gut-oriented immune responses.
Although induction of T cell responses to fed Ag (oral tolerance) is thought to happen within the organized lymphoid tissue of the gut, we found that mice lacking Peyer's patches, B cells, and the specialized Ag-handling M cells had no defect in the induction of T cell responses to fed Ag, whether assayed in vitro by T cell proliferation or cytokine production, or in vivo by delayed-type hypersensitivity or bystander suppression against mycobacterial Ags in CFA. Feeding of Ag had a major influence on dendritic cells from fed wild-type or muMT mice, such that these APCs were able to elicit a different class of response from naive T cells in vitro. These results suggest that systemic immune responses to soluble oral Ags do not require an organized gut-associated lymphoid tissue but are most likely induced by gut-conditioned dendritic cells that function both to initiate the gut-oriented response and to impart the characteristic features that discriminate it from responses induced parenterally.
Alpan
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O
Ghost Lab, Section on T-Cell Tolerance and Memory, Laboratory of Cellular and Molecular Immunology, National Institutes of Allergy and Infectious Diseases, National Institutes of Health, Bethesda, MD 20892, USA. OAlpan@nih.gov
Rudomen
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Matzinger
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P
D000284:Administration, Oral; D000818:Animals; D000938:Antigen-Presenting Cells / Q000276:immunology; D000941:Antigens / Q000008:administration & dosage* / Q000276:immunology*; D001402:B-Lymphocytes / Q000276:immunology*; D003713:Dendritic Cells / Q000276:immunology*; D004032:Diet; D004306:Dose-Response Relationship, Immunologic; D006968:Hypersensitivity, Delayed / Q000235:genetics / Q000276:immunology; D007108:Immune Tolerance / Q000235:genetics; D007148:Immunoglobulin mu-Chains / Q000235:genetics; D007271:Injections, Intradermal; D007399:Interphase / Q000235:genetics / Q000276:immunology; D007413:Intestinal Mucosa / Q000166:cytology* / Q000276:immunology* / Q000473:pathology; D008231:Lymphopenia / Q000235:genetics / Q000276:immunology / Q000473:pathology; D051379:Mice; D008805:Mice, Inbred A; D008810:Mice, Inbred C57BL; D018345:Mice, Knockout; D008822:Mice, Transgenic; D010047:Ovalbumin / Q000008:administration & dosage / Q000276:immunology; D006377:T-Lymphocytes, Helper-Inducer / Q000276:immunology
D000941:Antigens; D007148:Immunoglobulin mu-Chains; D010047:Ovalbumin