title: Induction of suppressor cells following mucosal presentation of Actinomyces viscosus in mice.
abstract: Mucosal presentation of Actinomyces viscosus results in antigen-specific systemic immune suppression, known as oral tolerance. The aim of the present study was to determine the mechanism by which this oral tolerance is induced. DBA/2 mice were gastrically immunized with A. viscosus. Serum, Peyer's patch (PP) and spleen cells were transferred to syngeneic recipients which were then systemically challenged with the sameiA. viscosus strain. To determine antigen-specificity of cells from gastrically immunized mice, recipients which received immune spleen cells were also challenged with Porphyromonas gingivalis. One week after the last systemic challenge, the delayed type hypersensitivity (DTH) response was determined by footpad swelling and the level of serum IgG, IgA and IgM antibodies to A. viscosus or P. gingivalis measured by an ELISA. No suppression of DTH response or of specific serum antibodies was found in recipients which received serum from gastrically immunized mice. Systemic immune suppression to A. viscosus was observed in recipients which had been transferred with PP cells obtained 2 days but not 4 and 6 days after gastric immunization with A. viscosus. Conversely, suppressed immune response could be seen in recipients transferred with spleen cells obtained 6 days after gastric immunization. The immune response to P. gingivalis remained unaltered in mice transferred with A. viscosus-gastrically immunized cells. The results of the present study suggest that oral tolerance induced by A. viscosus may be mediated by antigen-specific suppressor cells which originate in the PP and then migrate to the spleen.
authors.affiliation: Department of Oral Biology, School of Dental Sciences, and Department of Immunology, School of Medical Sciences, Universiti Sains Malaysia, Kota Bharu, Kelantan, Malaysia. wihaskoro@kb.usm.my
authors.forename: W
authors.initials: W
authors.lastname: Sosroseno
authors.forename: P S
authors.initials: PS
authors.lastname: Bird
authors.forename: E
authors.initials: E
authors.lastname: Gemmell
authors.forename: G J
authors.initials: GJ
authors.lastname: Seymour
mesh_terms: D016924:Actinomyces viscosus / Q000276:immunology*; D000818:Animals; D000907:Antibodies, Bacterial / Q000097:blood; D000942:Antigens, Bacterial / Q000097:blood / Q000276:immunology; D000939:Epitopes / Q000276:immunology; D005260:Female; D006968:Hypersensitivity, Delayed / Q000276:immunology; D007108:Immune Tolerance / Q000276:immunology; D007114:Immunization; D007070:Immunoglobulin A / Q000097:blood; D007074:Immunoglobulin G / Q000097:blood; D007075:Immunoglobulin M / Q000097:blood; D016018:Least-Squares Analysis; D051379:Mice; D008811:Mice, Inbred DBA; D008815:Mice, Inbred Strains; D009061:Mouth Mucosa / Q000276:immunology* / Q000382:microbiology; D010581:Peyer's Patches / Q000276:immunology; D016966:Porphyromonas gingivalis / Q000276:immunology; D013154:Spleen / Q000276:immunology; D050378:T-Lymphocytes, Regulatory / Q000276:immunology*
chemical_list: D000907:Antibodies, Bacterial; D000942:Antigens, Bacterial; D000939:Epitopes; D007070:Immunoglobulin A; D007074:Immunoglobulin G; D007075:Immunoglobulin M