title: Oral tolerance is inducible during active dextran sulfate sodium-induced colitis.
abstract: OBJECTIVE
  To investigate whether oral tolerance is inducible during the active phase of dextran sulfate sodium (DSS)-induced colitis.
  
  
  METHODS
  Colitis was induced in 6- to 8-wk-old female BALB/c mice by the administration of 2% DSS. To induce oral tolerance, mice that received water with DSS [DSS (+)] and mice that received autoclaved water [DSS (-)] were intragastrically (i.g.) administered ovalbumin (OVA) as a tolerogen before systemic challenge with OVA. Following this, serum levels of OVA-specific IgE antibodies were measured. In mice with active colitis, CD4(+)CD25(+)Foxp3(+) cell and B10 cell frequencies were evaluated using flow cytometry. Cytokine mRNA expression profiles were evaluated by reverse transcription real-time polymerase chain reaction.
  
  
  RESULTS
  Regardless of the presence of DSS colitis, OVA-specific immunoglobulin E concentrations were significantly reduced in mice that were i.g. administered OVA compared to mice that were i.g. administered PBS [DSS (+): 4.4 (4.2-9.5) ng/mL vs 83.9 (66.1-123.2) ng/mL, P < 0.01; DSS (-): 27.7 (0.1-54.5) ng/mL vs 116.5 (80.6-213.6) ng/mL, P < 0.01]. These results demonstrated that oral tolerance was induced in both the presence and absence of colitis. In the spleen and mesenteric lymph nodes (MLN), the frequencies of CD4(+)CD25(+)Foxp3(+) cells and B10 cells, both of which are associated with oral tolerance, did not significantly change. In the spleen, interferon-γ mRNA expression significantly decreased in mice with colitis [DSS (+): 0.42 (0.31-0.53) vs DSS (-): 1.00 (0.84-1.39), P < 0.01]. The expression levels of other cytokines did not significantly change.
  
  
  CONCLUSIONS
  Oral tolerance is inducible during active DSS colitis. The stability of regulatory cell populations in the spleen and MLN in colitis might correlate with these results.
authors.affiliation: Satoshi Ino, Chikara Kohda, Kosuke Takeshima, Hiroki Ishikawa, Kazuo Tanaka, Department of Microbiology and Immunology, School of Medicine, Showa University, Tokyo 142-8555, Japan.
authors.forename: Satoshi
authors.initials: S
authors.lastname: Ino
authors.affiliation: Satoshi Ino, Chikara Kohda, Kosuke Takeshima, Hiroki Ishikawa, Kazuo Tanaka, Department of Microbiology and Immunology, School of Medicine, Showa University, Tokyo 142-8555, Japan.
authors.forename: Chikara
authors.initials: C
authors.lastname: Kohda
authors.affiliation: Satoshi Ino, Chikara Kohda, Kosuke Takeshima, Hiroki Ishikawa, Kazuo Tanaka, Department of Microbiology and Immunology, School of Medicine, Showa University, Tokyo 142-8555, Japan.
authors.forename: Kosuke
authors.initials: K
authors.lastname: Takeshima
authors.affiliation: Satoshi Ino, Chikara Kohda, Kosuke Takeshima, Hiroki Ishikawa, Kazuo Tanaka, Department of Microbiology and Immunology, School of Medicine, Showa University, Tokyo 142-8555, Japan.
authors.forename: Hiroki
authors.initials: H
authors.lastname: Ishikawa
authors.affiliation: Satoshi Ino, Chikara Kohda, Kosuke Takeshima, Hiroki Ishikawa, Kazuo Tanaka, Department of Microbiology and Immunology, School of Medicine, Showa University, Tokyo 142-8555, Japan.
authors.forename: Tomoko
authors.initials: T
authors.lastname: Norose
authors.affiliation: Satoshi Ino, Chikara Kohda, Kosuke Takeshima, Hiroki Ishikawa, Kazuo Tanaka, Department of Microbiology and Immunology, School of Medicine, Showa University, Tokyo 142-8555, Japan.
authors.forename: Toshiko
authors.initials: T
authors.lastname: Yamochi
authors.affiliation: Satoshi Ino, Chikara Kohda, Kosuke Takeshima, Hiroki Ishikawa, Kazuo Tanaka, Department of Microbiology and Immunology, School of Medicine, Showa University, Tokyo 142-8555, Japan.
authors.forename: Masafumi
authors.initials: M
authors.lastname: Takimoto
authors.affiliation: Satoshi Ino, Chikara Kohda, Kosuke Takeshima, Hiroki Ishikawa, Kazuo Tanaka, Department of Microbiology and Immunology, School of Medicine, Showa University, Tokyo 142-8555, Japan.
authors.forename: Hiroshi
authors.initials: H
authors.lastname: Takahashi
authors.affiliation: Satoshi Ino, Chikara Kohda, Kosuke Takeshima, Hiroki Ishikawa, Kazuo Tanaka, Department of Microbiology and Immunology, School of Medicine, Showa University, Tokyo 142-8555, Japan.
authors.forename: Kazuo
authors.initials: K
authors.lastname: Tanaka
keywords: Cytokine; Dextran sulfate sodium colitis; Oral tolerance; Regulatory B cell; Regulatory T cell