Regulation of immune response in hole body and intestinal mucosa by oral administration of staphylococcal enterotoxin B (SEB)

We have been elucidated that oral SEB administration prevented the onset of DSS induced colitis，and influence of clonal deletion designated by Vβ8T-cells.We evaluated the effect of oral SEB administration on TCRαKO mice.(Experiment1)Simultaneous administration of SEB ameliorated DSS induced colitis on TCRαKO mice，following prolonged survival time.Although serum Ig M of mice administered DSS increased more than that of control，the cell fractions of CD 4 I D 1+I D 1 TCRVβI D 1 dim I D 1 T-cells and CD 4 I D 1+D 1 TCRVβD 1 dim I D 1 T-cells did not change with or without SEB oral administration.(Experiment2)Although TCRαKO mice have been given SEB for 9weeks，the incidence of colitis did not decrease and the cell fractions of CD4 I D1+ii D1 TCRVβI D1 dim ii D1T-cells also did not change.It was suggested that CD 4 I D 1+I D 1 TCRVβD 1 dim I D 1 T-cell may influence the onset of the colitis on TCRαKO mice.We elucidated that preventive effect of SEB on DSS induced colitis of TCRαKO mice.Therefore，it is suggested that TCRαI D1-ii D1βI D1+ii D1 cells which express the Vβregion corresponding SEB may play an important role on the onset of DSS induced colitis on TCRαKO mice.However，it was difficult to induce oral tolerance by SEB under condition of continuing local inflammation such as colitis of TCRαKO mice。

We have been elucidated that oral SEB administration prevented the onset of DSS induced colitis, and influence of clonal deletion designated by Vβ8T -cells. We evaluated the effect of oral SEB administration on TCR α KO mice. (Experiment 1) Simultaneous administration of SEB ameliorated DSS induced colitis on TCR α KO mice, following prolonged survival time. Although serum Ig M of mice administered DSS increased more than that of control, the cell fractions of CD4ィイD1+ィエD1TCRVβィイD1dimィエD1T-cells and CD4ィイD1+ィエD1TCRVβィイD1dimィエD1T-cells did not change with or without SEB oral administration. (Experiment 2) Although TCR α KO mice have been given SEB for 9 weeks, the incidence of colitis did not decrease and the cell fractions of CD4ィイD1+ィエD1TCRVβィイD1dimィエD1T-cells also did not change. It was suggested that CD4ィイD1+ィエD1TCRVβィイD1dimィエD1T-cell may influence the onset of the colitis on TCR α KO mice. We elucidated that preventive effect of SEB on DSS induced colitis of TCR α KO mice. Therefore, it is suggested that TCRαィイD1-ィエD1βィイD1+ィエD1 cells which express the Vβ region corresponding SEB may play an important role on the onset of DSS induced colitis on TCR α KO mice. However, it was difficult to induce oral tolerance by SEB under condition of continuing local inflammation such as colitis of TCR α KO mice.