Effect Of Appendectomy And Oral Tolerance On Dextran Sulfate Sodium Induced Colitis In Mice And The Involvement Of Th1/Th2 Balance And γδT Cells

Aims Analyze the effects of appendectomy and oral tolerance on dextran sulfate sodium induced colitis in mice and the involvement of Th1/Th2 balance and γδ T cells are discussed.Methods Colitis was induced with dextran sulfate sodium in mice. Observe the difference in pathology of colitis in appendectomized or sham operated mice. Changes of DTH reaction were detected after the induction of oral tolerance via single high dose or multiple low dose ingestion of ovalbumin in normal, appendectomized and sham-operated mice. Colonic extracted protein was ingested repeatedly to evaluate the changes of dextran sulfate sodium induced colitis in mice. Changes of Th1/Th2 balance in spleen and Peyer's patch and γδ T cells in intraepithelial lymphocytes and lymphocytes in lamina proper were detected after the induction of oral tolerance via multiple low dose ingestion of colonic extracted protein in appendectomized and sham-operated mice.Results (1) Appendectomy could interfere the induction of DSS induced colitis in mice with the ameliorate of disease activity index (5.56±1.99 vs 9.94±1.57, n=8 , P<0.001) and pathologic changes (30.75±4.65 vs 50.13±9.72,n=8,P<0.001) .(2) ovalbumin ingestion of single 20mg or 250μg for 5 times can both induce oral tolerance to DTH reaction after subcutaneous challenge of ovalbumin (1.25mm±0.551mm vs 2.35mm±0.423mm, n=6, P<0.01;0.53mm±0.175mm vs 2.40mm± 0.49mm ,n=6,P<0.001) .(3 ) Appendectomy may eliminate the oral tolerance induced by single 20mg ingestion of ovalbumin or postpone the oral tolerance induced by 250μg for 5 times ingestion of ovalbumin in mice.(4) Appendectomy may eliminate the oral tolerance caused by single 20mg or 250μg for 5 times ingestion of ovalbumin during DSS induced colitis in mice.(5) Ingestion of colonic extracted protein could interfere the induction of DSS induced colitis in mice with the ameliorate of disease activity index (7.83±1.47 vs 9.83±1.17,n=6, /><0.05) and pathologic changes (23.67±12.13 vs46.50±12.16,n=6,,P<0.05) .(6) Appendectomy could interfere the oral tolerance to DSS induced colitis caused by the ingestion of colonic extracted protein in mice.(7)The Thl/Th2 balance in lymphocytes of Peyers patch but not spleen may correlate with the interference of appendectomy to the oral tolerance to DSS induced colitis caused by the ingestion of colonic extracted protein in mice. Thl cells(appendectomized group: 11.5%±3.7%vsl5.2%±7.1%,n=6,P>0.05;sham operation: 10.0%±7.6%vs23.5%±7.8%,n=6,P<0.05) but not Th2 cells in Peyers patch causes the decreasement of Thl/Th2 (appendectomized group: 0.66±0.30vs0.77±0.49,n=6,P>0.05: sham operation: 0.32±0.21vsl.58±0.79,n=6,P<0.05).(8) The interference to the decreasement of the yST cells in lymphocytes of lamina proper but not IEL may correlate with the interference of appendectomy to the oral tolerance to DSS induced colitis caused by the ingestion of colonic extracted protein in mice (appendectomized group: 9.67%±4.34%vs7.32%±4.37%,n=6,P>0.05;sham operation: 8.06%tl.92%vsl7.11%±8.15%, n=6,/'<0.05) .Conclusions (1) Colitis and oral tolerance was induced individually by DSS or OVA in mice.(2) Both appendectomy and colonic extracted protein has therapeutic effects on DSS induced colitis in mice.(3) Appendectomy may interfere the oral tolerance to ingested ovalbumin in normal mice and mice with DSS induced colitis.(4) Appendectomy could interfere the oral tolerance to DSS induced colitis caused by the ingestion of colonic extracted protein in normal mice.(5) The interference of appendectomy of oral tolerance to DSS induced colitis caused by the ingestion of colonic extracted protein may correlated with the shift from Th2 to Thl in lymphocytes in Peyers patch and decline of y5 T cells in lymphocytes in lamina proper.