The Change Of CD4～+CD25～+ Regulatory T Cells In Asthmatic Rat And The Effect Of Dexamethasone On CD4～+CD25～+T Cells

objectives: to investige the change of CD4~+CD25~+T Cells in bronchoalvelar lavage fluid (BALF ) , blood and spleen of asthmatic rat and the effect of dexamethasone on CD4~+CD25~+T Cells.Methods:50 SD rats were randomly divided into five groups with 10 rats in each group: control group(A), asthmatic group(B), dexamethasone low-dose group (dexamethasone 0.2mg/kg) (group T1),, mid-dose group (dexamethasone 1mg/kg) (group T2), high-dose group dexamethasone(2mg/kg) (group T3). The asthmatic model was established by OVA. CD4~+CD25~+T Cells in BALF blood and spleen are measure by flow cytometric analysis .Result: ①CD4~+CD25~+T cells of group B in BALF, blood and spleen are much higher than that in group A. In the BALF , the percentage of CD4~+CD25~+T cells in CD4+T cells ,group B (42.21 ±5.62%) is much higher than group A( 18.76 ±5.85%) ,P<0.01. In the blood , group B ( 10.69±2.04%)is higher than group A (6.92 ± 2.95%) ,P<0.01. In the spleen , group B (11.15 ± 1.05%) is higher than group A (7.85 + 2.13%), P<0.05.② CD4~+CD25~+T /CD4~+T of different dose dexamethasone group drop to the level of group A or lower than group A. In BALF, group T1 (10.49 ±4.03%) , group T2 (13.28 ±5.12%) , group T3 (7.51 ± 5.39% ) ,compare with group A ( 8.76 ± 5.85% ) ,the differences are...