Figure 6. Detection of Th2 cell and cytokines in BALF.

Measurements of expanded Treg cells for antigen-specificity. The mechanism of combined use of glucocorticoid and IL-2 in alleviating asthma rested on expanding antigen-nonspecific Treg cells, with a decrease in T helper 2 (Th2) cells and Th2-associated cytokines in the airway. Female BALB/c mice were immunized with OVA i.p on days 1 and 8, followed by intranasal (i.n) 2% OVA challenges on days 9–14. 5,000 IU IL-2 plus 1 μg budesonide (Bud) were administrated intratracheally on days 12–14. On day 15, mice were sacrificed and analyzed by flow cytometry and ELISA. And Treg cells were purified on day 15. (a,b) Detection of CD4+GATA3+ Th2 cell and CD4+T-bet+ Th1 composition among lymphocytes in BALF by flow cytometry. (c) Measurements of cytokines (IL-4, IL5, IL-10, IL-13 and IFN-γ) by ELISA in BALF. (d) Expanded Treg or Treg cells were purified from BALF of asthma model mice after treatment with IL-2 plus dexmethasone (Dex) for 3 days or the spleens of healthy BALB/c mice to be measured for antigen-specificity in OVA-specific proliferation assays and mixed lymphocyte reactions. *p < 0.05. (a,b,c) Data are presented as means ± SEM (n = 6 per group and data point) from 2 independent experiments. Treated group versus untreated group by Student’s t test. (c) Data are presented as means ± SEM (n = 3 per group and data point); here representative results from 1 of 2 experiments are shown. Treg cells addition group versus non-Treg cells group by Student’s t test.