Abstract:

Objective    To explore the role of Th1/Th2 cytokines in the pathogenic process of asthma,interfering effects of thymosine-α and dexamethasone-on Th1/Th2 and their clinical values. Methods     An asthma model was set up and thymosine-α and dexamethasone were given. The rats were divided into the normal control group,the asthmic group,the thymosin group and the dexamethasone group.Levels of IL-4, IL-5 and IFN-γin bronchoalveolar lavage fluid(BALF) were detected by ELISA. Results     There was a significant increase in the numbers of EOS and lymphocytes and levels of IL-4 and IL-5, while there was a significant decrease in the level of IFN-γ in the asthmic group compared with the normal control group (P<0.05). Number of EOS and levels of IL-4 and IL-5 decreased in the thymosine dexamethasone groups compared with the asthmic group, and the difference was significant (P<0.05). The level of IFN-γ in the thymosin group increased compared with the asthmic group and the difference was significant(P<0.05). For IL-4/IFN-γ, there were notable differences between the normal group and the asthmic  group,between the asthmic group and the thymosin group,and between the asthmic group and the dexamethasone group(P<0.05). Conclusion    The Th2 dominant reaction play an important role in the pathogenesis of asthma.Thymosin-α can notably increase the level of IFN-γ. Dexamethasone can lower the levels of IL-4 and IL-5.

Key words: T-lymphocyte, helper-inducer; Thymosin; Dexamethasone; Mice