Abstract:

Objective  To detect the percentage of Th17 cells in spleen and IL-17 level in bronchoalveolar lavage fluid in Dermatophagoides farinae allergic asthma mice.  Methods  Twenty BALB/c mice were randomly divided into control group（n=10） and asthma group（n=10）. Mice in control group were treated with PBS plus 2 mg Al（OH）3 and those in asthma group were sensitized with 200 μl solution［50 μg Dermatophagoides farinae crude extracts plus 2 mg Al（OH）3］ on day 0， 7 and 14. One week after the last sensitization， all mice were intranasally challenged with 50 μg Dermatophagoides farinae crude extracts daily for 7 days. Twenty-four hours after the last challenge， mice were sacrificed. The sera， bronchoalveolar lavage fluid（BALF） and spleens were collected. The serum levels of IgE and IgG1， and IL-17 level in BALF were determined by ELISA. The percentage of Th17 cells in spleen was tested by flow cytometry.  Results  The serum levels of IgG1 and IgE in asthma group were（0.10±0.01） pg/ml and （1.15±0.10） pg/ml， respectively， which were higher than that of the control［（0.06±0.01） pg/ml and （0.04±0.01） pg/ml］（P<0.05）. IL-17 level in asthma group（85.13±2.36） pg/ml was higher than that of the control[（48.27±4.14） pg/ml]（P<0.01）. The percentage of Th17 cells in asthma group[（5.19±0.68）%] was also higher than that of the control[（0.95±0.19）%]（P<0.01）. Meanwhile， the percentage of Th17 cells in spleen was positively correlated with IL-17 level in BALF（r=0.851， P<0.01）.  Conclusion  Compared with healthy mice， both the percentage of Th17 cells in spleen and IL-17 level in BALF have increased significantly in Dermatophagoides farinae allergic asthma mice.

Key words: Asthma, Dermatophagoides farinae, Th17, IL-17, Mouse