Objective: To observe the time-course profile of airway inflammation in murine asthma model, and to analyze the dynamic profile of pro-inflammatory factor IL-5, and inflammtion-suppressing factor IL-10 in the airway.
Methods: An animal model of asthma was established by OVA sensitizing-challenging BALB/C mice. At seven points (0 h, 8 h, 24 h, 48 h, 96 h, days 7 and days 14) in the time course after challenge, bronchoalveolar lavage (BAL) was performed. Total cell counts, cell differential, eosinophil (EOS) counts and percentages were examined and levels of two Th2 cytokines, IL-5 and IL-10, were detected by ELISA.
Results: After OVA challenge, total cell counts, EOS counts and EOS percentages in BALF were increased significantly. EOS count increased at 8 h, formed a plateau from 24 h to 48 h, declined at 96 h, reduced approximately to control from days 7 to days 14. IL-5 in BALF elevated at 8 h, maitained at high level from 28 h to 96 h, decreased at days 7. The dynamic changes of IL-5 was in synchronism with that of EOS counts, a positive correlation being identified. No significant difference was found between IL-10 in BALF before and after challenge. A close correlation between EOS counts and IL-5/IL-10 ratio was demonstrated (r = 0.9, P < 0.001).
Conclusion: IL-5 and IL-10 up- and down-regulate asthmatic airway inflammation respectively, and their interaction may play an important role in inflammatory progress and resolution.