Objective      To establish a mouse model of asthma airway remodeling and investigate the changes of pathological features at different challenging time.       Methods      The mice were randomly divided into 1 control group and 5 model groups (2-

4-

6-

8- and 10-week groups) according to different challenging time. To make the airway remodeling in the allergic mice

the mice were sensitized with ovalbumin (OVA) and repeatedly challenged with OVA. Bronchoalveolar lavage fluids (BALF) were collected for counting total cells and eosinophils (EOS) at 24 h after the last challenge. The pathological changes of lung tissues were observed by HE

PAS and Masson staining.       Results      Compared with the control group

the counts of total cells and EOS were increased (P≤0.001)

and the scores of EOS infiltration and goblet cell hyperplasia were significantly higher in the 5 model groups (P0.001). However

the airway basement membrane was thicker only in the 8-week group and 10-week group (P≤0.036).       Conclusion      Airway remodeling begins in the early stage of inflammation and becomes more serious along with the challenge time. However

the pathological characteristics of remodeling do not appear at the same time. The challenge of about 8 weeks is necessary to exhibit complete pathological characteristics of airway remodeling.