Mouse Model for Asthma

1. 10% alum solution (dissolved in double distilled water) 2ml, 500ug/ml OVA (dissolved in PBS) 2ml mixed in equal parts, using NaOH to adjust to the pH6.5, and incubated at room temperature for 60 min, 750r/min, 5min, remove supernatant, dissolved in 2ml PBS. Sensitized when each mouse intraperitoneal injection of 200ul, which contains 2mg alum and 100ug OVA.
2. Inject with alum 0.2ml to abdominal cavity in day 0, 14respectively, and the control group are injected the same dose of PBS solution.
3. Atomization inhalation, on day 21, the mice into the organic glass box, 5% OVA atomizing inhalation. 30min per day, last for 7 days, within 24h of the last inhalation, detect the sensitization. Mice with irritability, shortness of breath, abdominal muscle spasm and other positive reaction as the standard of a successful model. Control group using PBS atomizing inhalation, other operations are the same.
4.Pick the eye to take blood, 4℃, 3000r, 10 minutes to extract serum, stored at -80℃. The left lung tissue was fixed in 4% poly formaldehyde solution for pathological staining; the right lung tissue was frozen in liquid nitrogen and stored at -80℃.

1. General observation:Asthma model mice after the excitation appear sneezing, nodding breathing, shortness of breath, wheezing sound, abdominal muscle contraction, irritability and other typical asthma symptoms, and eating less in the late, dull coat, bradykinesia, and weight gradually decreased.
2. Bronchial alveolar lavage fluid (BALF) collected at the 24h after first excitation (day 28). Separate the trachea, after ligation of the left main bronchus, cut the right main bronchus and insert the endotracheal tube and fixed, sterile saline lavage 3 times,1ML per time, collect BALF and 4℃,1200r/min,5 mins, the supernatant is discarded, PBS resuspends cell sedimentation,smear and classify the cells.

The left lung tissue is fixed with 4% formalin, dehydrated, embedded in paraffin, and stained with 4 m slice, HE staining. In the normal group, there was no obvious infiltration of inflammatory cells and normal structure. Asthma group showed diffuse small bronchial and vascular inflammatory cell infiltration, in which the number of eosinophils increased significantly. Airway epithelium has different degree of shedding, bronchial mucous membrane epithelial goblet cell hyperplasia, within the lumen of the visible mucous bolt and inflammatory exudative, marked thickening of bronchial smooth muscle, perivascular edema.

The content of IL-25 and IL-4 in model group is significantly higher than that in control group. The content of IL-25 and IL-4 in serum is detected by ELISA kit.

SPSS software is used for statistical analysis, measurement data to mean ± standard deviation (x ±ｓ), using t test and single factor analysis of variance for group comparison , P<0.05 indicates there was a significant difference, P<0.01 indicates there are very significant differences.