美洲大蠊粗浸液致SD大鼠过敏性哮喘模型建立

Establishment of an animal model of allergic asthma based on SD rat sensitized by American cockroach crude extract

目的探讨美洲大蠊粗浸液是否致SD大鼠哮喘。方法 30只雌性SD大鼠随机分为3组(每组10只),即对照(PBS)组,卵清蛋白(OVA)组和美洲大蠊粗浸液组。于第0、7、14及21天用OVA大鼠皮下注射致敏,而从第22天到第28天用OVA液对大鼠进行雾化吸入激发,每天1次,每次30 min;对照组、美洲大蠊粗浸液组分别相应用PBS、美洲大蠊粗浸液进行致敏和激发试验。ELISA检测大鼠血清中总IgE及IL-4水平,HE染色观察大鼠肺部组织的改变,免疫组化检测肺嗜酸粒细胞(eosinophils,EOS)B淋巴细胞瘤/白血病-2(B-cell lymphoma/leukemia-2,Bcl-2)的表达。结果与对照组相比,OVA组和美洲大蠊粗浸液组的血清中总IgE及IL-4含量均显著升高(P<0.01)。与对照组相比,OVA组和美洲大蠊粗浸液组HE染色的肺组织气道壁黏膜、黏膜下、肺间质和小血管周围可见大量的炎性细胞浸润;肺间质及肺泡腔内可见嗜酸性粒细胞;黏膜明显充血水肿;气道黏膜层及黏膜下层明显增厚;杯状细胞增生,上皮细胞坏死、脱落,气道内有黏液栓及脱落的黏膜上皮,支气管黏膜皱襞增多卷曲,官腔狭窄。与对照组相比,OVA组和美洲大蠊粗浸液组的肺组织Bcl-2蛋白表达均为显著升高(P<0.01)。结论用美洲大蠊粗浸液成功建立了SD大鼠哮喘动物模型。

To develop a rat model of allergic asthma by using Periplaneta americana crude extract（PAE） as clinical relevant allergen, total of 30 female SD rats were randomly divided into negative control group（group A, n=10）, positive control group（group B, n=10） and PAE group（group C, n=10）, which were sensitized and challenged with PBS, OVA, and PAE, respectively. The lungs of the rat were stained with haematoxylin and eosin（HE staining）to detect pathological change; the levels of Bcl-2 protein in lungs were detected by immunohistochemistry. The levels of IL-4 and total IgE（T-IgE） in serum were detected by enzyme-linked immunosorbent assay（ELISA）.Compared with group A, rat in groups B and C demonstrated significant abnormal reactive inflammation in airway,higher levels of IL-4 and T-IgE in serum（P 0.01）, and higher level of Bcl-2 protein in lung tissues（P 0.01）. The lung tissues of groups B and C appeared narrowing of alveolar space and interstitial infiltration of inflammatory and mononuclear cells, neutrophils, eosinophils, and lymphocytes. A numbers of infiltrated eosinophils in the peribronchial areas were observed in the PAE group and OVA group. In conclusion, PAE could be used for establishment of an animal model of allergic asthma.