哮喘支气管黏膜中类胰蛋白酶的表达增强

目的 观察含类胰蛋白酶的肥大细胞在豚鼠支气管黏膜的表达和分布特征。方法 Dunkin Hartley豚鼠随机分为哮喘组(A组)和生理盐水组(B组)。用100m/mL卵蛋白进行致敏,并于致敏后第5周行抗原特异性支气管激发试验。激发后2h取各组豚鼠支气管组织标本,免疫组化染色以抗人类胰蛋白酶(Tryptase)单克隆抗体(AAl)为一抗,过氧化物酶标记的绵羊抗鼠IgG为二抗,并用联苯二胺(Diaminobenzidine,DAB)显色。仅选择阳性染色细胞进行计数。结果 鼠抗人Trvptase单克隆抗体即可识别人支气管Tryptase又可识别豚鼠支气管Tryptase。哮喘支气管组织中Tryptase阳性细胞数明显多于正常支气管组织。相似地,支气管激发试验后的豚鼠支气管组织中的肥大细胞数要比生理盐水吸入组多出2．0倍以上。结论 抗人Tryptase单克隆抗体可以用于识别豚鼠支气管的肥大细胞。哮喘者和激发试验阳性的豚鼠支气管肺组织中的Tryptase阳性肥大细胞数明显多于正常支气管组织,表明肥大细胞在支气管哮喘发病机制中可能起重要作用。

Expression of mast cell Tryptase in bronchial mucosa of asthmatic guinea pigs

Objective To examine the expression of Tryptase-containing mast cells in the mucosa of asthmatic guinea pigs. Methods Dunkin Hartley guinea pigs were sensitized with 100 mg/mL ovalbumin and bronchial challenge was performed. At 2 hours following bronchial challenge, the bronchi of all guinea pigs tested were removed and were fixed in formalin. For immunohistochemical examination, anti-human Tryptase antibody (AA1) was employed as the first antibody, peroxidase conjugated mouse anti-human IgG was used as the second antibody and positively stained mast cells were visualized by addition of DAB. Only positive staining cells were counted. Results AA1 was found to be able to recognize the mast cells both in human and guinea pig bronchial tissues. The number of mast cells in human asthmatic bronchial tissues was more than that in normal bronchial tissues. Similarly, the number of mast cells in guinea pig bronchial tissues challenged with ovalbumin were 2.0 fold more than that challenged with normal saline. Conclusion Anti-human Tryptase antibody can be applied in guinea pig study. The increases in the numbers of mast cells in asthmatic airways indicate that mast cells are likely to be an important cell type in bronchial asthma.