哮喘患者变应原诱导的晚期气道炎症中外周血嗜酸性粒细胞的功能活性。

OBJECTIVE: We aimed to investigate peripheral blood eosinophil chemotaxis, generation of spontaneous reactive oxygen species (ROS), and apoptosis in patients with allergic asthma after bronchial allergen challenge. MATERIAL AND METHODS: A total of 18 patients with allergic asthma (AA), 14 with allergic rhinitis (AR), and 10 healthy subjects (HS) underwent bronchial challenge with a specific allergen extract. Eosinophils from peripheral blood were isolated 24 h before as well as 7 and 24 h after bronchial allergen challenge. Chemotaxis, spontaneous ROS production in eosinophils, and apoptosis were analyzed by flow cytometry. Serum and induced sputum IL-5 levels were measured by ELISA; the cell count in sputum was analyzed by the May-Grünwald-Giemsa method. RESULTS: Before bronchial allergen challenge, peripheral blood eosinophil chemotaxis, spontaneous ROS production was enhanced and eosinophil apoptosis was reduced in the patients with AA as compared with AR patients and HS (P < 0.05). Meanwhile, eosinophil chemotaxis and ROS generation markedly increased in the patients with AA 7 h and 24 h after challenge compared with other groups and baseline values (P < 0.05). The percentage of apoptotic eosinophils in the patients with AA decreased at 7 h as well as 24 h after challenge when compared with other groups and the baseline values (P < 0.05). There was a significant correlation between the migrated peripheral blood eosinophil count and the sputum eosinophil count (Rs = 0.89, P < 0.0001) and the sputum IL-5 level (Rs = 0.68, P = 0.002) at 24 h after bronchial challenge only in the patients with AA. Furthermore, the percentage of peripheral blood apoptotic eosinophils significantly correlated with eosinophil count in sputum (Rs = -0.53, P = 0.02), and ROS production correlated with the serum IL-5 levels (Rs = 0.71, P = 0.01). CONCLUSION: During allergen-induced late-phase airway inflammation, peripheral blood eosinophils demonstrated further alterations of their functional activity manifested by enhanced spontaneous ROS production, increased chemotaxis, and diminished apoptosis in patients with AA.

目的：本研究旨在探讨支气管变应原激发后过敏性哮喘患者外周血嗜酸性粒细胞趋化性、自发性活性氧（ROS）生成和细胞凋亡的变化。

材料与方法：共 18 例过敏性哮喘（AA）患者、14 例过敏性鼻炎（AR）患者和 10 例健康对照（HS）接受了特异性变应原提取物的支气管激发试验。在支气管变应原激发前 24 小时以及激发后 7 小时和 24 小时，分离外周血嗜酸性粒细胞。采用流式细胞术分析趋化性、嗜酸性粒细胞自发性 ROS 生成和细胞凋亡。酶联免疫吸附试验（ELISA）测定血清和诱导痰中白细胞介素 5（IL-5）水平；用瑞氏-吉姆萨染色法分析痰细胞计数。

结果：在支气管变应原激发前，与 AR 患者和 HS 相比，AA 患者外周血嗜酸性粒细胞趋化性、自发性 ROS 生成增加，细胞凋亡减少（P<0.05）。同时，与其他组和基线值相比，AA 患者在激发后 7 小时和 24 小时时嗜酸性粒细胞趋化性和 ROS 生成显著增加（P<0.05）。与其他组和基线值相比，AA 患者在激发后 7 小时和 24 小时时，凋亡的嗜酸性粒细胞百分比降低（P<0.05）。仅在 AA 患者中，支气管激发后 24 小时时，迁移的外周血嗜酸性粒细胞计数与痰中嗜酸性粒细胞计数（Rs=0.89，P<0.0001）和痰中 IL-5 水平（Rs=0.68，P=0.002）呈显著相关。此外，外周血凋亡嗜酸性粒细胞的百分比与痰中嗜酸性粒细胞计数（Rs=-0.53，P=0.02）呈显著负相关，与 ROS 生成与血清 IL-5 水平呈正相关（Rs=0.71，P=0.01）。

结论：在变应原诱导的晚期气道炎症期间，AA 患者外周血嗜酸性粒细胞的功能活性发生了进一步改变，表现为自发性 ROS 生成增加、趋化性增强和凋亡减少。