in 't Veen J C, Grootendorst D C, Bel E H, Smits H H, Van Der Keur M, Sterk P J, Hiemstra P S
Department of Pulmonology, Leiden University Medical Centre, The Netherlands.
Clin Exp Allergy. 1998 May;28(5):606-15. doi: 10.1046/j.1365-2222.1998.00279.x.
Patients with asthma show altered surface expression of the adhesion molecules CD11b and L-selectin on airway granulocytes compared with blood granulocytes.
To investigate whether this modulation is related to disease activity or due to transendothelial migration, we compared the CD11b and L-selectin expression on blood and induced sputum eosinophils and neutrophils between patients with asthma and normal subjects.
Eleven normal subjects (21-43 years), nine patients (21-34 years) with mild atopic asthma and 10 patients (20-47 years) with moderate to severe atopic asthma on regular treatment with inhaled steroids underwent sputum induction by inhalation of nebulized hypertonic saline (4.5%). CD11b and L-selectin expression on granulocytes from blood and DTT-homogenized sputum were analysed by flow cytometry. Eosinophils could be discriminated from neutrophils by using depolarized light scatter. Disease activity was assessed by baseline FEV1 and airway responsiveness to histamine (PC20).
Sputum eosinophils showed higher expression of CD11b (P<0.001) and lower expression of L-selectin (P<0.001) compared with peripheral blood eosinophils. CD11b and L-selectin expression on eosinophils from blood or sputum did not differ between the three groups. Similar results were obtained for neutrophils. The PC20 in the patients with moderate-to-severe asthma was related to CD11b expression on blood (R=-0.92, P=0.001) and sputum eosinophils (R=0.75, P=0.02).
Flow cytometry of induced sputum granulocytes from asthmatic as well as normal subjects is feasible. We conclude that the modulated expression of CD11b and L-selectin on airway granulocytes is not specific for asthmatic airway inflammation, but is probably the result of tissue migration per sé. This implies that CD11b and L-selectin expression on granulocytes in induced sputum cannot be used as marker of disease activity.
与血液中的粒细胞相比，哮喘患者气道粒细胞上粘附分子CD11b和L-选择素的表面表达发生改变。
为了研究这种调节是与疾病活动相关还是由于跨内皮迁移所致，我们比较了哮喘患者和正常受试者血液及诱导痰中嗜酸性粒细胞和中性粒细胞上CD11b和L-选择素的表达。
11名正常受试者（21 - 43岁）、9名轻度特应性哮喘患者（21 - 34岁）和10名接受吸入性类固醇常规治疗的中度至重度特应性哮喘患者（20 - 47岁）通过吸入雾化高渗盐水（4.5%）进行痰液诱导。通过流式细胞术分析血液和二硫苏糖醇（DTT）匀浆痰液中粒细胞上CD11b和L-选择素的表达。利用去极化光散射可将嗜酸性粒细胞与中性粒细胞区分开。通过基线第一秒用力呼气容积（FEV1）和气道对组胺的反应性（PC20）评估疾病活动度。
与外周血嗜酸性粒细胞相比，痰嗜酸性粒细胞显示出更高的CD11b表达（P<0.001）和更低的L-选择素表达（P<0.001）。三组之间血液或痰液中嗜酸性粒细胞上的CD11b和L-选择素表达无差异。中性粒细胞也得到了类似结果。中度至重度哮喘患者的PC20与血液中（R = -0.92，P = 0.001）和痰液嗜酸性粒细胞上的CD11b表达（R = 0.75，P = 0.02）相关。
对哮喘患者以及正常受试者诱导痰粒细胞进行流式细胞术检测是可行的。我们得出结论，气道粒细胞上CD11b和L-选择素的调节性表达并非哮喘气道炎症所特有，而可能是组织迁移本身的结果。这意味着诱导痰中粒细胞上CD11b和L-选择素的表达不能用作疾病活动度的标志物。
