Reduced eosinophil apoptosis in induced sputum correlates with asthma severity.

This study was carried out to investigate the relationship between induced sputum eosinophil apoptosis and clinical severity score, airway obstruction and symptom scores in patients with chronic stable asthma. Altogether, 41 chronic stable asthmatic subjects of varying severity defined by Aas score and 17 control subjects underwent spirometry, symptom questionnaire and successful sputum induction. Sputum was processed and cytospins prepared for light microscopy to determine normal and apoptotic eosinophils. Mild asthmatic subjects had a significantly lower percentage sputum eosinophils and a significantly higher eosinophil apoptotic ratio (AR) than moderate or chronic severe asthmatics. Severe asthmatic subjects had a significantly greater age, duration of asthma and sputum eosinophil count x mL(-1) than mild asthmatic subjects. Asthmatic subjects' symptom scores, severity scores and age inversely correlated with AR and the percentage of sputum eosinophils. Baseline forced expiratory volume in one second inversely correlated with percentage sputum eosinophils and positively correlated with AR. The study demonstrates a relationship between reduced sputum eosinophil apoptosis and increased clinical severity of chronic stable asthma, providing additional evidence that eosinophil apoptosis may be important in the resolution of eosinophilic airway inflammation in asthma.     

Kinetics of allergen-induced airway eosinophilic cytokine production and airway inflammation.

Airway eosinophilia is the hallmark of asthma exacerbation. Coordination of cytokines such as interleukin (IL)-5, eotaxin and regulated on activation, normal T-cell expressed and secreted (RANTES) seem to be necessary for eosinophil extravasation including adhesion, chemotaxis, and activation. The purpose of this study was to characterize both the kinetics of allergen-induced inflammatory cell recruitment to the airways and cytokines selective for eosinophil chemotaxis, activation, or resolution. Eight atopic asthmatic individuals demonstrating a dual response to inhaled allergen completed a diluent-controlled crossover study. The subjects showed significant allergen-induced early and late airway asthmatic responses (p < 0.001), and an increase in the number of sputum eosinophils and metachromatic cells (p < 0.05). The number of eosinophils immunopositive for IL-5, eotaxin, and RANTES increased 7 h after allergen inhalation (p < 0.05), coincident with the peak number of activated eosinophils. Sputum cells immunopositive for IL-10 decreased significantly following allergen challenge (p = 0. 04), and correlated negatively with sputum eosinophils (r = -0.34, p = 0.02). This study shows that allergen-induced increases in sputum eosinophils are associated with the presence of cytokines specific for the activation and chemotaxis of eosinophils, and suggests that cooperation of eosinophilic cytokines may be important for the accumulation and regulation of activated eosinophils at the site of allergic inflammation.     

Apoptotic eosinophils in sputum from asthmatic patients correlate negatively with levels of IL-5 and eotaxin

BACKGROUND: Eosinophilic inflammation of the airways is a key characteristic of asthma. A defect in eosinophil apoptosis might contribute to the chronic tissue eosinophilia associated with asthma. OBJECTIVE: Our purpose was to examine whether the occurrence of apoptotic eosinophils in induced sputum from asthmatic patients correlate with interleukin (IL)-5 and eotaxin. METHODS: Thirty stable and 30 exacerbated asthmatic patients were recruited. Twenty healthy subjects were enrolled as a control group. Induced sputum was obtained from asthmatic patients and from control subjects. The number of apoptotic eosinophils in sputum was assessed by flow cytometry. In sputum supernatant, eosinophil cationic protein (ECP) was measured by sensitive radioimmunoassay, and IL-5 and eotaxin by sandwich enzyme linked immunosorbant assay. RESULTS: Levels of eosinophils, apoptotic eosinophils, IL-5, ECP and eotaxin from asthmatic patients were higher than those from healthy subjects. Thirty exacerbated asthmatics showed higher proportions of eosinophils (median 29.3%, range 13.4%-40.9%), more detectable levels of IL-5 (50.44, 32.99-67.01 pg/ml) and eotaxin (644.6, 197.4-937.7 pg/ml) in their sputum than the patients with stable asthma (P<0.05). There were significant inverse correlations between the levels of sputum IL-5 and the proportion of sputum eosinophil apoptosis in patients with exacerbated and stable asthma (r=-0.85 and -0.79, P<0.01 and P<0.05, respectively). Also inverse correlations were found between the levels of eotaxin and the proportion of sputum eosinophil apoptosis in exacerbated (r=-0.85, P<0.01), or stable asthma (r=-0.69, P<0.05). Additional positive correlations between the levels of sputum IL-5 and eotaxin in either exacerbatated (r=0.93, P<0.01) or stable asthma (r=0.82, P<0.05) were observed. CONCLUSIONS: Apoptosis of eosinophils might be suppressed by proinflammatory cytokines and chemokines such as IL-5 and eotaxin leading to their accumulation in the lung. Stimulation of eosinophils in airway with IL-5 and eotaxin may play a crucial role in allergic inflammation.     

Increased expression of the chemoattractant cytokines eotaxin, monocyte chemotactic protein-4, and interleukin-16 in induced sputum in asthmatic patients

BACKGROUND: Induced sputum from asthmatic patients has been recently used to assess inflammatory cells. We have previously reported an increased expression of Th-2-type cytokines in induced sputum of asthmatic patients. C-C chemokines, particularly eotaxin and monocyte chemotactic protein (MCP)-4, are associated with eosinophilic infiltration. Interleukin (IL)-16 is associated with chemotactic activity for CD4+ cells. Chemokine expression in BAL and bronchial biopsy specimens has been demonstrated in asthmatic airways, but not in induced sputum. METHODS: We examined whether eotaxin, MCP-4, and IL-16 expression could be detected in induced sputum of asthmatic patients (n = 10), and whether the expression was increased compared to normal control subjects (n = 9). Eotaxin, MCP-4, and IL-16 immunoreactivity were determined by immunocytochemistry. In addition, inflammatory cells were investigated using markers for T cells (CD3), eosinophils (major basic protein [MBP]), macrophages (CD68), neutrophils (elastase), and epithelial cells (cytokeratin). RESULTS: Our results showed that there was a significant difference in the percentages of MBP-positive and epithelial cells between asthmatic patients and normal control subjects (p < 0.05). However, there was no difference between these two groups in the percentage of CD3-, elastase-, and CD68-positive cells. Immunoreactivity for eotaxin, MCP-4, and IL-16 was expressed in the induced sputum of all asthmatic patients, and expression of these chemotactic cytokines was significantly greater than in control subjects (p < 0.001, p < 0.005, and p < 0.001, respectively). CONCLUSIONS: This study showed that induced sputum could be used to detect chemokines in patients with bronchial asthma, and that the upregulation of chemotactic cytokines in the airways can be seen using noninvasive techniques.     

支气管哮喘患者诱导痰中基质细胞衍生因子的表达及其作用

目的 测定支气管哮喘(简称哮喘)患者在糖皮质激素(简称激素)治疗前后诱导痰中基质细胞衍生因子-1(SDF-1)和白细胞介素(IL)-17的水平,探讨SDF-1在哮喘发病机制中的作用.方法 收集2009年6月至2010年9月郑州大学第一附属医院门诊及住院的慢性持续期的哮喘患者99例(按病情严重程度分为轻、中、重度组)及健康体检者30名,哮喘患者在回答哮喘控制问卷(ACQ)后,两组研究对象分别进行肺功能检测和诱导痰检查,记录FEV1占预计值%,行诱导痰炎症细胞分类计数,酶联免疫吸附试验(ELISA)法检测诱导痰中SDF-1和IL-17水平;所有哮喘患者均参照支气管哮喘指南给予规范的吸入激素为主的治疗,4周后测定诱导痰中SDF-1、IL-17的水平及炎症细胞比率.结果 轻、中、重度持续组的ACQ评分及FEV1占预计值%差异均有统计学意义(F值分别为79.271和457.448,均P<0.01).治疗前哮喘组诱导痰嗜酸粒细胞比率、IL-17水平及SDF-1水平均高于健康对照组(均P<0.01);重度哮喘患者诱导痰中两种炎症细胞比率及SDF-1和IL-17水平均高于轻度哮喘患者(均P<0.05).哮喘患者FEV1占预计值%与诱导痰中嗜酸粒细胞、中性粒细胞比率均呈负相关(r值分别为-0.316和-0.409,均P<0.05);诱导痰中SDF-1与嗜酸粒细胞比率及中性粒细胞比率呈正相关(r值分别为0.875和0.716,均P<0.01);诱导痰中IL-17与嗜酸粒细胞及中性粒细胞比率呈正相关(r值分别为0.878和0.846,均P<0.01);诱导痰中SDF-1与IL-17水平呈正相关(r=0.872,P<0.01).治疗后哮喘患者诱导痰中两种炎症细胞比率及SDF-1和IL-17水平均低于治疗前患者(均P<0.01);治疗后未控制组哮喘患者诱导痰中性粒细胞比率、SDF-1水平和IL-17水平明显高于完全控制组(均P<0.05).结论 SDF-1和IL-17通过募集炎症细胞,特别是中性粒细胞参与了哮喘气道炎症的发生,SDF-1可作为哮喘患者临床病情判定和疗效观察的参考指标.

Abstract：

Objective To evaluate concentrations of stromal cell-derived factor 1 (SDF-1) and IL-17 in induced sputum supernatants from asthmatic patients before and after treatment with glucocorticosteroids. Methods Induced sputum was collected from 30 healthy controls and 99 patients with chronic persistent asthma from 2009-2010. Sputum samples were obtained before and after 4 week treatment with inhaled glucocorticosteroids. The sputum concentrations of SDF-1 and IL-17 were measured by ELISA. Results The FEV1% and the asthma control score of patients with severe asthma were decreased as compared with patients with moderate persistent and mild persistent asthma (F=457.448 and 79.271, all P<0.01). The concentrations of SDF-1 ,IL-17 and the percentage of eosinophils were increased in asthma group compared with control subjects (all P<0.01),but the percentage of sputum neutrophils was lower than that in the healthy controls(P<0.01). The percentage of sputum neutrophils and eosinophils and the level of SDF-1 and IL-17 in patients with severe persistent asthma were significantly higher than those in patients with mild persistent asthma (all P<0.05). The percentage of sputum neutrophils and eosinophils were negatively correlated with FEV1%(r=-0.409 and -0.316,all P<0.05). The levels of IL-17 and SDF-1 were positively correlated with the percentage of sputum neutrophils and eosinophils (all P<0.01). The levels of IL-17 were positively correlated with the levels of SDF-1(r=0.872, P<0.01).After glucocorticosteroid therapy, the percentage of eosinophils and neutrophils, the levels of IL-17 and SDF-1 decreased significantly in all patients(all P<0.01), while the percentage of sputum neutrophils and the levels of IL-17and SDF-1 in uncontrolled patients increased significantly compared with the controlled and partly controlled groups(all P<0.05). Conclusions SDF-1 and IL-17 may contribute to airway inflammation in asthma by chemotactic activity towards neutrophils. The concentration of SDF-1 may be used to evaluate the inflammation and the therapeutic effects.     

Eotaxin level in induced sputum is increased in patients with bronchial asthma and in smokers

BACKGROUND: Airway eosinophilia is one of the hallmarks of asthma. Eotaxin may play an important role in eosinophil recruitment. OBJECTIVES: To examine the relationship between eotaxin levels in the sputum and eosinophilic inflammation. METHODS: The sputum was obtained from 11 non-smokers, 14 smokers and 13 asthmatic patients using a sputum induction method. Eotaxin and interleukin (IL)-5 levels in the sputum were determined by ELISA and immunocytochemical analysis. RESULTS: Asthmatic patients had eosinophilia and smokers showed neutrophilia in their sputum. The eotaxin level in the sputum was significantly higher in smokers (median 412.5, range 91.1-872.2 pg/ml) and asthmatic patients (351.0, 185.0-928.0 pg/ml) compared with non-smokers (123.2, 0-369.0 pg/ml; both p < 0.05). IL-5 was detected in the sputum of 1 non-smoker, none of the smokers and 4 asthmatic patients. The percentage of eotaxin-positive cells was higher in smokers and asthmatic patients than in non-smokers, but the percentage of IL-5-positive cells was significantly higher only in asthmatic patients (p < 0.05). CONCLUSIONS: These findings suggest that the elevated eotaxin level in the sputum does not always accompany the increase in eosinophils, and cooperation with another cytokine such as IL-5 may be required for the recruitment of eosinophils.     

Immunohistochemically stained activated eosinophils in sputum in patients with asthma

BACKGROUND: Eosinophils play an important role in asthmatic airway inflammation. Monoclonal antibody EG2 has been considered to identify activated eosinophils. OBJECTIVE: The present study was aimed to investigate whether immunohistochemically stained EG2+ eosinophils in sputum reflect the severity of asthma. METHODS: Sputum was obtained in 23 asthmatic patients, of whom 13 patients were examined before and after antiasthma treatment including steroid preparations. We used immunohistochemical staining to detect EG2+ (activation marker) eosinophils and fluoroimmunoassay to detect eosinophil cationic protein (ECP). RESULTS: Moderate to severe asthmatics had a significantly higher proportion of eosinophils and EG2+ eosinophils and higher levels of ECP compared to mild asthmatics (40.9 +/- 5.8 vs. 6.4 +/- 1.2%, 35.5 +/- 5.6 vs. 2.7 +/- 1.0%, 1.470.2 +/- 251.5 vs. 210.6 +/- 52.0 microgram/l, respectively; p < 0.01). Significant increases in proportions of eosinophils, EG2+ eosinophils and ECP in the sputum from patients with exacerbated asthma were evident. The proportions of eosinophils, EG2+ eosinophils, and the levels of ECP were reduced following treatment with antiasthmatic drugs. FEV(1) and FEV(1)/FVC were significantly correlated with EG2+ eosinophils. CONCLUSION: These findings demonstrate that EG2+ eosinophils in sputum are closely related to the clinical status in patients with asthma.     

Smoking Affects Eotaxin Levels in Asthma Patients

Background. Chronic airway inflammation is most important pathological finding in asthma. Cigarette smoking may modify type of inflammation as well as may influence disease severity and response to the treatment. Objective. Thus the aim of this study was to investigate whether cigarette smoking may have an influence on the levels of eotaxin-1, eotaxin-2, eotaxin-3 and IL-5 in patients with stable mild/moderate asthma. Methods. 45 steroid naive asthmatics (mean age: 55.2 ± 2.2 yrs) and 23 “healthy” smokers and non-smokers control subjects (mean age: 54.4 ± 9.7 yrs) were investigated. Asthmatics were divided into two subgroups according to their smoking histories: asthmatic smokers (n = 19) who currently smoke and have a history of > 10 pack-years and asthmatic never-smokers (n = 26). BAL and induced sputum were performed. Cytospins of induced sputum and BAL were stained with May-Grünwald-Giemsa for differential cell counts. Eotaxin-1, eotaxin-2, eotaxin-3 and IL-5 concentrations in serum, sputum and BAL supernatant was measured using a commercial ELISA kit. Results. In sputum supernatant from asthma smokers was significantly higher concentration of eotaxin-1 than in non-smokers asthmatics (203.4 ± 10.0 vs. 140.2 ± 9.5 respectively, p < 0.05). In non-smokers asthma patients levels of BAL eotaxin-1 strongly related to percent and absolute numbers of BAL eosinophils and neutrophils (Rs = 0.737 and Rs = 0.514 respectively, p < 0.05). The number and percent of sputum neutrophils and eosinophils, obtained from smokers asthmatics, significantly correlated with eotaxin-2 concentration in sputum supernatant (Rs = 0.58 and Rs = 0.75 respectively, p < 0.05). IL-5 levels in the serum and sputum from asthmatic never-smokers were significantly higher than they were from asthmatic smokers and “healthy” smokers. Asthmatic never-smokers showed a significantly higher amount of IL-5 in serum and sputum than the asthmatic smokers showed. Conclusions. This study showed the elevated levels of sputum eotaxin-1 as well as serum, sputum and BAL eotaxin-2 in asthmatic smokers without a significant increase of eosinophils compared to asthmatic never-smokers. The eotaxin concentrations were related not only with number of eosinophils but also with the number of neutrophils in all the studied tissue compartments. The data herein permits a suggestion that smoking may influence change in asthmatic airway inflammation by stimulating the production of eotaxins.     

诱导痰嗜酸粒细胞与慢性持续期支气管哮喘病情严重程度的关系

目的 观察初诊不同病情严重程度慢性持续期支气管哮喘(简称哮喘)患者的诱导痰嗜酸粒细胞(eosinophil,EOS)比例变化,探讨二者之间的关系,并分析诱导痰EOS比例与肺功能的相关性.方法 收集专科门诊就诊的63例初诊慢性持续期哮喘患者,根据症状分为轻度持续、中度持续、重度持续3组,分别予诱导痰和肺功能检查.观察不同病情严重程度的患者气道炎症状况.对所得数据用SPSS 15.0软件分析,各组间总体分析采用Kruskal-Wallis法,两组间分析采用Mann-Whitney U test法.结果 ①慢性持续期患者诱导痰EOS比例随病情严重程度增加呈增高趋势,重度持续患者诱导痰EOS比例显著高于轻度持续患者(41.8%vs 17.8%,P=0.033),但轻度持续与中度持续、中度持续与重度持续患者之间比较诱导痰EOS比例差异无统计学意义(P>0.05);②诱导痰EOS比例与第1秒用力呼气容积差异无统计学意义(r=-0.111,P>0.05),与第1秒用力呼气容积/用力肺活量(%)差异无统计学意义(r=-0.154,P>0.05).结论 慢性持续期哮喘患者病情严重程度与诱导痰EOS比例有关,但症状不能完全反映气道炎症程度.评价哮喘患者的严重程度时应结合临床症状和气道炎症程度综合考虑.     

诱导痰炎性标志物检测在判定哮喘严重程度和鉴别诊断中的应用

目的探讨哮喘患者诱导痰中嗜酸性粒细胞(Eos)和嗜酸细胞阳离子蛋白(ECP)与其哮喘严重程度的关系及鉴别诊断价值。方法选择武汉大学人民医院2002-07~2004-06的门诊哮喘患者59例,检测其肺功能并分别采用瑞氏染色及荧光免疫法检测高渗盐水诱导痰中Eos数量和ECP质量浓度。选择同期20例慢性阻塞性肺疾病患者和10名健康人作为对照。结果哮喘患者诱导痰中Eos数量与患者第1秒用力呼气容积/用力肺活量(FEV1%)呈显著负相关(r=-0·65,P<0·01);ECP质量浓度与患者FEV1%呈显著负相关(r=-0·59,P<0·01)。随病情加重哮喘患者诱导痰中Eos数量和ECP质量浓度逐渐升高,且轻度、中度和重度患者之间比较差异有统计学意义(P<0·05)。哮喘患者诱导痰中Eos数量和ECP质量浓度显著高于慢性阻塞性肺疾病组和健康组(P<0·01)。结论诱导痰中Eos和ECP质量浓度可了解哮喘的严重程度,并有助于与慢性阻塞性肺疾病的鉴别。     

The effect of pranlukast on allergen-induced bone marrow eosinophilopoiesis in subjects with asthma

We investigated the mechanisms by which leukotriene receptor antagonists decrease airway eosinophil number. In a randomized, double-blind crossover study, we examined the effects of 2 weeks of treatment with pranlukast 300 mg twice a day or placebo on allergen-induced changes in airway eosinophil number and bone marrow eosinophil progenitors in 15 subjects with mild asthma. Pranlukast treatment for 2 weeks decreased mean sputum eosinophil count from 0.15 x 10(6)/g (5.3% of cells) before treatment to 0.02 x 10(6)/g (0.7% of cells) after treatment (p < 0.05), whereas placebo did not. Pranlukast also decreased the eosinophil count (5.6% at 7 hours and 7.5% at 24 hours) (p < 0.05) after allergen inhalation compared with placebo (13.8% at 7 hours and 15.3% at 24 hours). There was a similar trend for sputum cells immunostaining for EG2, eotaxin, interleukin-5, and regulated upon activation, normal T cell expressed and secreted. Pranlukast also significantly attenuated the allergen-induced increase in the number of bone marrow eosinophil/basophil cfu (mean 0.3) at 24 hours compared with placebo (mean 6.2). The proportion of CD34(+) cells expressing the eotaxin receptor CC chemokine receptor 3, 24 hours after allergen inhalation, was also reduced by pranlukast. We conclude that, the cysteinyl leukotriene receptor antagonist, pranlukast, attenuates allergen-induced increase in airway eosinophils by decreasing bone marrow eosinophilopoiesis and airway chemotactic and eosinophilopoietic cytokines.     

NO in exhaled air is correlated with markers of eosinophilic airway inflammation in corticosteroid-dependent childhood asthma.

The relationship between nitric oxide in exhaled air, levels of sputum eosinophils, sputum eosinophil cationic protein (ECP) and urinary eosinophil protein X (EPX) excretion has not yet been investigated in corticosteroid-dependent childhood asthma. Therefore, taking 25 children with stable asthma (mean age 11.2 yrs) treated with inhaled corticosteroids and nine nonatopic healthy control children (mean age 12.8 yrs) the level of exhaled NO was measured by means of a chemiluminescence analyser before and after sputum induction. This was conducted as a slow vital capacity manoeuvre under standardized conditions with a target flow of 70 mL x s(-1) against a resistance of 100 cm H2O x L(-1) x s. Sputum induction was performed by inhalation of hypertonic saline (3, 4, and 5%) in a standardized manner and a single sample of urine was collected. Exhaled NO (p = 0.01), absolute eosinophil cell counts in sputum (p = 0.02), sputum ECP (p = 0.09) and urinary EPX excretion (p = 0.02) were higher in asthmatics compared to control children. Exhaled NO was positively correlated with sputum ECP (r(s) = 0.59, p = 0.002), urinary EPX (r(s) = 0.42, p = 0.03), and sputum eosinophils (r(s) = 0.30, p = 0.15) in the asthmatic children. These correlations appeared to be pronounced after sputum induction, where NO values had decreased (p = 0.01). None of the correlations were observed in the group of nonatopic control subjects. Additionally there were significant correlations between sputum ECP and sputum eosinophils (r(s) = 0.69, p<0.001) as well as between sputum ECP and urinary EPX excretion (r(s) = 0.58, p = 0.003) in the asthmatics. Exhaled NO provides information about the degree of eosinophilic airway inflammation and thus appears to be a useful and easy-to-perform inflammatory marker in corticosteroid-dependent asthma.     

Eosinophilic inflammation in sputum of poorly controlled asthmatics.

Despite full effective treatment, asthmatic patients often present with poorly controlled asthma. Airway eosinophilia is associated with asthma, but its relationship with asthma control is still undetermined. To investigate the relationship between airway eosinophilia and asthma control, cellular and biochemical markers of airway inflammation were measured in 19 subjects with poorly controlled asthma, 16 subjects with asthma under control and eight normal volunteers. The severity of asthma was mild-to-moderate persistent in 23 patients (14 poorly controlled) and severe prednisone-dependent in 12 subjects (five poorly controlled). Induced sputum was analysed for total and differential cell counts, leukotriene E4 (LTE4), eosinophil cationic protein (ECP), regulated on activation, normal T-cell expressed and secreted (RANTES), and interleukin (IL)-8. Sputum eosinophils, LTE4, ECP and RANTES levels (but not IL-8) were significantly higher in patients with poorly controlled asthma as compared to patients with controlled asthma. By contrast, sputum cells and sputum inflammatory markers were not different among groups of patients with different severity of asthma. These results suggest that sputum eosinophilia is associated with poorly controlled asthma rather than with the severity of asthma.     

支气管哮喘气道炎症可能机制的探讨

目的 探讨支气管哮喘(简称哮喘)患者气道炎症特征及其可能机制,并进一步观察吸入糖皮质激素治疗对气道炎性细胞分类计数、炎症介质等的影响.方法 分别选择轻度(轻度组)、中度(中度组)和重度(重度组)持续哮喘患者15例、14例和19例,正常对照组15名,分别行哮喘症状控制评分、肺功能测定、诱导痰炎性细胞分类计数、调节激活正常T细胞表达和分泌细胞因子(RANTES)、嗜酸粒细胞阳离子蛋白(ECP)、白介素8(IL-8)及髓过氧化物酶(MPO)浓度检测,然后规范吸人糖皮质激素治疗4周,随访复查上述指标.结果 诱导痰NEU%、IL-8及MPO重度组明显升高,分别为(62.40±22.05)%、594.53±85.11、39.25±10.67与轻度组[(47.23±15.12)%、183.63±120.98、12.47±4.15]、中度组[(46.13±19.23)%、352.76±71.72、22.93±7.35]、正常对照组[(31.44±13.31)%、103.26±36.33、10.22±4.13]比较差异均有统计学意义(P＜0.01);RANTES、嗜酸粒细胞百分比(EOS%)和ECP浓度在各哮喘组间比较差异无统计学意义(P＞0.05).EOS%与RANTES、ECP水平呈正相关(r=0.557,P＜0.05;r=0.852,P＜0.01);NEU%与IL-8、MPO水平呈正相关(r=0.732,P＜0.05;r=0.806,P＜0.05);经糖皮质激素治疗后,对轻、中、重度哮喘患者合并进行分析表明,治疗后症状评分由(9.8±5.4)分下降至(4.0±3.5)分和肺功能指标第一秒用力呼气容积占预计值百分比由(62.2±23.3)%升高至(75.9±17.5)%显著改善,差异有统计学意义(P＜0.01).在接受糖皮质激素治疗后,RANTES、EOS%和ECP水平均显著降低.另外MPO水平也显著降低(P＜0.01);但治疗后在重度组仍显著高于轻、中度组(P＜0.01).但IL-8、NEU%治疗后无明显降低(P＞0.05),而且治疗后IL-8、NEU%在重度组仍显著高于轻、中度组(P＜0.01).结论 中性粒细胞增多是重度哮喘的气道炎症特征之一,EOS与病情严重程度无关.EOS哮喘的发生可能与RANTES的趋化、EOS的活化、ECP的释放有关,激素可以抑制EOS气道炎症.而中性粒细胞哮喘的发生可能与IL-8的趋化、NEU的活化、MPO的释放有关.     

The Value of Sputum 8-Isoprostane in Detecting Oxidative Stress in Mild Asthma

Background. Exhaled nitric oxide and induced sputum eosinophils are well established as direct markers of inflammation/oxidative stress in asthma. Recently, it has been proposed that sputum 8-isoprostane concentrations may present a reliable index for measuring oxidative stress in asthmatic patients. We assessed the value of sputum 8-isoprostane in mild asthma in children and adolescents. Methods. Patients with newly diagnosed asthma (children, n = 23; adults, n = 14) and age-matched healthy controls (children, n = 13; adults, n = 15) were studied. Lung function was measured by spirometry, sputum was induced by hypertonic saline, and fractional exhaled nitric oxide (FeNO) was measured with standard methods. Cell differential counts were obtained from sputum slides and the concentration of 8-isoprostane was measured with an enzyme immunoassay from sputum supernatants. Results. High-quality sputum specimens could be obtained from 10 children and 10 adults, and the sputum analyses were conducted only for the representative specimens. Asthmatics had increased FeNO (children 35.5 vs. 11.9 ppb; adults 81.1 vs. 16.6 ppb; p < 0.001) and sputum eosinophils (children 2.4% vs. 1.4%; adults 10.4% vs. 0.2%; p = 0.005) compared to healthy controls. There was a significant correlation between FeNO and eosinophils (R = 0.65; p < 0.0001). Sputum 8-isoprostane was not elevated in asthmatics compared to healthy subjects (children 81.1 vs. 89.9 and adults 76.9 vs. 73.4 pg/mL) and did not correlate with lung function or other measurements of airway inflammation. However, increased 8-isoprostane levels were detected in patients with chronic obstructive pulmonary disease (n = 11, 184.7 pg/mL, used as controls for assays). Conclusions. In agreement with earlier studies, FeNo is sensitive in detecting oxidative/nitrosative stress in asthmatic airways. However, our results suggest that 8-isoprostane may not be sensitive in reflecting oxidant burden in mild asthma.     

Relationship between the perception of dyspnoea and airway inflammatory markers

Poor dyspnoea perception in asthmatic patients seems to be associated with increased risk of asthma exacerbation. We have studied the relationship between basel ne dyspnoea perception and inflammatory markers in sputum in eight patients with mild asthma and in 13 patients with moderate to severe asthma.The perception of dyspnoea was scored on the Borg scale. Eosinophilic cationic protein (ECP) was measured by fluoroimmunoassay and by an interleukin (IL)-5 sandwich ELISA. The baseline Borg score was significantly higher in patients with severe asthma than in patients with mild to moderate asthma (4.1 +/- 0.29 vs. 2.28 +/- 0.28, P<0.05).The proportion of eosinophil and ECP levels in the sputum were significantly higher in patients with moderate to severe asthma. IL-5 in sputum was significantly increased in moderate to severe asthmatic patients compared to mild asthmatic patients. A significant relationship was found between the baseline perception score and FEV1/FVC (r = -0.53, P<0.01), sputum eosinophils (r = 0.70, P<0.01) and sputum ECP (r = 0.62, P<0.01).These findings suggest that the baseline perception score is related to inflammatory markers in sputum, and that the perception of dyspnoea as well as airway inflammatory markers may be considered to evaluate asthma severity.     

Analysis of sputum cell counts during spontaneous moderate exacerbations of asthma in comparison to the stable phase.

BACKGROUND: Acute airway inflammation is considered to characterize asthma exacerbations, but its specific cellular pattern has not yet been completely evaluated. AIM: To evaluate the prevalence of sputum eosinophilia during acute asthma exacerbations of moderate severity, compared with a stable phase of the disease, and to assess the concordance between changes in pulmonary function and sputum eosinophilia in the period between exacerbation and post exacerbation. METHODS: We compared sputum and blood inflammatory cell counts in 29 asthmatic subjects during a spontaneous moderate exacerbation of asthma (visit 1) with sputum and blood cell counts measured 4 weeks after the resolution of asthma exacerbation (visit 2). At visit 1, all subjects required an appropriate 1 week treatment with oral corticosteroids. RESULTS: At visit 1, all subjects were able to collect spontaneous sputum, whereas at visit 2 sputum was induced by inhalation of hypertonic saline (NaCl 3, 4, and 5%, 10 minutes each) with beta2-agonist pretreatment. Asthma exacerbation was accompanied by a significant increase in sputum eosinophil percentages compared with levels after exacerbation [25% (1-78) versus 4% (0-23), p<0.05). Only four subjects showed low sputum eosinophil percentages during exacerbation, and these showed no differences in main clinical findings with respect to subjects with sputum eosinophilia. At visit 2, the stability of asthma was assessed on the basis of PEF, FEV1, symptoms, and use of rescue beta2-agonist. Asthma was defined as stable in 21 out of 29 subjects. Sputum eosinophil percentages fell significantly between visit 1 and visit 2 in both stable and unstable patients, but at visit 2 sputum eosinophil percentages were still high in subjects with unstable asthma. In patients who proved to be stable at visit 2, there was a significant correlation between the changes recorded in sputum eosinophil percentages and in FEV1 between the two visits (rho: 0.723, p<0.001). CONCLUSION: Sputum cosinophil but not neutrophil percentages increase in most asthmatic subjects during moderate exacerbation of asthma. Changes in the degree of airway eosinophilic inflammation are related to changes in the severity of airway obstruction during asthma exacerbation.     

Evidence of mast-cell activation in a subset of patients with eosinophilic chronic obstructive pulmonary disease.

Although asthma has been viewed mainly as an eosinophilic disease, and chronic obstructive pulmonary disease (COPD) as a neutrophilic disease, recent studies have shown increased neutrophil counts in severe asthma and sputum eosinophilia in some COPD patients. In an attempt to further characterise these two syndromes according to pathology, the current authors have conducted a study of induced sputum in 15 subjects with COPD, 17 asthmatics, and 17 nonatopic healthy individuals. Sputum was analysed for cytology and levels of eosinophil cationic protein (ECP), albumin, tryptase and soluble intercellular adhesion molecule-1. The COPD subjects differed from the asthmatics as they had higher sputum neutrophil and lower columnar epithelial cell counts, but there were no differences in any soluble marker studied. When compared to control subjects, both the asthmatic and COPD subjects had raised eosinophil counts and ECP levels. In a subset of COPD subjects with sputum eosinophilia (>3% of total cells), significantly increased levels of tryptase were detected. In conclusion, although chronic obstructive pulmonary disease is a more neutrophilic disease than asthma, the two diseases are difficult to distinguish on the basis of sputum levels of the soluble markers traditionally associated with asthma. However, a subset of patients with chronic obstructive pulmonary disease with airway eosinophilia and mast-cell activation might represent a distinct pathological phenotype.     

Possible Involvement of C-C Chemokines in Functional Augmentation of Adhesion Molecules in Asthmatic Patients

Adhesion molecules and C-C chemokines play an important role in the accumulation of eosinophils in allergic inflammation. In the present study, the expression and function of adhesion molecules on eosinophils from asthmatic patients and involvement of RANTES and eotaxin were examined. Eosinophils isolated by the CD16 negative selection method were stimulated with or without RANTES or eotaxin. Expression of b integrins on eosinophils and the functional adherence to recombinant soluble intercellular adhesion molecule-1 (r-sICAM-1)-coated plates were examined. Compared with normal subjects, eosinophils from asthmatic patients showed increased expression of b2 integrins and functional adherence to r-sICAM-1-coated plates. RANTES and eotaxin augmented the functional adherence of eosinophils without a significant upregulation of b2 integrins. Anti-b2 integrin antibody inhibited the augmentative effect on eosinophil adherence of RANTES and eotaxin. Pertussis toxin, wortmannin, and genistein inhibited chemokine-induced adherence. RANTES and eotaxin are closely related to eosinophil accumulation not only as chemotactic agents but also as augmentative agents for eosinophil adherence through involvement in functional eosinophil adherence to ICAM-1 by a possible qualitative change of b2 integrins. Pertussis toxin-sensitive G proteins, PI3 kinase, and tyrosine kinase are involved in signal transduction leading to activation of b2 integrins on eosinophil following stimulation with RANTES and eotaxin.