Eosinophil granule proteins in serum after allergen challenge of asthmatic patients and the effects of anti-asthmatic medication

Thirteen allergic asthmatic patients were challenged six times each and serum levels of ECP (eosinophil cationic protein), EPX (eosinophil protein-x) and blood counts of eosinophil granulocytes were measured in blood obtained before and at regular intervals after challenge. Three challenges were performed in a blinded and randomized fashion and included a one-dose pretreatment with the inhalant anti-asthmatic drugs disodium cromoglycate, terbutaline and budesonide. One challenge was performed after 4 weeks' pretreatment with the inhalant budesonide and one was a histamine challenge. Pre-challenge levels of ECP were significantly reduced both after 4 weeks and after a one-dose treatment with budesonide whereas the EPX levels were reduced only after the former. Blood eosinophil counts were unaffected by the challenge whereas the ECP levels were significantly reduced after the placebo challenge and when premedicated with disodium cromoglycate and terbutaline. The EPX levels stayed unaltered at the placebo challenge but were significantly reduced when the patients were premedicated with terbutaline. ECP and EPX levels as well as blood eosinophil counts before challenge were significantly related to the development of the late asthmatic reaction. The results again focus on a relation between the eosinophil granulocyte and asthma and suggest that an increased activity of the blood eosinophil, as suggested by the raised serum levels of the granule proteins ECP and EPX, is one prerequisite for the development of chronic asthma.     

Airway inflammation in asthma and perennial allergic rhinitis. Relationship with nonspecific bronchial responsiveness and maximal airway narrowing

BACKGROUND: Eosinophilic airway inflammation is the hallmark of asthma, but it has also been reported in other conditions such as allergic rhinitis. We have tested whether the analysis of cells and chemicals in sputum can distinguish between patients with mild allergic asthma, those with allergic rhinitis, and healthy controls. The relationship between inflammation markers in sputum and nonspecific bronchial hyperresponsiveness to methacholine (BHR) (PD20 and maximal response plateau [MRP] values) was also evaluated. METHODS: We selected 31 mild asthmatics and 15 rhinitis patients sensitized to house-dust mite. As a control group, we studied 10 healthy subjects. Every subject underwent the methacholine bronchial provocation test (M-BPT) and sputum induction. Blood eosinophils and serum ECP levels were measured. Sputum cell differentials were assessed, and eosinophil cationic protein (ECP), tryptase, albumin, and interleukin (IL)-5 levels were measured in the entire sputum supernatant. RESULTS: Blood eosinophils and serum ECP levels were higher in asthma patients and rhinitis than in healthy controls, but no difference between asthma patients and rhinitis patients was found. Asthmatics had higher eosinophil counts and higher ECP and tryptase levels in sputum than rhinitis patients or control subjects. Sputum albumin levels were higher in asthmatics than in controls. Rhinitis patients exhibited higher sputum eosinophils than healthy controls. An association between sputum eosinophil numbers and MPR values (r= -0.57) was detected, and a trend toward correlation between sputum ECP levels and PD20 values (r= -0.47) was found in the rhinitis group, but not in asthmatics. No correlation between blood eosinophilic inflammation and lung functional indices was found. CONCLUSIONS: Induced sputum is an accurate method to study bronchial inflammation, allowing one to distinguish between rhinitis patients and mildly asthmatic patients. The fact that no relationship was detected between sputum inflammation and BHR suggests that other factors, such as airway remodeling, may be at least partly responsible for BHR in asthma.     

The influence oc glycocorticoid therapy on sputum ECP concentration in symptomatic patients with bronchial asthma

ECP released from the granules of activated eosinophils is regarded to be a marker of airway inflammation in asthma. The study was performed to compare the usefulness of measuring serum and sputum ECP for monitoring the asthma treatment. 29 subjects with mild to moderate asthma (mean age 41 +/- 17) were admitted in exacerbation (FEV1 55.54 +/- 87.49% N). 10 subjects with grass pollen asymptomatic asthma and 10 healthy subjects were also enrolled in the study. Patients with symptomatic asthma were ordered 30 mg prednisone for 2 weeks and they continued during next 2 weeks inhaled budesonide therapy. The concentrations of ECP (mcg/L) were determined by CAP-system (Pharmacia). The total eosinophil count and serum ECP in all subjects treated orally and next by inhaled GKS didn't differ statistically. The highest sputum ECP concentration was determined in exacerbation of asthma 84.5 +/- 78 mcg/L and statistically were reduced after 2-weeks of prednisone treatment 24.4 +/- 12.1 mcg/L (p = 0.05). In following 2 weeks of budesonide treatment sputum ECP concentration was statistically negligible in relation to previous treatment in spite of increasing tendency (50 +/- 61.3 mcg/L (p = 0.2394). In asymptomatic grass pollen asthma sputum ECP concentration was 19.7 +/- 9.4 mcg/L, higher than in controls 12 +/- 5.8 mcg/L (p = 0.04). There were a significant correlations between total eosinophil count and serum (r = 0.6396) and sputum ECP(r = 0.4683) in exacerbation. CONCLUSIONS: 1. In asthma exacerbation elevated sputum ECP concentration was observed. 2. In consequence of prednisone treatment the sputum ECP concentration was reduced. 3. Sputum ECP measurement is more accurate than serum ECP for monitoring the effectiveness of treatment. 4. Sputum ECP concentration is a sensitive parameter which discriminate asymptomatic patients with asthma from healthy subjects.     

Nitric oxide metabolites,eosinophils, and eosinophilic cationic protein in patients with asthma: sputum versus blood

The monitoring of airway inflammation has assessed in bronchial asthma directly by sputum examination, and indirectly by measurements in peripheral blood. To investigate the diagnostic value of these two methods, we compared nitric oxide (NO) metabolites, eosinophils, and eosinophil cationic protein (ECP) in sputum and blood in patients with asthma and control subjects. Sputum and serum were obtained from fifteen patients with asthma, and then were examined before anti-asthma treatment, including steroid preparations. ECP was measured by fluoroimmunoassay. NO metabolites were assayed by using modified Griess reaction. Asthmatic patients, compared with control subjects, had significantly higher level of NO metabolites, higher proportion of eosinophils, and higher levels of ECP in sputum. Asthmatic patients, compared with control subjects, however, had significantly higher number of eosinophils, and were at higher levels of ECP in blood. FEV1, FEV1/FVC was negatively correlated with sputum eosinophils. The area under receiver operating characteristic (ROC) curve showed that eosinophils in sputum are significantly accurate markers than NO metabolites in sputum and blood. These findings suggest that the proportion of eosinophils in sputum have more accurate diagnostic marker of asthmatic airway inflammation than NO metabolites in sputum in differentiating asthmatic patients from control subjects.     

Relationship between induced sputum cell counts and fluid-phase eosinophil cationic protein and clinical or physiologic profiles in mild asthma.

BACKGROUND: Sputum analysis is the only non-invasive method to examine airway inflammatory processes in subjects with asthma. The aim of this study was to investigate the relationship between cell counts and fluid phase levels in induced sputum in subjects with mild asthma, and the severity of asthma as assessed by clinical, physiologic and blood measurements. METHODS: Forty patients with mild asthma, aged 17 to 49 years were studied (good sputum sample only from 31). On the first day, spirometry and methacholine challenges were performed. After 2 to 4 days, venous blood for absolute eosinophil count and eosinophil cationic protein (ECP) measurement was obtained and sputum was induced by inhalation of hypertonic saline. For the next 15 days subjects recorded their peak expiratory flow (PEF), symptom scores, and beta2-agonist requirements twice daily. Differential counts of leukocytes were done on cytospin preparations of homogenized sputum and the supernatant was examined for eosinophil cationic protein (ECP). RESULTS: Sputum eosinophil counts and not neutrophil, epithelial cells, macrophages, or lymphocytes, were inversely correlated to FEV1/FVC % (r = -.57, P = .0008) and to PC20-methacholine (r = -.40, P = .024). No statistical relationship was obtained between eosinophil counts and either symptom scores, bronchodilator requirements, or daily PEF variability. Sputum ECP values were correlated to FEV1/FVC% (r = -.41, P = .026) but not to PC20 (r = -.32, P = .08) or clinical scores or PEF variation. A trend to significance was appreciated between peripheral blood and sputum eosinophil counts (r = .34, P = .067) and no relationship was found between sputum and serum ECP values (r = .10, P = .38). CONCLUSIONS: Although sputum markers give some information about disordered lung function and physiologic changes in the airways, they are not the only factors concerned in the clinical expression of mild asthma.     

Eosinophil markers in blood, serum, and urine for monitoring the clinical course in childhood asthma: impact of budesonide treatment and withdrawal

BACKGROUND: Markers of airway inflammation are needed for prediction of asthma deterioration and evaluation of disease severity. Few studies have focused on the dynamics of airway inflammation as reflected by the activity of the eosinophils and their proteins after withdrawal of inhaled corticosteroids. OBJECTIVE: Our goal was to investigate the effect of withdrawal of inhaled budesonide on eosinophil count in blood and eosinophil proteins in serum and urine and to relate the levels of these markers to the risk of symptoms of asthma, increased bronchial hyperresponsiveness, and deterioration of lung function. METHODS: Thirty-three children were randomly selected to continue or discontinue use of inhaled budesonide in a double-blind, placebo-controlled study. They were followed up for 4 months with regular analysis of blood, serum, and urine samples; lung function; and methacholine challenges. Eosinophil activity markers were analyzed. Age-matched healthy children provided reference data for all parameters measured. RESULTS: The eosinophil number in blood and eosinophil protein levels in serum (serum eosinophil cationic protein [ECP] and serum eosinophil peroxidase [EPO]) increased significantly in the withdrawal group, and the difference between the groups was significant (P =.02 for all). Twenty-nine percent of the children in the withdrawal group remained symptom free. This subgroup had eosinophil counts at baseline below 350/microL, a serum ECP level below 15 microg/L, and a serum EPO level below 25 microg/L, each of which was related to a low risk of exacerbation (relative risk = 0.37, 0.48, and 0.37 respectively; P <.05 for all). All eosinophil markers were lower in the healthy children than in the symptom-free children with asthma. CONCLUSION: Our data indicate that eosinophil count and/or ECP and EPO levels can be used to estimate the short-term risk of deterioration and the need for corticosteroid treatment in cases of mild and moderate allergic asthma.     

维生素D3上调蛋白1在哮喘嗜酸粒细胞中的表达及其与细胞活化的关系

目的: 探讨维生素D3上调蛋白1（VDUP1）在哮喘患者外周血嗜酸粒细胞（EOS）中的表达及与EOS活化的关系。方法: 实验分为对照组、哮喘发作组和缓解组。抽取外周静脉血15 mL，计算诱导痰EOS%，测定第1秒最大呼气量占预计值百分比（FEV1.0%）和最大呼气中期流速占预计值百分比（PEF%）；ELISA法检测血清嗜酸粒细胞阳离子蛋白（ECP）浓度。RT-PCR及Western blotting方法检测外周血EOS VDUP1表达情况。IL-5 与EOS共孵育，检测EOS VDUP1表达情况，ELISA法检测培养上清液ECP浓度。结果: 哮喘发作组外周血EOS VDUP1表达均显著低于正常组及缓解组，与诱导痰EOS%及血清ECP浓度呈明显负相关；缓解组基因表达与正常对照组无显著差异，与上述指标也无明显相关。IL-5刺激下，EOS VDUP1表达明显降低，同时伴上清ECP明显升高。结论： 哮喘发作时外周血EOS VDUP1表达明显下调，EOS VDUP1表达与血清ECP及诱导痰EOS%呈明显负相关，IL-5促进EOS活化可能与VDUP1通路有关。     

Once-daily theophylline reduces serum eosinophil cationic protein and eosinophil levels in induced sputum of asthmatics

BACKGROUND: Because eosinophilic airway inflammation is a characteristic feature of bronchial asthma, the treatment of airway inflammation is important in the management of asthma. Theophylline has been reported to reduce airway inflammation, in addition to its well-known bronchodilating effect. OBJECTIVE: In order to evaluate the effects of theophylline on airway inflammation, we investigated 48 subjects with mild and moderate asthma. METHODS: The patients were randomly divided into two groups, with or without theophylline treatment (control n = 24; theophylline, n = 24). We examined the level of serum eosinophil cationic protein (ECP), induced sputum samples, and peak expiratory flow (PEF) and obtained spirograms before and after 4 weeks of treatment with once-daily theophylline (200-600 mg/day) of subjects with mild or moderate asthma. RESULTS: Theophylline significantly increased morning and evening PEF and significantly decreased the diurnal variation of PEF. After treatment with theophylline, both serum ECP and the percentage of eosinophils in induced sputum were significantly decreased. In contrast, peripheral blood eosinophil count was unchanged after treatment with theophylline. Conclusions: These findings suggest that theophylline reduces airway inflammation and the severity of asthma, presumably via suppression of both eosinophil activity and subsequent eosinophil infiltration of the airways.     

Detection and treatment of early asthma

Background: We sought answers to two questions: 1) how can mild, early asthma best be detected? 2) how should it be treated and the treatment effect monitored? Methods: Eighty adult patients with early, mostly mild asthma and 30 control subjects were examined by lung‐function and biochemical tests. Patients were randomly assigned to two treatment groups. One group was treated with an inhaled steroid (budesonide) for 6 weeks, and the other first with an inhaled β₂‐agonist (terbutaline) for 6 weeks and then with an inhaled steroid for 2 weeks. Results: Treatment with budesonide was effective: symptom scores, PEF, blood eosinophils, and sputum ECP values all improved. Terbutaline was ineffective by these criteria. For the detection of early asthma and for the following treatment effects, sputum and serum ECP assays are useful supplements to lung‐function tests. Conclusions: Treatment of early, mild asthma with an inhaled steroid is effective and worthwhile. Detection of the disease remains a problem, as both lung‐function and biochemical tests have low sensitivities.     

Eosinophils in exercise-induced asthma

The variations in serum levels of eosinophil cationic protein (ECP) have been measured after exercise challenge of 13 patients with asthma with exercise-induced asthma (EIA) and nine patients with asthma without EIA. The patients were treated before exercise in a randomized and blinded fashion with inhalation of one dose of either disodium chromoglycate, terbutaline, or budesonide and in an open study with 4 weeks of inhaled budesonide. In the group with EIA, there was, in some patients, an initial increase in serum levels of ECP after exercise, but 60 minutes after exercise, the levels were significantly reduced (p less than 0.001). Disodium chromoglycate and 4 weeks of budesonide treatment inhibited this reduction. Histamine challenge of the group with EIA produced a similar fall in serum ECP levels (p less than 0.001). The group without EIA had initially lower levels of ECP than the group with EIA (p less than 0.05 to p less than 0.01), and ECP stayed unaltered after exercise. The preexercise serum ECP levels correlated significantly to the maximal fall in peak expiratory flow in the untreated group (r = 0.91; p less than 0.001) and in the group receiving one dose of budesonide (r = 0.62; p less than 0.05). The blood eosinophil counts were unchanged after challenge and not related to lung function. The results suggest that the ECP content in serum reflects the degree of allergic inflammation in the lungs and thereby the degree of bronchial hyperreactivity.     

The small airway inflammation of asthmatic patients who have used dry powder type inhaled steroid for moderate-long term evaluated by induced sputum and the efficacy of HFA-BDP (QVAR) inhalation]

Although the dry powder type inhaled steroids, such as Fluticasone Propionate Diskhaler (FP-DH), FP Diskus (FP-DK), Budesonide Turbuhaler (BUD-TH), are widely distributed in daily clinical fields, we clinicians are required to evaluate whether it is effectively inhibiting inflammation of distal airway or not. We also investigated the effect of Hydrofluoroalukan-beclomethasone dipropionate (HFA-BDP), a new type of inhaled steroid which forms super micro aerosol particles, in the distal small airway. METHOD: 85 patients with moderate asthma, who daily used dry powder type inhaled steroid for at least more than 6 months with stable asthmatic condition, were the subject of this study. All subjects underwent sputum induction with the inhalation of 10% of hypertonic saline solution for 15 min and eosinophil counts and eosinophil cationic protein (ECP) in individual induced sputum were measured. Then, patients who had eosinophils detected in their induced sputum changed their previously inhaled steroid to HFA-BDP inhalation (400 i.g./day). Their eosinophil counts and the values of eosinophil cationic protein (ECP), Eotaxin, RANTES and neutrophil elastase (PMN-E) in their induced sputum were also examined before and 4weeks after changing HFA-BDP inhalation. RESULT: Increased eosinophils were found in the induced sputum of 40.5% patients of the FP-DK group, 36.3% of the FP-DH group and 32.4% of the BUD-TH group, respectively. Compared with group of patients in which no sputum eosinophil were detected, the sputum ECP values, in which sputum eosinophils were detected, were significantly high. 4 weeks after changing to HFA-BDP inhalation, eosinophil counts, ECP, Eotaxin, RANTES and PMN-E in their induced sputum were decreased in every group. CONCLUSION: Compared with the ordinary dry powder type inhaled steroids, HFA-BDP can effectively diminish distal airway inflammation, suggesting the possibility that HFA-BDP can effectively reach to the distal small airway by forming super micro aerosol particles.     

Eosinophil cationic protein in patients with bronchial asthma]

To evaluate the role of eosinophils in the pathogenesis of bronchial asthma, we measured eosinophil cationic protein (ECP), one of the eosinophil granule proteins. Serum ECP levels were measured by radioimmunoassay in asthmatic (n = 59) and non-asthmatic (n = 47) patients. Preliminary study showed that ECP levels were time-dependently increased in the blood samples until 3 hr. Based on the findings, we determined to measure serum ECP levels at 30 min after blood sampling. Serum ECP levels and blood eosinophil counts in asthmatic patients were significantly higher than those in non-asthmatic patients (p less than 0.01). There was also a positive correlation between serum ECP levels and blood eosinophil counts in patients with asthma (r = 0.46, p less than 0.001). No significant difference was observed in either serum ECP levels or blood eosinophil counts in asthmatic patients classified by clinical type and severity. Blood eosinophil counts in patients with asthma attacks were significantly greater than in those in remission (p less than 0.05), but no significant difference was observed in serum ECP levels between these groups, suggesting an enhanced elimination of ECP during attack. Serum alpha-2 macroglobulins, which bind to ECP and may function as scavengers for ECP, were not significantly different in these group. These results suggest that serum ECP levels may not be a direct indicator of eosinophil activation or degranulation in the pathogenesis of asthma.     

Correlation between airway hyperresponsiveness and airway inflammation in a young adult population: eosinophil, ECP, and cytokine levels in induced sputum.

BACKGROUND: Eosinophil counts and eosinophil cationic protein (ECP) levels in the airway are elevated in asthmatic patients. However, few studies have examined the correlation between various cytokines in the sputum and airway hyperresponsiveness (AHR) in young adults with or without asthma. OBJECTIVE: We examined the correlation between AHR and eosinophil counts or ECP, and levels of several cytokines in the sputum. METHODS: We studied 120 nonsmoker students (group 1: intermittent mild asthmatic patients; group 2: subjects with history of childhood asthma; group 3: subjects sensitized by Dermatophagoides farinae with atopic disease; group 4: normal subjects sensitized by D. farinae; group 5: subjects with cedar pollinosis; and group 6: normal subjects). In each subject, AHR and lung function tests were measured, together with eosinophil count, ECP, granulocyte-macrophage colony-stimulating factor, TNF-alpha, IL-5, and interleukin-1beta in induced sputum. RESULTS: AHR in groups 1 and group 2 were high, in groups 5 and 6 low, and in groups 3 and 4 lower than in groups 1 and 2 but higher than groups 5 and 6. Percentages of eosinophils, ECP, and TNF-alpha in induced sputum in groups 1 and 2 were high, those in groups 5 and 6 were below detection limits, and those in groups 3 and 4 were lower than the percentages in groups 1 and 2. Granulocyte-macrophage colony-stimulating factor in the sputum was elevated only in group 1. The correlations between AHR and sputum eosinophil count, ECP, and TNF-alpha were significant, with the strongest correlation with TNF-alpha. CONCLUSIONS: Our results suggest that TNF-alpha levels in the sputum play an important role in determining the severity of AHR in young individuals. Further once AHR develops, it does not disappear, and the severity of airway inflammation influences the extent of AHR.     

Eosinophil activation in acute asthma attacks evaluated by electronmicroscopic findings of eosinophils and the concentration of eosinophil cationic protein in sputum]

We evaluated the activation of eosinophils in the airways of patients with acute asthma attacks by measuring the concentration of sputum eosinophil cationic protein (ECP) and changes in the electron densities of the eosinophil specific granules in sputum. In six hospitalized patients with asthmatic attacks, sputum samples were collected for seven consecutive days after admission and were used for the evaluation of eosinophil activation. The concentration of sputum ECP, the incidence of changes in the electron densities of eosinophil specific granules and the severity of asthma attacks were highest on the day of admission and decreased in association with each other after treatment. A significant correlation was found between the concentration of sputum ECP and the incidence of changes in the electron densities of eosinophil specific granules. These findings suggest that the eosinophils in the airways are markedly activated and degranulated in asthma attacks.     

Effects of low dose fluticasone/salmeterol combination on surrogate inflammatory markers in moderate persistent asthma

BACKGROUND: Noninvasive surrogate markers provide valuable information on the asthmatic inflammatory process. We wished to examine the effects of low dose fluticasone/salmeterol combination on different commonly used inflammatory markers in moderate persistent asthma. METHODS: Twenty-five moderate persistent atopic asthmatics were enrolled of whom 20 completed an open label study. Following an initial 4 week steroid washout period in which patients took salmeterol 50 microg dry powder inhaler 1 puff BD, they received the addition of fluticasone as fluticasone 100 microg/salmeterol 50 microg combination dry powder inhaler 1 puff BD for the next 2 weeks. Exhaled nitric oxide, spirometry, methacholine PD20, sputum/blood eosinophils and sputum/serum eosinophil cationic protein (ECP) were measured following the salmeterol only and fluticasone/salmeterol combination treatment periods. RESULTS: Compared to salmeterol alone (i.e. after the steroid washout), the use of fluticasone/salmeterol combination conferred significant improvements (P < 0.05) in all surrogate markers of inflammation apart from serum ECP. Geometric mean fold changes were 4.3-fold/1.3-fold for sputum/blood eosinophils, 2.2-fold/1.2-fold for sputum/serum ECP, 2.3-fold for methacholine PD20 and 1.8-fold for exhaled nitric oxide. CONCLUSIONS: Surrogate markers apart from serum ECP may be used as a guide to evaluate the anti-inflammatory effects of low dose inhaled corticosteroids. Sputum markers tend to be more sensitive than blood when assessing the anti-inflammatory response.     

Diagnostic accuracy of sputum outcomes in chronic stable asthma

BACKGROUND: Asthma with non-remitting airflow obstruction may not always be differentiated from COPD with airway hyperreactivity. Many attempts have been made to find useful markers for the distinction between these two disorders. OBJECTIVE AND METHODS: In order to help the finding of a useful marker for the diagnosis of asthma in the population of patients with airway obstruction we analysed the diagnostic accuracy of sputum eosinophils and sputum ECP in 91 patients with asthma, 15 patients with chronic bronchitis, 32 patients with chronic obstructive pulmonary disease (COPD) and 20 controls subjects, by performing ROC analysis. RESULTS: Sputum eosinophils were above the normal range of our laboratory (0-3.7%) in 48 asthma patients and in six COPD patients, while sputum ECP (normal range < 85 microg/L) was high in 65 asthma patients, in 24 COPD patients and in nine chronic bronchitis patients. The ROC analysis revealed that sputum eosinophils count (AUC = 0.82) was more accurate than both sputum ECP levels (AUC = 0.56) (P < 0.0001) and beta2-reversibility (AUC = 0.53) (P = 0.0001) in differentiating asthmatic from non-asthmatic subjects (COPD, chronic bronchitis patients and normal subjects). The diagnostic accuracy of ECP was similar to that of bronchial reversibility (P = 0.76). When ROC analysis was performed by including only patients with airway obstruction (36 asthmatics with airway obstruction and COPD patients), both eosinophil count (AUC = 0.77) and beta2-reversibility (AUC = 0.66) were more accurate than ECP measurement (AUC = 0.39) in discriminating asthmatics from COPD patients (P < 0.00001 and P = 0.04, respectively). CONCLUSION: Sputum eosinophils seem to be valid markers for detecting asthma in a population of patients with airway obstruction. Moreover, the higher diagnostic accuracy of eosinophils in the sputum compared to sputum ECP and bronchial reversibility reinforces the role of cytological analysis of sputum in the diagnosis of chronic stable bronchial asthma.     

Significance of the eosinophil cationic protein/eosinophil count ratio in asthmatic patients: its relationship to disease severity.

BACKGROUND: Serum levels of eosinophil cationic protein (ECP) may reflect the degree of bronchial inflammation in patients with asthma, but its clinical value as a parameter for monitoring asthma remains controversial. OBJECTIVE: We measured the ratios of the serum ECP concentrations to peripheral blood eosinophil counts (ECP/Eo ratio) in patients with asthma and evaluated the correlation between these ratios and individual asthma severity. METHODS: The serum ECP concentrations and peripheral blood eosinophil counts were measured by radioimmunoassay and an autoanalyzer, respectively. Each patient with asthma was in remission at the time the serum specimen was obtained. An overall evaluation of asthma severity for each patient was determined by the frequency and severity of asthma attacks and by clinical scores. RESULTS: The ECP/Eo ratio in patients with severe asthma was significantly higher than in those with mild asthma. However, serum ECP concentrations and peripheral blood eosinophil counts were not different among the patients with mild, moderate, or severe asthma. The ECP/Eo ratios correlated significantly with the monthly average of the clinical scores, but the serum ECP concentrations did not correlate with the monthly average of the clinical scores. The ECP/Eo ratios were also increased in patients with more severe asthma whose serum IgE concentrations and peripheral eosinophil counts were not elevated. CONCLUSIONS: The ECP/Eo ratio may be useful in assessing asthma severity; however, the serum ECP concentration or peripheral blood eosinophil count is not useful.     

Clarithromycin suppresses bronchial hyperresponsiveness associated with eosinophilic inflammation in patients with asthma.

BACKGROUND: Although long-term administration of 14-membered macrolide antibiotics is a therapeutic alternative in asthma, both its pharmacologic mechanism of action and association with the pathogenesis of asthma remain obscure. OBJECTIVE: This study investigated the suppressive effect of clarithromycin on airway responsiveness to methacholine provocation testing and examined whether chrarithromycin's antiasthmatic activity is associated with a reduction in eosinophilic inflammation. METHODS: For 8 weeks, patients received 200 mg of clarithromycin or identical-appearing placebo twice daily. We assessed the effects of treatment with clarithromycin on bronchoconstriction precipitated by inhalation of methacholine in 17 adults with mild or moderate bronchial asthma who were in stable clinical condition. A double-blind, randomized, crossover design was used. Eosinophil counts and eosinophilic cationic protein (ECP) levels were determined in blood and sputum samples obtained on the morning of the methacholine provocation testing day. RESULTS: After 8 weeks of treatment with clarithromycin, patients' symptoms, blood and sputum eosinophils counts and sputum ECP levels were significantly decreased compared with both placebo and baseline. Furthermore, values of PC20 methacholine improved in all patients after clarithromycin treatment. CONCLUSIONS: Clarithromycin has a bronchial anti-inflammatory effect associated with decreased eosinophilic infiltration. This study suggests interesting therapeutic possibilities for bronchial asthma that warrant further trials.     

Cromolyn sodium suppresses eosinophilic inflammation in patients with aspirin-intolerant asthma.

BACKGROUND: Although administration of cromolyn sodium is one of the most useful drugs for the treatment of aspirin-intolerant asthma (AIA), both its pharmacologic mechanism of action and association with the pathogenesis remain obscure. OBJECTIVE: This study was designed to investigate the protective effect of cromolyn sodium on airway responsiveness to the sulpyrine provocation test, and to examine whether its activity is associated with a reduction in eosinophilic inflammation. METHODS: Patients were randomly assigned to receive cromolyn sodium (20 mg/2 mL, or 1 ampoule; Fujisawa, Osaka, Japan) or matching placebo (2 mL of saline) four times daily for 1 week. We evaluated the effects of pretreatment with cromolyn sodium on bronchoconstriction precipitated by inhalation of sulpyrine in 16 adult patients with mild or moderate AIA; those who were in stable clinical condition were allocated to this study. A double-blind, randomized, crossover design was used. Blood and sputum samples were taken in the morning on the sulpyrine provocation testing day. Eosinophil counting and measurement of eosinophilic cationic protein (ECP) were performed. RESULTS: Inhaled cromolyn sodium protect against aspirin-induced attacks of asthma through mechanisms not related to the bronchodilator property, but related to the improvement of the bronchial hypersensitivity, almost completely in all patients (P < 0.001). After 1 week's treatment with cromolyn sodium, patients' symptoms, blood and sputum eosinophils counts, and sputum ECP levels were significantly decreased compared with both placebo and baseline. CONCLUSIONS: Cromolyn sodium has a bronchial anti-inflammatory effect associated with decreased eosinophilic infiltration. This is the first report that cromolyn sodium reduces blood and sputum eosinophils counts and sputum ECP levels in AIA.     

Eotaxin in induced sputum of asthmatics: relationship with eosinophils and eosinophil cationic protein in sputum

BACKGROUND: Eosinophilic inflammation is a crucial aspect of allergic diseases such as bronchial asthma. An eosinophil-active chemokine, eotaxin, may play a role in the pathogenesis of the tissue eosinophilia accompanying asthma. METHODS: Induced sputa were obtained from 53 patients with atopic asthma and six healthy subjects, and the concentration of eotaxin in the sputum was measured by ELISA. We investigated whether the sputum content of eotaxin is related to 1) asthma status or corticosteroid therapy, and 2) other sputum indices, including percentage of eosinophils and concentration of eosinophil cationic protein (ECP). RESULTS: The patients with stable or unstable asthma showed significantly higher concentrations of sputum eotaxin than the normal controls. The level of sputum eotaxin demonstrated a positive correlation with the percentage of eosinophils in stable asthmatics not receiving corticosteroid therapy, but not in stable patients treated with corticosteroids, or in unstable patients. Sputum eotaxin demonstrated a positive correlation with ECP in asthmatic patients who were either in a stable state or not receiving steroid therapy. CONCLUSIONS: The elevated level of eotaxin detected in association with increased eosinophils and ECP in the sputum of asthmatics suggests that eotaxin is involved in the pathogenesis of eosinophilic airway inflammation. The relationship of eotaxin to airway eosinophilia may be modified by the stability status of asthma and corticosteroid therapy.