Is intrinsic asthma a hereditary disease?

Although studies of families, inbred populations and twins have established that asthma has a hereditary basis, little evidence has shown that intrinsic asthma has an increased familial occurrence. To document this issue, we compared the prevalence of asthma in families of intrinsic asthmatics, extrinsic asthmatics and non-asthmatics. The intrinsic asthma group included those with negative skin tests to common aero-allergens (n = 117). The extrinsic asthma group included those with one or more positive skin tests (n = 164). The non-asthmatic group (n = 224) was recruited at a check-up center. The siblings of each subject completed a standardized questionnaire on history of asthma. The results showed that asthma was more prevalent (P less than 0.001) in siblings of intrinsic asthmatics (8.9%) than in siblings of the non-asthmatic group (2.4%). The prevalence of asthma in siblings of intrinsic and extrinsic asthmatics was similar. In conclusion, both intrinsic and extrinsic asthma have an increased family occurrence.     

Evaluation of serum eosinophil cationic protein as a predictive marker for asthma exacerbation in patients with persistent disease

BACKGROUND: Eosinophilic inflammation is a feature of asthma. However, serological markers to indicate eosinophil activation in this process are not fully defined. OBJECTIVE: To evaluate the relationship of serum eosinophil cationic protein (ECP) to asthma worsening and a marker for treatment effectiveness, 26 adult patients with an asthma exacerbation were identified. METHODS: Identified asthma subjects were treated with oral corticosteroids (prednisone) for 14 days. The lung function variables, forced expiratory volume in one second (FEV1) and peak expiratory flow (PEF), were determined as percentage of predicted and the blood total eosinophil count and serum ECP levels were measured. Patients were re-evaluated after 14 days of corticosteroid treatment and then every 3 months thereafter during a 12-month period. RESULTS: Eighteen patients responded to prednisone treatment, whereas eight did not, assessed as improvement of their lung function parameters. Different serum ECP patterns could be seen in the responders compared with the non-responders. All 18 responders had considerably increased serum ECP at the time of exacerbation, whereas the non-responders had lower serum ECP levels. The serum ECP levels decreased to a greater extent in the responder patient group than in the non-responder patients following prednisone treatment. This difference in patterns was not seen with total blood eosinophil counts. CONCLUSION: Our findings suggest that serum ECP may be used to predict a response to corticosteroid therapy in adult patients with asthma.     

Expression of CD23 antigen and its ligands in children with intrinsic and extrinsic asthma

The role of the low-affinity IgE receptor CD23 in immune reactions has been further emphasized by recent discoveries of novel surface ligands for CD23: CD21, CD11b, and CD11c. We previously observed the difference between the expression of CD23 and CD21 antigens in children suffering from extrinsic asthma when compared to healthy controls. In the present study, we investigated the expression of CD23 and its ligand CD21 on CD20⁺B cells in 44 asthmatic children (23 allergic and 21 nonallergic) using three-color immunofluorescence analysis. In addition, the expression of two other ligands for CD23, CD11b, and CD11c, on T cells (CD3⁺), a subpopulation of T cells (CD4⁺ and CD8⁺), natural killer cells (CD56⁺), and monocytes (CD14⁺) was tested by two-color immunofluorescence analysis in 12 allergic and 14 nonallergic children. We found that children with extrinsic asthma had higher levels of CD23⁺ B cells than those with intrinsic asthma. No difference was observed in the percentage of either CD23⁺CD21⁺ or CD23^- CD21⁺ B cells. The CD11b antigen was expressed on each tested population, but only on CD4⁺ T cells was CD11b significantly increased in children with extrinsic asthma. CD11c was expressed mainly on monocytes, and no difference was observed between tested groups. The increased percentage of CD11b antigen on CD4⁺ T cells and the increased percentage of CD23 antigen on B cells in children with extrinsic asthma provide further evidence of the immunologic differences between intrinsic and extrinsic asthma.     

Serum eosinophil cationic protein (ECP) as a marker of disease activity and treatment efficacy in seasonal asthma

This study was carried out to determine whether serum eosinophil cationic protein (ECP) represents a sensitive marker for disease activity in atopic asthmatic patients during the pollen season. The study, in double-blind fashion, was performed between February and June 1994. Two groups of 10 seasonal asthmatic patients randomly received two different treatments. The first group was treated with inhaled beclomethasone dipropionate (BDP) 500 μg bid; the second received a matched placebo (P). At the beginning and every month, blood samples for determination of ECP and eosinophil count were collected and lung function (FEV₁) and methacholine responsiveness (PD₂₀) were performed. Subjects recorded daily symptoms of asthma, salbutamol consumption, and peak expiratory flow (PEF) values. In the P group, all indices, except FEV₁, showed significant changes during the pollen season ( P < 0.001). In the BDP group, significant changes were detected for symptom score ( P < 0.01), salbutamol consumption ( P < 0.01), and eosinophil number ( P < 0.05). Between the two groups, significant differences for symptom score ( P < 0.001), salbutamol consumption ( P < 0.001), ECP levels ( P < 0.05), eosinophil count ( P < 0.02), PD₂₀ methacholine ( P < 0.02), and PEF values ( P < 0.01) were detected. Changes in serum ECP significantly correlated with changes in other parameters ( P < 0.001), except FEV₁. Our results provide evidence that serum ECP is a sensitive marker for monitoring of the disease activity in seasonal asthma. Furthermore, it may offer a useful tool for estimating treatment efficacy.     

Soluble CD23 (sCD23) serum levels and lymphocyte subpopulations in peripheral blood in rhinitis and extrinsic and intrinsic asthma

To determine serum levels of IgE and sCD23 and lymphocyte subpopulations, we studied 37 control subjects and 84 patients (27 with allergic rhinitis, 27 with extrinsic asthma, and 30 with intrinsic asthma). A rise in surface CD23 on B and monocyte cells and sCD23 serum levels was exhibited by patients with rhinitis and extrinsic asthma. Unexpectedly, in intrinsic asthmatic patients, high CD23 expression on monocytes and high sCD23 levels were seen that did not result in IgE production. It appears that CD23, in its soluble form, could be a good disease marker, especially in asthma. Atopic patients yielded a significantly lower proportion of CD4⁺ T cells than intrinsic asthmatic patients and normal persons. Otherwise, CD4⁺ CD29⁺ CD45RA - and CD4⁺ CD29 – CD45RA ⁺ T-cell subsets were significantly decreased in all patient groups.     

Local release of eosinophil peroxidase following segmental allergen provocation in asthma

BACKGROUND: Eosinophil peroxidase (EPO) is an eosinophilic basic protein, which leads to increased permeability and damage of bronchial epithelial cells in asthma. OBJECTIVE: As little is known about its local expression and release in humans the intracellular expression in lung and peripheral eosinophils and the concentrations of EPO in bronchoalveolar lavage (BAL) fluid and serum was investigated in patients with asthma. METHODS: Twelve mild atopic asthmatic and nine control subjects underwent segmental sham and allergen challenge. EPO concentrations in BAL fluid and serum were determined by immunoassay and flow cytometry was used to determine the intracellular expression of EPO in BAL-derived and peripheral eosinophils. RESULTS: In asthmatic patients a large increase in BAL eosinophils--total cells: median 9.5 x 10(6) (range: 0.5 to 455.0 x 10(6)); relative: 38% (1 to 91%)--was detectable 24 h following allergen challenge, but peripheral blood eosinophil counts did not change. Concentrations of EPO in BAL fluid increased from 1 microg/L (1.0 to 6.8 microg/L) to 42 microg/L (5.6 to 379.6 microg/L; P < 0.01) after allergen but not after saline challenge (1.5 microg/L; 1.0 to 21.9 microg/L), whereas in control subjects all measurements were below the detection limit. Serum concentrations of EPO increased slightly from 18.3 microg/L (3.0 to 56.8 microg/L) to 27 microg/L (3.8 to 133.9 microg/L; P < 0.05) 24 h after allergen challenge in asthmatic patients. Furthermore, the intracellular expression of EPO (measured as mean fluorescence intensity) was decreased in BAL eosinophils compared with blood eosinophils (mean fluorescence intensity 29 (7 to 71) vs. 48 (20 to 85); P < 0.01) after allergen challenge. CONCLUSION: The finding of increased EPO concentrations in the BAL fluid and decreased intracellular EPO expression in pulmonary eosinophils of asthmatic patients reflects the allergen-triggered release of EPO into the bronchial space.     

Urinary eosinophil protein X in relation to disease activity in childhood asthma

Lugosi E, Halmerbauer G, Frischer T, Koller DY. Urinary eosinophil protein X in relation to disease activity in childhood asthma.
The clinical use of urinary eosinophil protein X 'U-EPX' measurements in monitoring inflammation in childhood asthma was investigated. U-EPX and pulmonary function were assessed in 80 children with bronchial asthma and 24 healthy, age-matched controls. In addition, 14 patients with asthma were re-examined after 1–2 months. U-EPX levels were increased in children with asthma compared with controls 'median 68.4 vs 35.3 μg/mmol creatinine; P < 0·0001'. In addition, U-EPX levels were higher in symptomatic than in asymptomatic patients 'median 123.5 vs 48·9 μg/mmol creatinine; P < 0·0001' independent of treatment modalities 'i.e., inhaled steroids or disodium cromoglycate' or atopy 'median 65.1 vs 86·0 μg/mmol creatinine'. Furthermore, U-EPX levels were significantly correlated with pulmonary function. During the follow-up period, changes in U-EPX values were significantly related to changes in pulmonary function. In conclusion, our findings demonstrate that eosinophil activation can be measured in urine in childhood asthma. Concentrations of U-EPX are related to disease activity and pulmonary function, as shown in both cross-sectional and longitudinal analyses, but are independent of atopy and treatment modalities. Measurement of U-EPX may be useful in assessing the inflammatory process and therefore in the management of childhood asthma.     

Cysteinyl-leukotrienes contribute to sputum eosinophil chemotactic activity in asthmatics

BACKGROUND: Cysteinyl-leukotrienes are lipid derived mediators involved in asthma. They are able to stimulate eosinophil chemotaxis in vitro. Induced sputum from asthmatics has been shown to contain eosinophil chemotactic activity. The purpose of our study was to evaluate the contribution of cysteinyl-leukotrienes to sputum eosinophil chemotactic activity in asthmatics and to seek whether there might be differences between asthmatics free of inhaled corticosteroids vs those regularly receiving this treatment. METHODS: Twenty-two patients (11 corticosteroid free, mean FEV1 99% predicted, 11 corticosteroid-treated, mean FEV1 77% predicted) recruited from our asthma clinic underwent a sputum induction. Sputum was processed according to standard procedure. Eosinophil chemotactic activity contained in the fluid phase was assessed using Boyden microchamber model and expressed as chemotaxis index (CI). Cysteinyl-leukotrienes were measured in sputum supernatant by ELISA and their role in sputum eosionophil chemotactic activity was evaluated by using montelukast, a selective antagonist of a cys-LT1 receptor. RESULTS: Cysteinyl-leukotrienes were well detectable in sputum supernatants from both steroid-naive (247 +/- 42 pg/ml) and steroid-treated (228 +/- 26 pg/ml) asthmatics. Sputum eosinophil chemotactic activity was indiscriminately present in both corticosteroid-naive (CI: 2.61 +/- 0.22) and corticosteroid-treated (2.98 +/- 0.35) asthmatics. Montelukast (100 microM) significantly inhibited the eosinophil chemotactic activity in both groups achieving a mean inhibition of 54.2 +/- 9.2% (P < 0.001) and 64.7 +/- 7.8% (P < 0.001) in steroid-naive and steroid-treated asthmatics respectively. CONCLUSION: Cysteinyl-leukotrienes actively participate in sputum eosinophil chemotactic activity found in asthmatics irrespective of whether they are or not under treatment with inhaled corticoids.     

嗜酸性粒细胞募集在支气管哮喘发病中的作用

支气管哮喘是一种气道慢性炎症性疾病,伴有嗜酸性粒细胞增多、杯状细胞肥大、黏液分泌增多、可逆性的气道阻塞及对吸入变应原和非特异性刺激的高反应性等特点,其中嗜酸性粒细胞募集和随后的激活在支气管哮喘发病中起着十分重要的作用。本文就嗜酸性粒细胞募集在支气管哮喘发病机制中的研究进展作一综述,为支气管哮喘的治疗提供一线新的曙光。     

Sputum eosinophil counts and eosinophil cationic protein levels in cough-variant asthma and in classic asthma, and their relationships to airway hypersensitivity or maximal airway response to methacholine

Background:  The aims of this study were to compare the degree of airway inflammation in cough-variant asthma (CVA) with that in classic asthma (CA), and to examine the relationship between airway inflammation and airway hypersensitivity or maximal airway response to methacholine in both conditions.
Methods:  Sputum was induced in 41 CVA patients, in 41 methacholine PC₂₀-matched CA patients, and in 20 healthy children. The sputum samples were analyzed for total and differential cell counts, and for eosinophilic cationic protein (ECP). A high-dose methacholine challenge test was performed in CVA and CA patients to determine PC₂₀ and maximal airway response.
Results:  Sputum eosinophil percentages and ECP levels were significantly elevated in CVA and CA vs the control, but no significant differences were found between the two asthma groups. In the two asthma groups, neither sputum parameters correlated significantly with methacholine PC₂₀. However, the absence of a maximal response plateau or its higher level, when present, was associated with increased eosinophil percentages and ECP levels in the CVA group.
Conclusions:  The degree of eosinophilic inflammation may not be causally related to differences in presented asthma manifestations. The identification of a maximal response plateau and the level of this plateau in patients with CVA may provide information pertinent to airway eosinophilic inflammation.     

Serum eosinophil granule proteins predict asthma risk in allergic rhinitis

Background: Allergic rhinitis is a common disease, in which some patients will deteriorate or develop asthma. It is important to characterize these patients, thereby offering the possibility for prevention. This study evaluated eosinophil parameters as potential indicators of deteriorating allergic airway disease. Methods: The subjects of the study included all patients who suffered seasonal allergic rhinitis and had participated in a study 6 years earlier, in which blood eosinophils, serum eosinophil cationic protein (ECP) serum eosinophil peroxidase (EPO), nasal lavage ECP and nasal lavage EPO levels were measured. Patients in the present study were interviewed on occurrence of rhinitis symptoms during the last season, rhinitis outside season, asthma‐like symptoms and asthma diagnosis, and were skin‐prick tested for common aeroallergens. Eosinophil parameters from the study 6 years earlier were then tested for the ability to predict occurrence of new allergies, worsening of rhinitis and occurrence of asthma. Results: Forty‐four patients participated in the study. In four patients seasonal rhinitis symptoms had deteriorated, 10 had experienced perennial rhinitis symptoms, 14 reported asthma‐like symptoms and seven had been diagnosed with asthma. Thirteen had developed additional sensitization. Patients developing asthma‐like symptoms compared with patients with no such symptoms had significantly higher serum ECP (16.7 μg/l vs 8.2 μg/l; P ≤ 0.01) and serum EPO (17.9 μg/l vs 8.8 μg/l; P ≤ 0.05). Results were similar, considering patients diagnosed with asthma. Blood eosinophils and nasal lavage parameters were not related to development of asthma and asthma‐like symptoms. No eosinophil parameter was related to deterioration of rhinitis or additional sensitization. Conclusion: Serum ECP and EPO in patients with seasonal rhinitis demonstrated a high predictive ability for later development of asthma.     

Eosinophil activity markers in peripheral blood have high predictive value for bronchial hyperreactivity in patients with suspected mild asthma

The present study aimed to evaluate the predictive value of eosinophils and markers of their activity for bronchial hyperreactivity (BHR) in a population of patients with recently developed clinical symptoms of asthma. The activation of eosinophils was estimated by measuring eosinophil cationic protein (ECP) in serum. In addition, flow cytometry was used to measure the expression of the EG2-epitope on intracellular ECP in eosinophils from peripheral blood. Twenty-eight consecutive patients with clinical history of asthma were studied. Of the 28 patients, 18 had a positive bronchial challenge test measured as PD₂₀≤ 1600 μg histamine. A significantly higher concentration of eosinophils and a trend to higher ECP in the peripheral blood was found in the hyperreactive group than in the nonreactive group. However, the intracellular expression of ECP did not correlate with the PD₂₀ value, and no significant difference between the groups was found. With one eosinophil activity marker, either serum ECP or EG2, BHR could be predicted in 70% of the patients. If we combined any two of the activity markers (serum ECP, EG2, or the percentage of eosinophils), the predictive value increased to 100%. We conclude that the blood eosinophil concentration, as well as, to some extent, serum ECP, has a high specificity for BHR in patients with recently developed clinical symptoms of asthma. Despite normal bronchial reactivity, some patients had signs of activated eosinophils, i.e., high serum ECP and increased EG2 expression. Thus, these markers may reflect early stages in the development of BHR. Our results also indicate that a combined evaluation of percentage of eosinophils and of eosinophil activity markers is of clinical value to predict BHR.     

Airway epithelial type-2 alarmin profiles: Blood eosinophil counts remain in memory

Epithelial cytokines are involved in the orchestration of T1/T2 inflammatory patterns. We question the persistence of this trait in air–liquid interface (ALI) epithelial cultures and whether this local orientation can be related to systemic patterns (e.g., blood eosinophil counts [BECs]). We investigated alarmin release related to high versus low T2 phenotypes associated with chronic airway diseases. ALIs were reconstituted from 32 control, 40 chronic obstructive pulmonary disease, and 20 asthmatic patients. Interleukin-8 (IL-8; a T1-cytokine), IL-25, IL-33, and thymic stromal lymphopoietin (T2-alarmins) concentrations were assessed in subnatants at steady state and used to explain blood neutrophil and eosinophil counts. IL-25 and IL-8 levels were highest in asthma ALI-subnatants, whereas IL-33 was sparsely detected. Thymic stromal lymphopoietin levels were similar among groups. All asthma cell cultures were T1-high/T2-high, while chronic obstructive pulmonary disease and controls tended to be mixed. BECs were independently explained by both disease and in-culture T2-alarmin levels, irrespective of the T2-alarmin considered. The epithelial ALI-T2 signature was more frequently high in patients with a BEC > 300/mm³. Despite removal from an in vivo environment for ≥2 months, ALIs release disease-specific cytokine “cocktails” into their subnatants, suggesting continued persistence of alarmin orientation in differentiated cell line environments.     

Serum eosinophil cationic protein in the evaluation of asthma severity in children

To assess the sensitivity and specificity of serum eosinophil cationic protein (ECP) in the diagnosis of asthma and evaluation of asthma severity, we conducted a prospective study to compare parameters of asthma severity, peripheral blood eosinophilia, and serum ECP concentrations in 88 children presenting to a university hospital outpatient clinic with suspected ( n =59) or recently diagnosed asthma ( n =29). Serum ECP correlated significantly (r²=0.676. P=0.0001) with peripheral eosinophil counts, but only weakly with asthma severity (r,=0.21, P=0.046). Serum ECP was significantly higher in atopic children (25±11 μg/l) than in nonatopic children (16±15 μg/l) iP=0.01). Bronchial hyperresponsiveness had no significant correlation (r_s=-0.21, P=0.30) with serum ECP Lung function test results had no (peak flow) or only a weak (FEV) correlation with serum ECP. In distinguishing between children with and without asthma or in assessing asthma severity, serum ECP is not superior to the peripheral blood eosinophil count. The diagnostic sensitivity and specificity of ECP in serum for detecting symptomatically active asthma, evaluated against the cutoff level of ECP in serum of 16 mg/1, were 54% and 71%, respectively.     

Lack of relationship between eosinophil cationic protein and eosinophil protein X in nasal lavage and urine and the severity of childhood asthma in a 6-month follow-up study.

BACKGROUND: Recent studies suggest that eosinophil cationic protein (ECP) and eosinophil protein X (EPX) may be valuable markers of airway inflammation in various body fluids of asthmatic children. Most of these studies have relied on a single measure of inflammatory markers. OBJECTIVE: We measured ECP and EPX in nasal lavage fluids (NALF) and urine samples in children with asthma over a 6-month period to study the relationship between inflammatory markers and clinical severity. METHODS: Fourteen children with mild persisting asthma (mean age 11.7 years, SD 2.2) were recruited. All patients were on therapy including inhaled steroids. For a 6-month period asthma severity was monitored by at least monthly physical examination and pulmonary function tests. Daily morning and evening PEF, asthma symptoms and medication were recorded in diaries for the whole study period. Telephone interviews were performed between visits and additional visits were done in case of an increase in asthmatic symptoms or drop of PEF values under 80% of best value. An exacerbation was defined by a fall of FEV1 > 10% and an increase in asthma symptoms and additional need of beta2-agonist. NALF and urine samples were obtained at each visit and analysed for ECP (NALF only) and EPX. RESULTS: Mean observation time was 186.4 days (SD 19.8). Thirteen patients completed the study. During the study period 11 exacerbations were observed in six patients. No significant associations between PEF, PEF variability (amplitude % of mean), daily symptoms, additional beta2-agonist, FEV1 and MEF50 and nasal ECP, nasal EPX and urinary EPX were found. However, at exacerbations an average increase of nasal ECP (9.3 vs 50.3 microg/L) and EPX (nasal EPX 36.4 vs 141.7 microg/L, urinary EPX 46.4 vs 74.1 microg/mmol creatinine) was observed. CONCLUSION: Serial measurements of ECP and EPX in NALF and urine samples do not provide additional information for the practical management in monitoring childhood asthma.     

抗白介素5单克隆抗体抑制哮喘小鼠嗜酸性粒细胞迁移

目的 观察抗白介素5(IL-5)单克隆抗体对哮喘小鼠嗜酸性粒细胞(Eos)从骨髓到气道迁移的影响.方法 15只雄性C57BL/6小鼠.常规法复制哮喘,并在每次卵白蛋白(Ova)激发前2 h鼻腔内滴入抗IL-5单克隆抗体,同时设立阴性对照组,即以生理盐水代替Ova 和抗IL-5抗体.在末次抗原激发后12 h测定支气管肺泡灌洗液(BALF)、外周血(PB)和骨髓(BM)中炎症细胞数以及肺组织内Eos数.结果 Ova抗原激发后12 h小鼠的BALF、PB和BM及细支气管和肺组织中的Eos数显著增加(P＜0.01, P＜0.05).抗IL-5单克隆抗体则使上述变化显著减轻(P＜0.05,P＜0.01).结论 抗IL-5单克隆抗体能显著抑制哮喘小鼠嗜酸性粒细胞的迁移.     

Serum eosinophil cationic protein in relation to bronchial asthma in a young Swedish population

How are the serum concentration of eosinophil cationic protein (S-ECP) and the blood eosinophil count (B-Eos) related to symptoms of asthma, allergy, and bronchial hyperresponsiveness (BHR)? We measured S-ECP, B-Eos, and total and specific IgE in serum in blood samples from 699 randomly selected persons 20–44 years old. They also underwent a structured interview, spirometry, a methacholine provocation test, and skin prick tests as part of the European Community Respiratory Health Survey. B-Eos and S-ECP were found to be closely related to asthma symptom score (P < 0.001), total IgE (P < 0.001), and BHR (P < 0.001). On the basis of the results, the subjects were divided into four groups: healthy controls, patients with allergic rhinitis, patients with nonallergic asthma, and patients with allergic asthma. There were significant differences in both B-Eos and S-ECP among the groups (P < 0.001), the highest values being found in the allergic asthma group. B-Eos and S-ECP each had an additive value in predicting the occurrence of asthma. Among persons with high concentrations of both variables, asthma was eight times more common than in those with low concentrations. Allergy and BHR were also found to be independently related to B-Eos and S-ECP levels. Furthermore, both B-Eos and S-ECP showed good correlation to subjective and objective measures of asthma activity. We conclude that both B-Eos and S-ECP and their interrelationship may be of value in assessing the activity of asthma. However, their role in disease management was not established in this cross-sectional study.