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Notes: 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.

Notes: Bronchoalveolar lavage (BAL) greatly improved our understanding of asthma allowing to demonstrate the key role of inflammation in the pathogenesis of the disease. BAL is a safe procedure, even in severe patients when properly performed. BAL samples large and small airways and alveoli. Cells and mediators may be measured in BALF but they only represent an indirect estimation of the bronchial inflammation. Before performing BAL, the clinical status of the patients should be ascertained and drugs taken may have to be withdrawn. BALF markers should follow some requirements: (I) markers should be released by cells that are pertinent to airways inflammation (and reparation) in asthma, and, if possible they should be specific of a single cell type, (2) the enumeration of cells or titration of the marker or of its metabolites should be specific and sensitive, (3) if possible the titration should not be modified by the sampling procedure, (4)pilot studies should have demonstrated that the cell is incrcased or the secretory product is released during challenge in asthmatic subjects, (5) studies in a large number of patients should have demonstrated that the levels of the marker are increased in chronic asthmatics, that these levels are correlated with the severity of the disease and are decreased during effective anti-inflammatory treatment, and (6) if possible the cell or marker should be specific to asthma (but at present there is no such cell or marker). Eosinophils and granule secretory products follow most of these requirements. BAL represents an important research tool to assess the effects of therapeutic interventions.

Notes: The activation of mast cells is generally considered to be an important trigger mechanism in the immediate allergic response. This study focused on the determination of three markers of mast cell activation after an allergen challenge. Nasal allergen challenges were performed in 25 subjects with seasonal allergic rhinitis using three allergen doses increasing in 10-fold steps in a standardised nasal lavage model for the subsequent recovery of the markers of mast cell activation. The levels of histamine and tryptase in the nasal lavage fluid were determined using radioimmunoassays, while the TAME-esterase activity was determined using a radiochemical technique. The nasal symptoms obtained on challenge were assessed using a scoring technique. The allergen challenge resulted in significant increases in the levels of all three markers, tryptase, histamine and TAME-esterase. In the individual measurements after the challenges there was a highly significant correlation between the TAME-esterase levels and the tryptase levels (r = 0.71; P 〈 0.001), while the generation of histamine and tryptase was not significantly correlated. When comparing the cumulative generation of the three markers, significant correlations were found between all three. Allergen challenges in six non-allergic controls using the same technique did not result in any increase in tryptase levels. The findings suggest that the determination of tryptase in nasal lavage fluid may be a valuable indicator of mast cell activation in the upper airways.

Notes: The activation of mast cells is generally considered to be an important trigger mechanism in the immediate allergic response. This study focused on the determination of three markers of mast cell activation after an allergen challenge. Nasal allergen challenges were performed in 25 subjects with seasonal allergic rhinitis using three allergen doses increasing in 10-fold steps in a standardised nasal lavage model for the subsequent recovery of the markers of mast cell activation. The levels of histamine and tryptase in the nasal lavage fluid were determined using radioimmunoassays, while the TAME-esterase activity was determined using a radiochemical technique. The nasal symptoms obtained on challenge were assessed using a scoring technique. The allergen challenge resulted in significant increases in the levels of all three markers, tryptase, histamine and TAME-esterase. In the individual measurements after the challenges there was a highly significant correlation between the TAME-esterase levels and the tryptase levels (r = 0.71; P 〈 0.001), while the generation of histamine and tryptase was not significantly correlated. When comparing the cumulative generation of the three markers, significant correlations were found between all three. Allergen challenges in six non-allergic controls using the same technique did not result in any increase in tryptase levels. The findings suggest that the determination of tryptase in nasal lavage fluid may be a valuable indicator of mast cell activation in the upper airways.

Notes: Blood eosinophils, and serum levels of the eosinophil proteins, eosinophil cationic protein (ECP) and eosinophil protein X (EPX) were measured in childhood asthma. Seventeen patients mean age 11–9 years who were symptomatic with asthma, were enrolled in a study examining the eosinophil counts and eosinophil proteins at the onset of study and after treatment in relation to changes in their baseline forced expiratory volume at 1 second (FEV1) and % predicted FEV1. The patients with symptomatic asthma were compared with 17 patients mean age 12.0 years with asymptomatic asthma maintained on daily inhaled steroid and 13 patients, mean age 12.0 years, without asthma but with urticaria who served as non-asthma controls. Patients with symptomatic asthma did not have significantly higher initial eosinophil counts compared with those with asymptomatic asthma (0.43 × 109/1 vs 0.26 × 109/1, P= 0.09) but had higher serum ECP levels (28.9 μ/1 vs 18.5 μg/1). Both asthma patient groups had significantly higher serum ECP levels (P〈0.01) than the controls (9.8 μg/1). After therapy consisting of increased dose of inhaled steroids and/or oral steroids, patients in the symptomatic asthma group demonstrated a significant rise in FEV1 (1.67 1/sec at Visit 1 vs 2.08 1/ sec at Visit 2, 1〈0.01). A similar rise was seen for % predicted FEV1. Patients in the asymptomatic asthma group showed no significant change in FEV1 between visits (2.23 1/sec vs 2.37 1/sec), which was verified with the % predicted FEV1, Patients in the symptomatic asthma group showed a significant decrease in ECP level following treatment (28.9 μ/1 to 9.6 μ/1. P〈0.001) while the values in the asymptomatic group did not change (18.6 μ/1 to 15.2 μ/1 not significant). There was a significant correlation between the initial ECP level in the symptomatic asthma group and the change in the FEV| with treatment. Serum EPX levels showed similar trends but there was no significant correlation between the initial EPX levels and the changes in FEV1. Neither did blood eosinophil counts show such a correlation. This data suggests that the changes in serum ECP levels correlate with the changes in lung function subsequently to anti-inflammation therapy.

Notes: Background Lung function tests, including forced expiratory volume in one second (FEV1), forced expiratory flow at 25–75% of vital capacity (FEF25–75%) and provocation concentrations of histamine which reduce FEV] by 20% (PC20), are used as indicators of airway form and function in bronchial asthma. Recently, markers of eosinophil activation in bronchial lavage and serum have been suggested as a measure of eosinophil mediated inflammation in the airways. These include eosinophil cationic protein (ECP), eosinophil protein X (EPX) (also known as eosinophil derived neuro-toxin) and eosinophil peroxidase (EPO). Similarly, serum tryptase has been used as a marker of mast cell activation in systemic anaphylaxis.Objectives We measured both sets of indices in a group of children with moderately severe asthma to assess the contribution of eosinophil and mast cell mediated events to airflow limitation and bronchial hyperresponsiveness.Methods Forty-eight children aged 5–10 years had spirometric assessments, histamine challenges and blood sampling on the same occasion. After analysis of sera, the indices were compared.Results The eosinophil markers ECP and EPX correlated very well with each other. They showed a moderate negative correlation with PC20 for histamine. EPX was also found to negatively correlate with FEV, and FEF25–75%. Serum tryptase levels showed no such correlates with airway function.Conclusion These results suggest that serum markers of eosinophil activation correlate with airway function in childhood asthma, and may be of value in assessing the severity of the disease. It further supports the notion that childhood asthma has a similar immunopathology to that occurring in adults, with predominance of eosinophil mediated inflammation.

Notes: Children less than 5 years of age with asthma were assessed for total eosinophil counts and scrum levels of the eosinophil proteins, eosinophil cationic protein (ECP) and eosinophil protein X (EPX). to determine whether these measurements would reflect eosinophilic inflammation in the airways. Initially 27 symptomatic patients, 14 atopic and 13 non-atopic were investigated. They had a mean age of 1.8 years and had never been treated with inhaled steroid and had not received Intal for 2 weeks prior to the assessment. The 14 atopic patients proved to have higher mean total eosinophil counts and serum levels of ECP and EPX than the 13 non-atopic patients (eosinophil counts 0.63 109/1 vs 0.26 × 109/1, P 〈 0.001; ECP 36.9 μg/1 vs 10.8 μg/1, P 〈 0.001; EPX 69.0 μg/1 v.s 19.6 μg/l, P 〈 0.01. Thirteen of these patients required treatment with daily doses of inhaled steroid and 11 had a repeal assessment (seven atopic and four non-atopic). The mean serum EC'P of the seven atopic patients had fallen significantly (40.6 to 22.9. P 〈 0.05) while the total eosinophil counts did not. These results suggest a difference in numbers and activity of eosinophils in a topic compared with non-atopic asthma in young children.To determine whether the results were influenced by treatment with inhaled steroids. 31 patients who were being treated with daily inhaled steroid underwent assessment when they were symptomatic (22 samples) or asymptomatic (19 samples). Of the 31 patients. 11 were atopic and 20 non-atopic, Atopic asthmatics had higher levels of eosinophils and serum ECP than non-atopic patients when symptomatic patients were compared, despite treatment with inhaled steroid.Finally, in order to determine whether the ECP correlates with atopy rather than asthma, 19 patients who were seen for assessment of a reaction to a food (usually peanut or egg) and who had a positive skin lest to the appropriate food were examined. Twelve of these patients had a history of intermittent asthma and a mean ECP of 31 9μg/I while seven patients had no asthma and a mean ECP of 13.4 μg/l (P 〈 0.05), The total eosinophil counts showed the same difference. This suggests that atopy in the absence of asthma may not be associated with an elevated eosinophil count or ECP level. The data suggest that atopy contributes lo childhood asthma, even in infancy, by mobilization and activation of eosinophils. Scrum ECP might be a useful measure of eosinophil activation in asthma of early childhood.

Notes: A radio immunoassay was developed allowing measurement of the cytotoxic cationic ECP. The assay, which has a total incubation time of 3.5 hr, is a double antibody assay with radiolabelled ECP. covering the concentration range of 2–200 μ/l. Performance data show a detection limit of 〈 2 μg/1 and a cross-reactivity with eosinophil protein X (EPX/EDN) of 〈0.06%. The coefficient of variation (%) within the measuring range was, within assay 4.8–10.4, and total 6.6–12.0. The assay is useful for measurement in various body fluids including serum, nasal secretions and bronchoalveolar lavage fluid, and dilution of samples prior to analysts was generally not required. Sera from 100 apparently healthy individuals revealed a geometric mean of 6.0 μg ECP/1 and a range (95%) of 2.3–15.9 μg/1. The elimination rate of ECP, t12. in vivo was estimated to be 65 min when ECP was measured in serum. Comparisons between this assay and a method previously described showed that the new method is superior with regard to precision and assay procedure.

Notes: We have recetitly phenotyped inflammation iti tion-infectious allergic and non-allergic chronic maxillary sinusitis using sinus biopsies and lavage fluids. In this first paper, we have concentrated our work on the eosinophil, T cell, mast cell and macrophage infiltrates. However, many unresolved questions remain and particularly the role of neutrophils needed to be addressed. In the present study, we focused on the neutrophilic inflammation: myeloperoxidase (MPO) and interleukin-8 (IL-8) were measured by immunoassays and neutrophils were enumerated by conventional staining in the sinus lavage fluids of 16 patients with chronic sinusitis and six control subjects. Both MPO and IL-8 levels were significantly higher in patients than in controls (P 〈 0.01 and 0.005, respectively). There was a significant correlation between MPO levels and neutrophil numbers, and between MPO and IL-8 levels in the sinus lavage fluid (P 〈 0.0001, Spearman rank correlation). The presence of high levels of IL-8 in the lavage fluids of patients suffering from chronic sinusitis, levels which correlate with those of MPO, suggests that this cytokine may activate neutrophils in this chronic disease.