The effect of natural pollen exposure on eosinophil apoptosis and its relationship to bronchial hyperresponsiveness in patients with seasonal allergic rhinitis.

BACKGROUND: Limited data suggest that there is increased eosinophilic inflammation in the airways of patients with seasonal allergic rhinitis (SAR) during pollen season even if they do not have asthma. OBJECTIVE: To investigate the effect of natural pollen exposure on inflammatory cells and apoptosis of eosinophils and its association with bronchial hyperresponsiveness (BHR) during and out of pollen season in SAR patients sensitized to only grass pollens. METHODS: Forty SAR patients and 10 patients with nonallergic rhinitis (NAR) from Ankara, Turkey, were recruited to participate in the study. Two induced sputum samples were taken from SAR patients during pollen season (May-June) and out of pollen season (November-January), but only 1 induced sputum sample was taken from NAR patients. Slides of induced sputum were evaluated by 2 cytologists with the use of light microscopy after cytocentrifuged and dyed with May-Grünwald-Giemsa stain. Induced sputum samples were sufficient for differential cell counts in 14 SAR and 7 NAR patients. RESULTS: Eosinophil counts in SAR patients were statistically higher in pollen season (19.4% +/- 16.2%) compared with out of season (4.6% +/- 6.9%, P = .003) and with NAR patients (4.7% +/- 9.5%, P = .01). The apoptotic eosinophil counts in SAR patients were statistically higher out of pollen season (3.0% +/- 4.5%) than in pollen season (0.38% +/- 0.80%, P = .02) and higher than those of NAR patients (0.14% +/- 0.26%, P = .005). The apoptotic ratio was statistically higher after pollen season compared with pollen season (0.720% +/- 0.394% vs 0.044% +/- 0.116%, P = .002). Blood eosinophil counts of SAR patients were increased during the pollen season (364 +/- 187/mm3) compared with out of season (278 +/- 219/mm3, P = .04) and with NAR patients (85 +/- 54/mm3, P = .001). The number of SAR patients who had BHR during the pollen season (7/14) was higher than the number who had BHR out of season (2/14, chi2 = 4.2, P = .04). CONCLUSION: Our data indicate that changes in eosinophil counts and eosinophil apoptosis may be related to the changes of natural pollen exposure and seasonal changes of BHR in SAR patients.     

Sublingual immunotherapy abrogates seasonal bronchial hyperresponsiveness in children with Parietaria-induced respiratory allergy: a randomized controlled trial

BACKGROUND: The use of immunotherapy in asthmatic children is still controversial. Sublingual immunotherapy (SLIT) may represent an advance, due to the good safety profile, but little is known about its effects on lung function and nonspecific bronchial responsiveness. OBJECTIVE: The aim of this study was to assess the effects of SLIT on these parameters, in children with Parietaria pollen-induced asthma. METHODS: Thirty children with asthma solely due to Parietaria who participated in a previous randomized, placebo-controlled trial with SLIT were studied: pulmonary function test and methacholine challenge were carried out at baseline in winter 1999 (out season), during the 1999 season (before randomization), and during the 2001 season. RESULTS: Before randomization, there was a significant fall in methacholine provocation concentration during the pollen season vs baseline in both groups (SLIT group 9.78 +/- 5.95 mg/ml vs 3.37 +/- 2.99 mg/ml; placebo 8.70 +/- 6.25 mg/ml vs 2.44 +/- 2.25 mg/ml; P =.005). In the second pollen season, the response to methacholine returned to baseline values in the active group (9.10 +/- 7.7 mg/ml; P = NS vs baseline), whereas in the placebo group a significant increase in reactivity was still present (2.46 +/- 2.26; P = 0.008 vs baseline). No significant difference in FEV(1) and FEF(25-75) between the two groups was observed at all times. CONCLUSIONS: Our data show that SLIT abrogates the seasonal bronchial hyperreactivity in children with asthma due to Parietaria. This may be regarded as an indirect evidence of the effect on bronchial inflammation.     

A single nasal allergen challenge increases induced sputum inflammatory markers in non-asthmatic subjects with seasonal allergic rhinitis: correlation with plasma interleukin-5

BACKGROUND: Seasonal allergic rhinitis (SAR) is a risk factor for asthma in affected individuals. Nasal allergic inflammation enhances bone-marrow eosinophil production, mainly via IL-5, and rhinitis patients have increased airway inflammation during the pollen season. OBJECTIVE: To assess the impact of nasal allergy on sputum inflammatory markers. METHODS: In an open-labelled, randomized, placebo-controlled cross-over study with 16 non-asthmatic SAR patients (median age 25 years, 56% males), the effect of a single nasal allergen challenge performed out of season on induced sputum inflammatory parameters was evaluated. SAR patients were identified by history, skin-prick test and specific IgE. All patients had normal lung function/bronchial hyper-responsiveness out of season and a negative asthma/wheezing history. Sputum cells and supernatant levels of ECP, sICAM, IL-5 and IL-10, and plasma levels of IL-5 and ECP, were measured before and 24 h after nasal allergen challenge. After a washout period of at least 4 weeks, the procedure was repeated with placebo challenge (diluent). RESULTS: Nasal allergen challenge led to an increase in sputum ECP (pre = 60 +/- 12, post = 212 +/- 63 micro g/L, P = 0.02 vs. placebo), and sICAM (4.8 +/- 2.7 to 6.5 +/- 2.9 ng/mL, P = 0.02 vs. placebo), whereas IL-10 decreased after provocation (44 +/- 11 to 29 +/- 6 pg/mL, P = 0.06 vs. placebo). Sputum IL-5 was undetectable in all patients. The absolute number of blood and sputum eosinophils did not change significantly after allergen or placebo challenge (P > 0.07, both comparisons). Plasma levels of IL-5 increased after allergen challenge (8.7 +/- 2.9 to 14.5 +/- 3.9 pg/mL, P = 0.001), and the increase in plasma IL-5 was positively correlated with the rise in sputum ECP in a subgroup of 'responders' (n = 12, r = 0.71, P = 0.01). CONCLUSIONS: A single nasal allergen challenge in SAR patients increased markers of allergic inflammation in the lower respiratory tract, possibly via pronounced activation of inflammatory cells through circulating immediate-type reaction cytokines like IL-5. These findings may provide additional explanatory data for the high susceptibility of SAR patients to incident asthma.     

Dissimilarity between seasonal changes in airway responsiveness to adenosine-5'-monophosphate and methacholine in patients with grass pollen allergic rhinitis: relation to induced sputum

BACKGROUND: In patients with allergic rhinitis, bronchial hyperresponsiveness (BHR) and airway inflammation may increase during pollen exposure. BHR can be assessed by adenosine-5'-monophosphate (AMP) or methacholine challenge. It has been suggested that BHR to AMP is more closely related to airway inflammation than BHR to methacholine. Seasonal allergic rhinitis offers a dynamic model to study changes in BHR and airway inflammation during natural allergen exposure. METHODS: We measured BHR [provocative concentration causing a 20% fall (PC(20)) in forced expiratory volume in 1 s (FEV(1))] to AMP and methacholine, and induced sputum cells in 16 rhinitis patients before and during the 2001 grass pollen season. RESULTS: There was a decrease in PC(20) methacholine during pollen exposure (geometric mean PC(20) from 3.22 to 1.73 mg/ml, p = 0.0023), whereas no reduction was observed for PC(20) AMP (p = 0.11). There was no increase in sputum eosinophils [pre: 0.69% (95% confidence interval 0.22-2.07); during: 1.85 (0.55- 5.6), p = 0.31]. Although the correlation of log PC(20) methacholine and log PC(20) AMP at baseline was good (r = 0.76, p = 0.001), individual seasonal changes (doubling concentrations) in PC(20) methacholine were not correlated with changes in PC(20) AMP (rho = 0.21, p = 0.44). There was no correlation between baseline log PC(20) methacholine or seasonal changes in PC(20) methacholine and sputum eosinophils (p > 0.12, all correlations). In contrast, there was a significant correlation between seasonal changes in PC(20) AMP and changes in sputum eosinophils (rho = -0.59, p = 0.025). CONCLUSIONS: These data show dissimilarity between seasonal changes in PC(20) AMP and methacholine in patients with seasonal allergic rhinitis. Moreover, PC(20) AMP seems to be more closely related to sputum eosinophils than PC(20) methacholine. The clinical significance of this discrepancy is unclear.     

Serum ECP levels and methacholine challenge in infants with recurrent wheezing.

BACKGROUND: High levels of serum eosinophil cationic protein (sECP) as a marker of eosinophilic airway inflammation have been described as a predictor of childhood asthma. Bronchial hyperreactivity (BHR) appears to be secondary to the release of inflammatory mediators. OBJECTIVE: We investigated the possible correlation between eosinophilic inflammation and BHR in 72 infants with recurrent wheezing. METHODS: To determine bronchial reactivity, lung function measurements with methacholine challenge were performed in 72 infants, aged 12 to 30 months, and the degree of BHR to methacholine was compared with sECP values. Patients were grouped according to low (group 1, <10 microg/L, n = 22), medium (group 2, 10 to 20 microg/L, n = 23), and high (group 3, >20 microg/L, n = 27) sECP values. RESULTS: In group 1, sECP levels ranged from 3.1 to 9.9 microg/L, mean 6.6 microg/L +/- standard deviation [SD] 2.3, in group 2, from 10.3 to 19.8 microg/L, mean 14.3 microg/L +/- SD 2.8, and in group 3 from 23.0 to 66.7 microg/L, mean 34.5 microg/L +/- SD 9.5. Distribution of provocative methacholine concentration among groups was as follows: group 1, 30 to 976 microg, mean 350.9 microg +/- SD 258.3; group 2, 36 to 752 microg, mean 340.7 microg +/- SD 226.3; group 3, 41 to 848 microg, mean 301.3 microg +/- SD 189.8 methacholine. CONCLUSION: There was no significant correlation between sECP levels and bronchial reactivity in all groups (r = -0.076, P = 0.6), indicating that these parameters reflect two independent pathogenic mechanisms in the etiology of childhood 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.     

Effect of current exposure to Der p 1 on asthma symptoms, airway inflammation, and bronchial hyperresponsiveness in mite-allergic asthmatics

The existence of a dose-response relationship between indoor allergen exposure and sensitization has been widely described, but the effect of allergen exposure on asthma activity (symptoms, bronchial hyperresponsiveness [BHR], and inflammation) is not clear. Our aim was to determine the existence of an association among current exposure to mite allergens and symptoms, BHR, and airway inflammation assessed in blood and sputum from asthmatic patients sensitized to Dermatophagoides pteronyssinus. We selected 31 mild and recently diagnosed (12-24 months) asthma patients sensitized to D. pteronyssinus. Allergenic exposure (Der p 1, Der 2) was assessed by a commercial assay based on monoclonal antibodies (mAb), carried out on the dust samples collected from patients' beds in a standardized way. Patients completed an asthma symptom questionnaire and underwent skin tests, methacholine bronchial challenge, and sputum induction. Sputum cell profile was analyzed and eosinophil cationic protein (ECP), tryptase, albumin, and interleukin(IL)-5 levels were quantified in sputum supernatant. Total eosinophil numbers and ECP levels were measured in blood samples. Most patients were exposed to Der p 1 levels under 2 microg/g of dust. Der p 1 exposure was higher among the subjects with positive sputum tryptase detection (P = 0.020). Der p 1 levels showed a trend toward correlation with asthma symptoms (P = 0.066, r = 0.36) and correlated with sputum tryptase levels (P = 0.032, r = 0.42). No relationship between BHR, eosinophilic inflammation, and allergenic exposure was found. Our results suggest that asthma symptoms and lung mast-cell activation are at least partially dependent on current allergen exposure. The lack of correlation between mite exposure, eosinophilic inflammation, and BHR supports the role of other factors that enhance the immunologic response initiated by allergen, increasing the activity of asthma.     

Airway neutrophil inflammation in nonasthmatic patients with food allergy

BACKGROUND: Patients with food allergy (FA) have been recently shown to develop bronchial hyperresponsiveness (BHR), despite the absence of any concomitant asthmatic manifestation. In order to explain this observation, we sought to examine the presence of a bronchial inflammation in induced sputum of nonasthmatic patients with FA. METHODS: Twelve nonasthmatic patients with FA (urticaria, digestive symptoms, anaphylaxis) were included in the study. Results were compared to these obtained from eight asthmatic patients without food allergy and eight healthy controls. Diagnosis of FA was based on double-blind placebo-controlled challenge. Sputum cells and fluid-phase eosinophil cationic protein (ECP), myeloperoxidase (MPO) and interleukin-8 (IL-8) were measured in induced sputum. BHR was evaluated using methacholine inhalation. RESULTS: Sputum from asthmatics, in comparison with the sputum of healthy subjects and patients with FA contained a higher proportion of eosinophils and higher levels of ECP (< 0.001). In marked contrast, patients with FA exhibited an increased proportion of neutrophils and IL-8 in comparison with asthmatics and controls (P < 0.05 for neutrophils and P < 0.001 for IL-8). There was a significant correlation between sputum neutrophils and IL-8 (r = 0.68, P < 0.001). MPO levels were not different between the groups. There was a trend toward higher levels of IL-8 and ECP in food allergic patients with BHR in comparison with patients with FA without BHR. CONCLUSION: Our results demonstrate that a subclinical neutrophil airway inflammation is present in patients with food allergy free of clinical respiratory symptoms and that IL-8 may be an important mediator of this neutrophilia.     

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.     

Cysteinyl-leukotriene levels in sputum differentiate asthma from rhinitis patients with or without bronchial hyperresponsiveness

BACKGROUND: We have previously reported that asthma differs from rhinitis with or without bronchial hyperresponsiveness in the perception and degree of lower airway inflammation. OBJECTIVE: The aim of the present study was to investigate whether sputum levels of inflammatory markers could further distinguish these patient groups. METHODS: Patients with seasonal allergic rhinitis with or without asthma or bronchial hyperresponsiveness to methacholine were investigated. Induced sputum was performed during as well as off season, and analysed for cysteinyl-leukotrienes, hyaluronan, eosinophilic cationic protein (ECP) and other inflammatory markers. RESULTS: Asthmatic patients differentiated from those with rhinitis with or without bronchial hyperresponsiveness in levels of cysteinyl-leukotrienes [geometric mean: 3.3 (lower 95%-upper 95% confidence interval (CI) of geometric mean: 1.9-5.1) vs. 1.4 (0.9-2.2) and 0.7 (0.3-1.6) pg/microg total protein] and hyaluronan [0.30 (0.22-0.43) vs. 0.15 (0.10-0.20) and 0.20 (0.12-0.35) ng/microg total protein] in sputum. The levels of cysteinyl-leukotrienes decreased in sputum from the asthmatic patients, while the levels of hyaluronan remained elevated off-season. Furthermore, elevated levels of ECP were noticed among both the asthmatic and rhinitis patients with hyperresponsiveness compared with controls [0.022 (0.014-0.033) and 0.015 (0.011-0.021) compared with 0.010 (0.007-0.014) ng/microg total protein]. The level of ECP remained elevated off season. CONCLUSION: Cysteinyl-leukotrienes are possibly more related to mast cell-mediated inflammation and remodelling, also indicated by increased levels of hyaluronan during and off season. This inflammation may be partly different from the eosinophil-driven inflammation.     

Effect of anti-immunoglobulin E on nasal inflammation in patients with seasonal allergic rhinoconjunctivitis

BACKGROUND: Binding of allergens to IgE on mast cells and basophils causes release of inflammatory mediators in nasal secretions. OBJECTIVE: The combined effect of specific immunotherapy (SIT) and omalizumab, a humanized monoclonal anti-IgE antibody, on release of eosinophilic cationic protein (ECP), tryptase, IL-6, and IL-8 in nasal secretion was evaluated. METHODS: Two hundred and twenty five children (aged 6-17 years) with a history of seasonal allergic rhinoconjunctivitis induced by birch and grass pollen were randomized into four groups: either birch- or grass-pollen SIT in combination with either anti-IgE or placebo. Complete sets of nasal secretion samples before treatment Visit 1 (V1), during birch- (V2) and grass (V3)-pollen season and after the pollen season (V4) were collected from 53 patients. RESULTS: A significant reduction in tryptase only was seen in the anti-IgE-treated group at V2 (P<0.05) and V4 (P<0.05) compared with the placebo group. During the pollen season, patients with placebo showed an increase of ECP compared with baseline (V2: +30.3 microg/L; V3: +134.2 microg/L, P< 0.005; V4: +79.0 microg/L, P< 0.05), and stable levels of tryptase, IL-6 and IL-8. Treatment with anti-IgE resulted in stable ECP values and a significant decrease of tryptase compared with V1 (baseline): V2: -80.0 microg/L (P< 0.05); V3: -56.3 microg/L, which persisted after the pollen season with V4: -71.6 microg/L (P< 0.05). After the pollen season, a decrease of IL-6 was observed in both groups (V4 placebo group: -37.5 ng/L; V4 anti-IgE group: -42.9 ng/L, P< 0.01). CONCLUSION: The combination of SIT and anti-IgE is associated with prevention of nasal ECP increase and decreased tryptase levels in nasal secretions.     

Bronchial eosinophilic infiltration in Crohn's disease in the absence of pulmonary disease

BACKGROUND: Immunological and functional bronchopulmonary abnormalities may be present in up to two-thirds of patients with Crohn's disease. Having recently described a mild increase in methacholine airways responsiveness in these patients, we investigated whether this physiological abnormality is associated with bronchial inflammation since it has previously been described in asthma. METHODS: Eighteen patients with Crohn's disease and 15 healthy controls matched for age, atopy and smoking habit, were studied. All the subjects underwent a bronchial methacholine challenge (1, 4 and 16 mg/mL) and a sputum induction by inhalation of hypertonic saline (NaCl 4.5%). The sputum samples were analysed for their cellular composition as well as for the levels of several mediators and proteins in the fluid phase, including eosinophil cationic protein (ECP), myeloperoxydase, albumin, alpha2-macroglobulin, interleukin-8 (IL-8), IgA and IL-8/immunoglobulin A complexes. RESULTS: When compared to control subjects, patients with Crohn's disease had significantly higher sputum eosinophil counts (14.5% [0-79.9%] vs 0.2% [0-2.3%]; P < 0. 001) and ECP levels (26.2 microg/L [4-124.2 microg/L] vs 9.8 microg/L [0-94.2 microg/L]; P < 0.05). However, patients with Crohn's disease had no sign of increased plasma exudation as reflected by sputum levels of albumin and alpha2-macroglobulin similar to those seen in control subjects. Furthermore the sputum levels of IL-8, IgA and IL-8/IgA complexes were not significantly different between the two groups. The magnitude of the fall in forced expiratory volume in 1 s after methacholine inhalation was significantly increased in Crohn's disease patients although it did not correlate with the extent of sputum eosinophilia or with the sputum ECP levels. CONCLUSIONS: Crohn's disease patients without any clinical respiratory involvement have airway eosinophilia without local increased plasma exudation. However, bronchial eosinophilia in Crohn's disease per se is not sufficient to induce clinically significant airway hyperresponsiveness, suggesting that other factors than bronchial eosinophilic infiltration are required for the clinical expression of an airway instability.     

Nitric oxide metabolites in induced sputum: a marker of airway inflammation in asthmatic subjects

BACKGROUND AND OBJECTIVE: The role of nitric oxide (NO) needs to be further clarified in allergic inflammation. This study was designed to investigate the relationships between NO metabolites and eosinophil count, eosinophil cationic protein (ECP), interleukin (IL)-5 in induced sputum from asthmatics. METHODS: Hypertonic saline-induced sputum was obtained in 25 asthmatic subjects, among which 13 patients were examined before and after anti-asthmatic medications including steroid preparations. Ten normal subjects were enrolled as controls. Fresh expectorated sputum separated from saliva was treated with equal volume of dithiothreitol 0.1%, cytospinned for cell count, and the supernatant was collected for biochemical assay. NO metabolites were assayed by using modified Griess reaction. ECP was measured by fluoroimmunoassay, and detected IL-5 by a sandwich ELISA. RESULTS: Asthmatic subjects, compared with controls, had significantly higher concentration of NO metabolites (1035.4 +/- 125.3 vs 557.2 +/- 101.5 micromol/L, P < 0.01), higher percentage of eosinophils (25.6 +/- 4.6 vs 1.7 +/- 0.2%, P < 0.01), and higher levels of ECP (1117.8 +/- 213.9 vs 154.6 +/- 47.4 microg/L, P < 0.01) in the induced sputum. IL-5 was detected more frequently in asthmatic subjects than in control subjects (11/25 [44%] vs 1/10 [10%], P < 0.05). According to asthma severity, moderate to severe asthmatic subjects (n = 18) had higher level of NO metabolites (1143.8 +/- 156.3 vs 575.5 +/- 89.5 micromol/L, P < 0. 01), higher levels of ECP and IL-5 (P < 0.01, respectively) in the induced sputum than in those of mild asthmatic subjects (n = 7). NO metabolites, the percentage of eosinophils, the levels of ECP, and IL-5 were reduced following treatment with anti-asthmatic drugs (P < 0.01, respectively). There were significant positive correlations between NO metabolites and percentage of eosinophils or ECP (r = 0. 34, P < 0.05; r = 0.28, P < 0.05). Negative correlations were noted between FEV1, FEV1/FVC and proportion of eosinophils, ECP, or IL-5 levels. CONCLUSION: These findings confirmed that the level of NO metabolites was increased in the tracheobronchial secretion of asthmatic subjects and was paralleled with severity of asthma. Measurement of NO metabolites in induced sputum may be used for monitoring the degree of airway inflammation in asthmatics.     

Effect of immunotherapy on asthma progression, BHR and sputum eosinophils in allergic rhinitis

BACKGROUND: Bronchial hyperresponsiveness (BHR) and airway inflammation are frequently associated with allergic rhinitis, and may be important risk factors for the development of asthma. Specific immunotherapy (SIT) reduces symptom in subjects with allergic rhinitis, but the mechanisms are not clear. AIMS OF THE STUDY: To assess the effect of Parietaria-SIT on asthma progression, rhinitic symptoms, BHR, and eosinophilic inflammation. METHODS: Nonasthmatic subjects with seasonal rhinitis were randomly assigned to receive Parietaria pollen vaccine (n = 15) or matched placebo (n = 15). Data on symptoms and medication score, BHR to methacholine, eosinophilia in sputum were collected throughout the 3-year study. RESULTS: By the end of the study, in the placebo group, symptoms and medication scores significantly increased by a median (interquartile range) of 121% (15-280) and 263% (0-4400) respectively (P < 0.01), whereas no significant difference was observed in the SIT group. We found no significant changes in sputum eosinophils and BHR to methacholine in both groups throughout the study. Nine of 29 participants developed asthma symptoms during the study; of these, only two subjects (14%) in the SIT-treated group (P = 0.056). CONCLUSIONS: Parietaria-SIT reduces symptom and rescue medication scores, but no changes in BHR to methacholine or sputum eosinophilia were observed. Moreover, Parietaria-SIT appears to prevent the natural progression of allergic rhinitis to asthma, suggesting that SIT should be considered earlier in the management of subjects with allergic rhinitis.     

Low levels of CC16 in nasal fluid of children with birch pollen-induced rhinitis

BACKGROUND: Clara cell protein 16 (CC16; secretoglobin 1A1) is an anti-inflammatory protein mainly expressed in the epithelial cells in the airways. OBJECTIVE: To compare the levels of CC16 in nasal lavage (NAL) from children with intermittent allergic rhinitis and healthy controls and to study the effect of a local steroid. METHODS: Thirty schoolchildren with birch pollen allergy and 30 healthy controls from the same schools were included in the study. The NAL fluid was collected before the season, during the birch pollen season and, for the patients, after 1 week of treatment with a local steroid. Symptom scores were obtained on every occasion. CC16 and eosinophil cationic protein (ECP) were analyzed with enzyme-linked immunosorbent assay. RESULTS: The nasal fluid levels of CC16 were significantly lower in patients than in controls, before and during pollen season. Before the season, the median CC16 concentrations were 9.1 (range 1.1-117) microg/l in patients and 25.7 (6.1-110.2) microg/l in controls. During the season, the median CC16 concentrations in nasal fluid were 12.9 (2.3-89.7) microg/l in the allergic children and 22.0 (9.5-90.1) microg/l in the healthy controls (P = 0.0005). Symptom scores, nasal fluid eosinophils and ECP were higher in patients during the season. Treatment with a local steroid did not change the CC16 levels. CONCLUSIONS: Nasal fluid CC16 levels were lower in children with birch pollen-induced allergic rhinitis than in healthy controls both before and during the pollen season. We speculate that reduction in anti-inflammatory activity by CC16 may contribute to the pathogenesis of allergic rhinitis.     

Increased eosinophil cation protein level in sensitized nonasthmatics is linked to subsequent hyperresponsiveness to methacholine. The Odense Schoolchild Study

Background: Increased levels of eosinophil cation protein (ECP) in sensitized subjects may reflect early stages of an ongoing inflammatory process and therefore precede asthma and bronchial hyperreactivity. Aim: To study whether nonasthmatic subjects with sensitization to allergens and increased ECP levels are at a higher risk for subsequent increased bronchial reactivity compared with sensitized nonasthmatics with normal ECP levels. Methods: A prospective study of 240 schoolchildren with a mean age of 13.9 years (range: 12.6-15.9) who were followed up after 6.3 years. Bronchial reactivity was assessed by methacholine provocation testing. Sensitization was defined by one or more positive reactions (>3 mm wheal) to 10 common aeroallergens by skin prick testing. Increased ECP was defined as values above 20 microg/l. This separated the subjects into four categories: group 1: healthy controls without sensitization (n = 147); group 2: sensitized subjects with a serum ECP below 20 microg/l (n = 55); group 3: sensitized subjects with an ECP level at or above 20 microg/l (n = 16), and group 4: all asthmatics (n = 22). Results: Bronchial reactivity was similar in subjects of groups 2 and 3 at baseline (p = 0.8). Six years later, subjects from group 3 were more responsive to methacholine compared with subjects from group 2 (median: 12.7 versus 20.5 micromol; p < 0.05). In a logistic regression with hyperresponsiveness to methacholine at follow-up as dependent variable, the odds ratios (OR) for the groups were, with group 1 as reference: group 2: OR = 2.2 (0.8-6.6: p = 0.2), group 3: 5.9 (1. 6-21.7: p < 0.01). Conclusion: Subjects with sensitization and increased ECP levels are subsequently more airway-responsive to methacholine compared with sensitized subjects with normal ECP levels. This supports the hypothesis that sensitization is linked to increased bronchial reactivity through a process in which markers of inflammation are involved.     

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.     

Monitoring of seasonal variability in bronchial hyper-responsiveness and sputum cell counts in non-asthmatic subjects with rhinitis and effect of specific immunotherapy

Bronchial hyper-responsiveness (BHR) is documented in a proportion of non-asthmatic individuals with allergic rhinitis (NAAR) and reflects inflammatory events in the lower airways. Natural exposure to allergens is known to modulate BHR and the level of airway inflammation in asthma, but less consistently in NAAR. Specific immunotherapy (SIT) attenuates symptoms possibly by reducing BHR and airway inflammation. The influence of natural exposure to Parietaria pollen on BHR and sputum cell counts of NAAR was investigated and the effect of Parietaria SIT examined. Thirty NAAR, monosensitized to Parietaria judaica, participated in a randomized, double-blind, placebo-controlled, parallel group study of the effects of a Parietaria pollen vaccine on symptoms/medication score, BHR to inhaled methacholine and adenosine 5'-monophosphate (AMP), and cell counts in the sputum collected out of and during the pollen seasons for 36 months. Seasonal variation in BHR to inhaled methacholine and AMP and changes in sputum cell counts were documented. Changes were consistent for AMP, but not methacholine, and invariably associated with modifications in sputum eosinophils and epithelial cells. The clinical efficacy of Parietaria SIT was associated with a decline in the seasonal deterioration of BHR to AMP, whereas no significant effect was observed on BHR to methacholine or sputum cell differentials. Between-groups comparison of the seasonal changes in PC15 methacholine values and sputum cell differentials calculated as the AUC were not statistically significant, whereas a significant difference in PC15 AMP was demonstrated throughout the study (P=0.029), the median (inter-quartile range) AUC values being 2478.5 (1153.3-3600.0) and 1545.5 (755.3-1797.9) for the SIT- and placebo-treated group, respectively. Bronchial airways of NAAR exhibit features of active inflammation that deteriorate during natural allergen exposure, particularly with regard to BHR to AMP. The clinical efficacy of Parietaria SIT was exclusively associated with attenuation in seasonal worsening of PC15 AMP, suggesting that AMP may be useful in monitoring changes in allergic inflammation of the airways.     

Effect of cetirizine on bronchial hyperresponsiveness in patients with seasonal allergic rhinitis and asthma

Although H1 antihistamine compounds (H1) are highly effective in the treatment of allergic rhinitis (AR), their role in the treatment of asthma is still controversial. Because a strong association between AR and bronchial hyperresponsiveness (BHR) has been reported, this study was designed to assess the effect of a new H1 anti histamine, cetirizine (C), on nonspecific BHR in patients with AR. Twelve patients were included in a double-blind, crossover, placebo-controlled trial. All patients had positive skin tests for common allergens and showed BHR to inhaled methacholine after specific nasal allergenic challenge. After a washout period of 1 week to ensure the stability of the BHR, the patients received, by crossover randomization, C 10 mg daily or placebo (P) for 2 weeks. After each treatment period, BHR and nasal blocking index (NBI) were measured 1 and 6 h after nasal challenge. Bronchial responsiveness was expressed as methacholine PD20, the provocation dose of methacholine causing a 20% decrease in FEV1. Measurements were then performed after 2 weeks of C and after 2 weeks of P. Baseline values of PD20 (median) measured before challenge showed no difference after cetirizine or after placebo (1.36 mg). Results 1 h after allergen did not show significant differences between C (methacholine PD20=0.522 mg) and placebo (methacholine PD20=0.455 mg). By contrast, 6 h after challenge, methacholine PD20 was 0.918 mg for C and 0.483 mg for P (P=0.042). Similarly, NBI showed no change between C and P 1 h after challenge, whereas the difference was significant 6 h after challenge (P=0.011 ). These data demonstrate a protective nasal effect of C against BHR measured 6 h after nasal allergen challenge in patients with AR. They suggest that C may be useful in patients with asthma associated with AR.     

Comparison of allergen-induced changes in bronchial hyperresponsiveness and airway inflammation between mildly allergic asthma patients and allergic rhinitis patients

Bronchial eosinophilic inflammation and bronchial hyperresponsiveness (BHR) are the main features of allergic asthma (AA), but they have also been demonstrated in allergic rhinitis (AR), suggesting a continuity between both diseases. In spite of not fully reproducing natural allergenic exposure, the allergen bronchial provocation test (A-BPT) has provided important knowledge of the pathophysiology of AA. Our aim was to verify the existence of a behavior of AA and AR airways different from the allergen bronchial challenge-induced airway eosinophilic inflammation and BHR changes. We studied a group of 31 mild and short-evolution AA and 15 AR patients, sensitized to Dermatophagoides pteronyssinus. The A-BPT was performed with a partially biologically standardized D. pteronyssinus extract, and known quantities of Der p 1 were inhaled. Peripheral blood (eosinophils and ECP) and induced sputum (percentage cell counts, ECP, albumin, tryptase, and interleukin [IL]-5) were analyzed, before and 24 h after A-BPT. Methacholine BHR, assessed before and 32 h after the A-BPT, was defined by M-PD20 values and, when possible, by maximal response plateau (MRP). The A-BPT was well tolerated by all the patients. AA presented a lower Der p 1 PD20 and a higher occurrence of late-phase responses (LPR). M-PD20 values decreased in AA, but not in AR, patients. MRP values increased in both groups. Eosinophils numbers and ECP levels increased in blood and sputum from both AA and AR, but only the absolute increment of sputum ECP levels was higher in AA than AR patients (P = 0.025). The A-BPT induced no change in sputum albumin, tryptase, or IL-5 values. We conclude as follows: 1) In spite of presenting a lower degree of bronchial sensitivity to allergen, AR patients responded to allergen inhalation with an eosinophilic inflammation enhancement very similar to that observed among AA. 2) MRP levels increased in both AA and AR patients after allergen challenge; however, M-PD20 values significantly changed only in the AA group, suggesting that the components of the airway response to methacholine were controlled by different mechanisms. 3) It is possible that the differences between AR and AA lie only in the quantitative bronchial response to allergen inhalation.