Effect of inhaled glucocorticoids on IL-1 beta and IL-1 receptor antagonist (IL-1 ra) expression in asthmatic bronchial epithelium.

BACKGROUND: Accumulating evidence suggests that the cytokine network is central to the immunopathology of bronchial asthma and the existence of naturally occurring cytokine antagonists has added to this complexity. Upregulation of both interleukin 1 beta (IL-1 beta) and its naturally occurring receptor antagonist, interleukin 1 receptor antagonist (IL-1ra), has previously been observed on asthmatic bronchial epithelium compared with normal airways. METHODS: The effect of inhaled beclomethasone dipropionate (BDP) on asthmatic bronchial epithelial expression of IL-1 beta and IL-1ra was studied. Frozen bronchial biopsy specimens from nine asthmatic subjects receiving 1000 micrograms BDP daily for eight weeks and from six asthmatic subjects receiving matching placebo were stained with anti-IL-1 beta and anti-IL-1ra antibodies. Hue-saturation-intensity (HSI) colour image analysis was used to quantify the brown immunoperoxidase reaction colour present on the bronchial epithelium. RESULTS: There was a significant twofold decrease in the epithelial expression of IL-1 beta after treatment with BDP but no significant change was seen in IL-1ra (P = 0.175). CONCLUSION: The selective inhibition of IL-1 beta, without effect on IL-1ra, provides a novel mechanism for the anti-inflammatory action of glucocorticosteroids.

Bronchial inflammation and the common cold: a comparison of atopic and non-atopic individuals.

BACKGROUND: Cold virus infections are associated with asthma attacks and with increased bronchial responsiveness even in normal subjects. Possible mechanisms include epithelial damage, interaction with adhesion molecules or with T-helper cell subsets. OBJECTIVE: To determine whether colds increase lower airway inflammation, comparing atopic with non-atopic normal subjects. METHODS: Thirty healthy volunteers (15 atopic) took part. Baseline tests included viral serology, microbiological culture and polymerase chain reaction for rhinovirus infection (HRV-PCR), histamine bronchial provocation and bronchoscopy. Twenty subjects (eight atopic) underwent repeat tests when they developed a cold. RESULTS: Forced expiratory volume in one second (FEV1) was significantly lower during colds (-0.19 L [95% confidence interval -0.10, -0.29], P = 0.0004) and there was a significant increase in bronchial responsiveness (+0.62 doublings of the dose-response slope [+0.24, +1.00], P = 0.003). Eight subjects (two atopic) had a diagnosed viral infection: two HRV, three coronavirus (HCV), one HRV + HCV, one parainfluenza III (PI) and one respiratory syncytial virus (RSV) (also Haemophilus influenzae). In biopsies, during colds, total eosinophils (EGI+) increased significantly (geometric mean 6.73-fold [1.12,40.46], P = 0.04). Activated eosinophils (EG2+) only increased significantly in the subgroup without diagnosed viral infection and particularly in atopic rhinitics. T-suppressor (CD8+) cells also increased significantly (median + 178.3 cells mm2, P = 0.004). Epithelial expression of intercellular adhesion molecule-1 (ICAM-1) expression increased in four atopic rhinitics during colds. Bronchial washings showed a significant increase in neutrophils (GM 1.53-fold [1.04,2.25], P = 0.02). CONCLUSION: Lower airway inflammation was present in atopic and non-atopic normal subjects with colds. Atopic subjects differed in that they were less likely to have positive virological tests and were more likely to show activated eosinophilia in the lower airway, despite a similar spectrum of symptoms.

Regular albuterol, nedocromil sodium, and bronchial inflammation in asthma.

Adult, nonsmoking patients with mild to moderate asthma were randomized to receive 4 mg nedocromil sodium (n = 13), 200 micrograms albuterol (n = 13), or placebo (n = 12) four times daily for 16 wk in a double-blind, double-dummy protocol. Before and after treatment, patients underwent histamine bronchial provocation, followed by fiberoptic bronchoscopy. Bronchial mucosal biopsy tissue and bronchoalveolar lavage fluid were examined in detail. Daily diary cards were kept by each patient. Compared with baseline, the numbers of total (EG1) and activated (EG2) eosinophils, expressed as cells per square millimeter of bronchial biopsy tissue, decreased after treatment with nedocromil sodium (pretreatment: EG1 = 152.2 +/- 42.5 and EG2 = 143.8 +/- 36.8; post-treatment: EG1 = 115.4 +/- 35.1 and EG2 = 104.9 +/- 31.6) and increased after treatment with albuterol (pretreatment: EG1 = 129.3 +/- 28.0 and EG2 = 127.5 +/- 30.2; post-treatment: EG1 = 238.0 +/- 55.0 and EG2 = 211.4 +/- 50.4). Although the changes between the active treatment groups were significantly different (p < 0.05), no such significant differences were found in eosinophil numbers before and after treatment when comparisons were made between either of the active treatment groups and the placebo group. Although not significant, the changes in concentration of eosinophil cationic protein in bronchoalveolar lavage reflected the changes seen in numbers of activated eosinophils. No treatment differences were detected for mast cell or lymphocyte numbers. There were no statistical differences between treatment groups for clinical findings, with the exception of evening peak flow, which was significantly increased (p < 0.05) in the albuterol group.(ABSTRACT TRUNCATED AT 250 WORDS)

Effect of nitrogen dioxide and sulphur dioxide on airway response of mild asthmatic patients to allergen inhalation.

Air pollution may enhance the airway response of asthmatic subjects to allergen inhalation. To test the hypothesis that sulphur dioxide and nitrogen dioxide alone or in combination could have a contributory role, we have studied the effect of 6 h exposure to air, 200 parts per billion (ppb) sulphur dioxide, 400 ppb nitrogen dioxide, and the two gases together on the airway response to inhaled allergen in ten volunteers with mild atopic asthma. The subjects were exposed to the gases in random order at weekly visits, then challenged with pre-determined concentrations of Dermatophagoides pteronyssinus allergen 10 min after each exposure. The forced expiratory volume in 1 s (FEV1), forced vital capacity (FVC), and cumulative breath units (CBU) of D pteronyssinus allergen required to produce a 20% fall in FEV1 (PD20FEV1) were measured after each exposure. Compared with air, neither sulphur dioxide nor nitrogen dioxide nor the combination significantly altered FEV1 or FVC. Although the decreases in PD20FEV1 after exposure to each agent alone were not significant (41.2%, p = 0.125 after nitrogen dioxide; 32.2%, p = 0.506 after sulphur dioxide) the decrease after exposure to the combination was significant (60.5 [SE 8.1]%, p = 0.015). Exposure to a combination of sulphur dioxide and nitrogen dioxide in concentrations that could be encountered in heavy traffic enhances the airway response to inhaled allergen, possibly as a result of previous airway inflammation.

Effect of inhaled beclomethasone dipropionate on expression of proinflammatory cytokines and activated eosinophils in the bronchial epithelium of patients with mild asthma.

Increasing evidence suggests that cytokines play a role in airway inflammation by attracting and activating inflammatory cells. This may lead to epithelial cell damage and airway hyperresponsiveness. Bronchial provocative concentration of histamine causing a 20% fall in forced expiratory volume in 1 second was measured in patients with mild asthma, and bronchial biopsy specimens were stained for granulocyte-macrophage colony-stimulating factor (GM-CSF), interleukin (IL)-8, and activated eosinophils (EG2) in the bronchial epithelium. The effect of inhaled beclomethasone dipropionate was also assessed in a placebo-controlled double-blind manner. There was a correlation between GM-CSF expression and EG2-staining cells (r = 0.484 p < 0.05) in the epithelium. Provocative concentration of histamine causing a 20% fall in forced expiratory volume in 1 second was correlated with GM-CSF expression (r = -0.462, p < 0.05). Treatment with inhaled beclomethasone dipropionate 500 micrograms twice a day led to a significant decrease in both the expression of GM-CSF (p < 0.01) and IL-8 (p < 0.02) and the number of EG2-staining cells (p < 0.01) in the epithelium. The changes in GM-CSF (r = 0.798, p < 0.01) and IL-8 (r = 0.653, p < 0.02) expression were correlated with the changes in EG2-staining cells after treatment. These results suggest that GM-CSF may influence eosinophil activation in the epithelium in vivo and participate in the etiology of bronchial hyperresponsiveness in mild asthma. Also, beclomethasone dipropionate may inhibit eosinophil activation partly by downregulating the expression of GM-CSF and IL-8 in the bronchial epithelium.

Comparison of a new antihistaminic and antiallergic compound KW 4679 with terfenadine and placebo on skin and nasal provocation in atopic individuals.

The effects of three oral doses of a new compound KW 4679 thought to have both antihistaminic and antiallergic properties were compared with terfenadine and placebo in a double-blind cross-over trial in 15 volunteers with seasonal allergic rhinitis. Comparison of the effect of the treatments with either 2.5, 5 or 10 mg b.i.d. of KW 4679, 60 mg b.i.d. of terfenadine or placebo was made on the response to histamine and grass pollen skin-prick testing. Nasal provocation testing with grass pollen was performed on the eighth day of treatment. Nasal airway resistance (NAR) was measured using active posterior rhinomanometry and the dose of grass pollen which caused a 200% increase in NAR was determined. The number of sneezes in the first 12 min was counted. Compared with placebo all doses of KW 4679 and terfenadine significantly inhibited the skin weal response to histamine and grass pollen (P < 0.001). The inhibitory effect of KW 4679 on both histamine and allergen induced skin weals was significantly greater than that of terfenadine (P = 0.001 and P = 0.049 respectively). The results of nasal challenges with grass pollen showed that all doses of KW 4679 and terfenadine were effective in reducing sneeze counts (P < 0.001), though there were no significant effects on allergen induced increase in NAR. All three doses of KW 4679 were generally well tolerated. Drowsiness was reported by some of the volunteers on KW 4679 and one volunteer reported drowsiness whilst taking placebo. Slight and reversible rises in AST and ALT concentrations were observed; these were not considered clinically significant.

The expression of intercellular adhesion molecule-1 and the beta 1-integrins in asthma.

Expression of intercellular adhesion molecule-1 (ICAM-1) appears to be important to the development of bronchial hyperresponsiveness and eosinophilia in Ascaris sensitized monkeys. Beta 1-integrins are expressed on epithelial cells, and may contribute to adherence of epithelial cells to the basement membrane. The aim of this study was to determine whether adhesion receptor expression was altered in human asthmatic bronchial epithelium. Using monoclonal antibody staining, we have examined the expression of ICAM-1 and the alpha 1-alpha 6-subunits of the beta 1-integrin family in bronchial mucosal biopsies from 33 asthmatic and 13 nonasthmatic subjects. The epithelium was positive for ICAM-1 in 26 out of 33 asthmatics, although negative in all 13 nonasthmatics. ICAM-1 expression was not associated with bronchial responsiveness or with medication requirements. Beta 1-integrin staining showed that alpha 2-, alpha 3- and alpha 6-subunits stained the epithelium in all cases. Alpha 4 staining was weakly positive in the epithelium in five asthmatics. Alpha 5 staining was weak in asthmatics and normals. Alpha 4 and alpha 6-subunits also stained inflammatory cells. Epithelial upregulation of ICAM-1 is present in asthma. Beta 1-integrins with alpha 2-, alpha 3- and alpha 6-subunits appear to be constitutively expressed in bronchial epithelium.

Placebo-controlled immunopathologic study of four months of inhaled corticosteroids in asthma.

The effect of prolonged inhaled corticosteroid treatment on bronchial immunopathology was assessed in 25 nonsmoking mildly asthmatic subjects previously receiving intermittent inhaled beta 2-agonist alone. Inhaled beclomethasone dipropionate (BDP), 500 micrograms twice per day or placebo was administered for 4 mo in a double-blind parallel group study. Histamine bronchial provocation, fiberoptic bronchoscopic biopsy, and bronchoalveolar lavage (BAL) were performed before and after treatment. There was no difference in bronchial responsiveness or lung function between groups. In patients treated with BDP compared with placebo, there was a significant reduction in toluidine blue-staining mast cells (p = 0.028) and total (p = 0.005) and activated eosinophils (p = 0.05) in biopsies but no difference in eosinophils or eosinophil cationic protein in BAL. Granulocyte-macrophage colony-stimulating factor expression was significantly reduced in the bronchial epithelium, and the thickness of Type III collagen deposition in the bronchial lamina reticularis reduced from 29.7 +/- 4.4 to 19.8 +/- 3.4 microns (mean +/- 95% confidence interval) (p = 0.04). No change in helper or activated helper T cells occurred. Prolonged BDP treatment reduces inflammatory infiltration, proinflammatory cytokine expression, and subepithelial collagen deposition, a recognized abnormality in asthma.

Factors affecting the long-term variability of bronchial responsiveness in an adult general practice population.

There have been few longitudinal studies of bronchial responsiveness. We wanted to assess the long-term variability and associations of bronchial responsiveness in the general population. Spirometry, bronchial provocation tests, skin-prick tests for allergy, and respiratory symptom questionnaires were repeated every 4 months, for 2 years (August 1987-August 1989), in 122 volunteers recruited from a cross-sectional survey of population. Provocation dose producing a 20% fall in forced expiratory volume in one second (PD20FEV1) and dose-response slope (SL), which gives values for methacholine responsiveness, were measured in all subjects. SL correlated well with PD20FEV1 but repeatability was impaired in those subjects with unmeasurably high PD20FEV1. The 95% range for repeatability of PD20FEV1 was +/- 3.11 doubling doses and +/- 4.52 doubling slopes for SL. Bronchial responsiveness increased in those with self-reported colds and reduced FEV1 in winter 1987-1988, and in males in winter 1988-1989. Bronchial responsiveness increased during the summer (June-August) of both years, significantly in year 1. We conclude that bronchial responsiveness showed minor seasonal variability and that colds were the strongest predictors of increased bronchial responsiveness over the 2 yr period.

Lymphocyte infiltration and thickness of the nasal mucous membrane in perennial and seasonal allergic rhinitis.

We have used immunocytochemical techniques to study infiltration by lymphocytes in biopsy specimens of the nasal mucosal membrane in 24 atopic patients and 10 normal volunteers. Twelve patients had perennial rhinitis and 12 had seasonal allergic rhinitis (SR) to grass pollen. Biopsy specimens were taken both in and out of the pollen season in patients with SR. Biopsy specimens were strained with the indirect immunoperoxidase technique and monoclonal antibodies to CD3, CD4, CD8, CD22, and CD25. T helper cells (CD4+) and CD24+ cells were significantly more numerous in patients exposed to allergen (those with perennial rhinitis and SR in season) compared with normal volunteers, whereas values for SR out of season were intermediate. The thickness of the nasal epithelium was significantly (p < 0.05) greater in biopsy specimens from patients with perennial rhinitis (mean, 51.43 microns) than in those from patients with SR in season (median, 32.44 microns). These results suggest that in allergic rhinitis, natural exposure to allergen is accompanied by increased infiltration of the nasal mucous membrane by T-helper and CD25+ cells.

Comparison of methotrexate 30 mg per week with placebo in chronic steroid-dependent asthma: a 12-week double-blind, cross-over study.

Methotrexate has been shown to have a steroid-sparing effect in chronic steroid-dependent asthmatics at a dose of 15 mg week-1. The aim of this study was to investigate the steroid-sparing activity and adverse events profile of methotrexate 30 mg week-1 in severe steroid-dependent asthma. Eighteen patients who had required 10-50 mg week-1 prednisolone for at least 6 months were asked to participate in a randomized, double-blind, placebo-controlled cross-over study lasting 24 weeks. Daily diary cards of symptoms, peak expiratory flow rate and medication requirements were kept and the patients attended for a chest X-ray, spirometry, lung volumes and gas transfer at commencement and after each 12-week treatment period. Every 3 weeks, adverse events were noted and blood taken for full blood count, urea and electrolytes and liver function tests. Twelve patients completed the trial. Withdrawals were due to non-compliance in two patients, pneumonia in two patients, depression in one patient (on placebo) and severe nausea in one patient. Adverse events were common, probably as a consequence of the higher dosage. Prednisolone requirements were not significantly reduced on methotrexate. Lung function improved on methotrexate with a significant rise in maximal mid-expiratory flow rate and a trend towards improvement in FEV1.

The effect of salbutamol controlled release on airways responsiveness to inhaled methacholine in mild asthmatic subjects.

Single doses of inhaled bronchodilating agents have been shown to reduce airways responsiveness (AR) in both normal and asthmatic individuals. The longer term effects of these treatments on airways responsiveness are less clear. We have studied the effects of 4 weeks of treatment with oral salbutamol controlled release (SCR) (8 mg b.d.) on airways responsiveness in mild asthmatics in a double-blind, placebo-controlled study. Airways responsiveness to inhaled methacholine, baseline FEV1 and plasma salbutamol levels was assessed 6 h, 48 h and 4 weeks after commencing treatment and again 24 h and 72 h after cessation of medication. When compared to placebo, SCR significantly attenuated AR at the 48-h time point only. There were no increases in AR recorded at any of the post-treatment time points. In addition, there were no significant differences in baseline FEV1 at any of the time-points studied, when compared to placebo. The change in AR at 48 h after starting treatment was probably due to functional antagonism of smooth muscle contraction. Importantly, there were no increases in AR recorded at either of the post-treatment time points.

A double-blind comparison of the effects of cefaclor and amoxycillin on respiratory tract and oropharyngeal flora and clinical response in acute exacerbations of bronchitis.

Fifty-one patients admitted to hospital with severe exacerbations of chronic bronchitis entered a double-blind trial of treatment with cefaclor (500 mg tds) compared with amoxycillin (500 mg tds) for 7 days. Twenty-six patients received cefaclor and 25 amoxycillin. Sputum and throat swabs were collected on admission, after 7 days of therapy and at outpatient follow-up, 3 weeks after treatment had finished. Clinical status and spirometry were assessed on admission and at the third, seventh and 28th day. There was no significant difference between the two regimes for clinical outcome, spirometry or numbers of infecting pathogens. Opportunistic colonization with resistant Gram-negative organisms and Candida species was highly prevalent on admission (56%) in both groups, perhaps because of previous antibiotic administration and general debility of the majority of patients. The high prevalence of opportunistic colonizing organisms persisted at follow-up (48%) with a significant excess of new organisms (Enterobacter cloacae, Klebsiella species and Candida species) present in sputum in the amoxycillin-treated patients. Cefaclor may be less damaging to normal flora than amoxycillin with a consequently reduced risk of colonization and superinfection of the respiratory tract with resistant Gram-negative organisms and yeasts.

Factors relating to the development of respiratory symptoms in coffee process workers.

After several cases of occupational asthma had been reported in a coffee processing factory in England, 197 coffee workers representing 80% of the production workforce were studied to determine the factors affecting the development of work related respiratory symptoms of wheeze, cough, and dyspnoea. Two computer administered questionnaires concerning the presence of respiratory symptoms and the occurrence of work related respiratory symptoms were used. Workers underwent skin prick testing to green coffee bean extract (GCB) and 11 common inhalant allergen extracts and bronchial provocation testing with methacholine. The presence of specific immunoglobulin E (IgE) antibodies to GCB and castor bean extract (CAB) were determined by a radioallergosorbent test (RAST). The prevalence of work related respiratory symptoms was 12.7%, bronchial hyperresponsiveness 30%, atopy 54%, positive GCB skin prick test 14.7%, positive GCB RAST 14%, and positive CAB RAST 14.7%. None of the workers was sensitised to fungi present in the factory and the numbers of certain species of fungi, despite being greater than may be found out of doors or in an uncontaminated indoor environment, were fewer than are generally associated with the presence of work related respiratory symptoms among agricultural workers. Storage mites were not isolated. Green coffee bean extract and CAB RAST were significantly correlated using the McNemar test but there was limited allergenic cross reactivity in RAST inhibition studies of the two extracts. The only factors that were significantly and independently associated with work related symptoms were CAB RAST and duration of employment. Bronchial hyperresponsiveness was not independently associated with work related respiratory symptoms. The significant independent associations of bronchial hyperresponsiveness included GCB RAST, duration of employment, and resting forced expiratory volume in one second. Exposure to CAB, a highly potent antigen, may be overriding the effects of other factors such a GCB, atopy, bronchial hyperresponsiveness, and smoking. This study suggests that CAB contamination remains a potential problem in the coffee processing industry and all efforts to eliminate it from the working environment should continue.