Effects of rapamycin, cyclosporin A, and dexamethasone on interleukin 5-induced eosinophil degranulation and prolonged survival.

Interleukin-5 (IL-5) enhances eosinophil degranulation and prolongs eosinophil survival. Rapamycin, cyclosporin A, and dexamethasone have been shown to influence either cytokine transcription, cytokine-mediated signalling, or degranulation by granulocytes. The study aimed to determine whether these agents inhibited IL-5-enhanced eosinophil survival or degranulation.

Elevated expression of messenger ribonucleic acid encoding IL-13 in the bronchial mucosa of atopic and nonatopic subjects with asthma.

Local secretion of cytokines by T cells within the bronchial mucosa, with consequent selective eosinophil influx, has been implicated in the pathogenesis of bronchial asthma. The cytokine IL-13 exhibits activities (selective eosinophil vascular adhesion by very late antigen-4/vascular cell adhesion molecule-1 interaction and promotion of IgE synthesis and "T112-type" T cell responses) that may be relevant to this process. We hypothesized that, compared with conditions in control subjects, elevated expression of messenger ribonucleic acid (mRNA) encoding IL-13 is a feature of the bronchial mucosa of both atopic (positive skin prick test result to at least one of a range of common aeroallergens) and nonatopic (negative skin prick test results and serum total IgE concentrations within the normal range) subjects with asthma.

Increased expression of mRNA encoding RANTES and MCP-3 in the bronchial mucosa in atopic asthma.

The selective recruitment of eosinophils into the mucosal lining of the airways is a prominent feature of atopic asthma, and is believed to be an important component in the disease pathogenesis. The precise stimuli responsible for the influx of eosinophils remain unclear. Using a semiquantitative reverse transcriptase polymerase chain reaction (RT-PCR) technique, the numbers of copies (relative to the "housekeeping" gene beta-actin) of messenger ribonucleic acid (mRNA) encoding the eosinophil-active chemotactic cytokines, the factor regulated upon activation in normal T-cells expressed and secreted (RANTES) and monocyte chemotactic protein-3 (MCP-3), was measured in bronchial biopsies from atopic asthmatic patients (n = 9), and compared with atopic nonasthmatic (n = 8) and nonatopic nonasthmatic (n = 8) control subjects.

IL-4 and IL-5 mRNA and protein in bronchial biopsies from patients with atopic and nonatopic asthma: evidence against "intrinsic" asthma being a distinct immunopathologic entity.

Intrinsic (nonatopic) asthma is considered to be a distinct pathogenetic variant of asthma since, unlike extrinsic (atopic) asthma, patients with the disease are skin test-negative to common aeroallergens, and have total serum IgE concentrations within the normal range. Nevertheless, the recent demonstration of increased numbers of cells expressing the high-affinity IgE receptor in bronchial biopsies from atopic and nonatopic asthmatic subjects, together with epidemiologic evidence indicating that serum IgE concentrations relate closely to asthma prevalence regardless of atopic status, suggests that IgE-mediated mechanisms may participate in the pathogenesis of both atopic and nonatopic asthma. Furthermore both variants of the disease are associated with bronchial mucosal eosinophilic inflammation.

Glucocorticoid resistant asthma: T-lymphocyte steroid metabolism and sensitivity to glucocorticoids and immunosuppressive agents.

We have previously shown that T-lymphocytes from clinically glucocorticoid (GC) resistant asthmatics are more refractory to dexamethasone suppression in vitro than those of GC sensitive asthmatics. We wished to extend these observations to compare three GCs used topically for asthma therapy (budesonide, beclomethasone dipropionate and fluticasone 17 alpha-propionate) and three immunosuppressive drugs (cyclosporin A, FK506 (tacrolimus) and mycophenolate mofetil) with dexamethasone for their antiproliferative effects on T-lymphocytes from GC sensitive and resistant asthmatics, and also to compare the rates of steroid metabolism by T-lymphocytes from these patients. Antiproliferative activity of the drugs was measured on peripheral blood T-lymphocytes activated with phytohaemagglutinin (PHA) and anti-CD3 antibody in vitro.

Safety of fibreoptic bronchoscopy in asthmatic and control subjects and effect on asthma control over two weeks.

Background: Concerns remain about the safety of bronchoscopy in asthma and there are few data on the effect of this procedure on asthma control in the days or weeks following bronchoscopy.

Methods: In an initial study of bronchoalveolar lavage and bronchial biopsies in asthmatic and control subjects, data on peak expiratory flow rates (PEFR) collected prospectively before and after the procedure were available from 21 of the 29 asthmatic subjects studied. These showed a median 23% fall in PEFR from baseline after bronchoscopy (range 3-58%).

Prednisolone treatment in asthma. Reduction in the numbers of eosinophils, T cells, tryptase-only positive mast cells, and modulation of IL-4, IL-5, and interferon-gamma cytokine gene expression within the bronchial mucosa.

We have tested the hypothesis that the beneficial effects of corticosteroids in asthma may result from reduction in the number of inflammatory cells infiltrating the bronchial mucosa with inhibition of cytokine gene expression. A randomized parallel group study was performed in 18 moderately severe asthmatic patients in whom an elective trial of corticosteroid treatment was indicated. Fiberoptic bronchoscopy was performed and bronchial biopsies taken from segmental carinae before and after 2 wk treatment with prednisolone (0.

Human eosinophils express messenger RNA encoding RANTES and store and release biologically active RANTES protein.

Eosinophils synthesize and store various cytokines with potential autocrine activity. We hypothesized that eosinophils synthesize and store RANTES, a CC-chemokine with potent eosinophil chemotactic activity. Expression of RANTES mRNA in highly purified eosinophil populations was detected by reverse transcription followed by polymerase chain reaction analysis.

Eosinophil cationic protein (ECP) and eosinophil protein X (EPX) concentrations in serum and bronchial lavage fluid in asthma. Effect of prednisolone treatment.

Background: Eosinophil granule proteins may contribute to bronchial hyperresponsiveness in asthma.

Objective: To measure eosinophil cationic protein (ECP) and eosinophil protein X (EPX) in serum and bronchial lavage fluid from 20 asthmatics and 16 control subjects. To assess the effect on these eosinophil proteins of corticosteroid treatment of asthma.

Secretion of the eosinophil-active cytokines interleukin-5, granulocyte/macrophage colony-stimulating factor and interleukin-3 by bronchoalveolar lavage CD4+ and CD8+ T cell lines in atopic asthmatics, and atopic and non-atopic controls.

Specific eosinophil accumulation and activation within the asthmatic bronchial mucosa are thought to occur at least partly through the actions of cytokines, including interleukin (IL)-5, IL-3 and granulocyte/macrophage colony-stimulating factor (GM-CSF). Although mRNA encoding some of these cytokines has been demonstrated in bronchoalveolar lavage (BAL) fluid cells and bronchial biopsies from asthmatics, it has yet to be established whether these cells produce the translated products and whether expression is associated with CD4+ T helper or CD8+ cytotoxic T cells. We addressed this problem by raising polyclonal CD4+ and CD8+ T cell lines from the BAL fluid of six atopic asthmatics, five atopic non-asthmatics and seven non-atopic non-asthmatic controls.

The effect of dexamethasone, cyclosporine, and rapamycin on T-lymphocyte proliferation in vitro: comparison of cells from patients with glucocorticoid-sensitive and glucocorticoid-resistant chronic asthma.

Inhibition of T-lymphocyte activation may provide a useful approach to the treatment of chronic severe asthma. We compared rapamycin, a novel immunosuppressive drug, with cyclosporine and dexamethasone for its effects in inhibiting proliferation of T lymphocytes from patients with glucocorticoid-resistant and glucocorticoid-sensitive asthma. Phytohemagglutinin-stimulated peripheral blood T lymphocytes from 11 patients with clinically glucocorticoid-resistant and 8 patients with glucocorticoid-sensitive chronic asthma were tested for sensitivity to these drugs in a highly reproducible proliferation assay.

Regular three monthly oral ciprofloxacin in adult cystic fibrosis patients infected with Pseudomonas aeruginosa.

In 31 adult patients with cystic fibrosis (CF) who were chronically infected with Pseudomonas aeruginosa we examined the effect of giving regular three monthly oral ciprofloxacin. Patients received ciprofloxacin or placebo for 10 days every 3 months for 1 yr in a randomized, double-blind, placebo-controlled study. During each course of treatment patients receiving ciprofloxacin reported an improvement in cough, sputum production and peak expiratory flow (PEF) P = < 0.

Prednisolone treatment in asthma is associated with modulation of bronchoalveolar lavage cell interleukin-4, interleukin-5, and interferon-gamma cytokine gene expression.

Although corticosteroids are effective in improving asthma symptoms and bronchial responsiveness, their mechanism of action is unknown. We examined whether changes in bronchial responsiveness with corticosteroid therapy of asthma are accompanied by a reduction in cytokine gene expression and eosinophil infiltration in the airways. Bronchoalveolar lavage (BAL) was performed in 18 patients with moderate asthma before and after 2 wk of treatment with prednisolone, 0.

Efficacy and safety of short-term administration of aerosolised recombinant human DNase I in adults with stable stage cystic fibrosis.

Chronic pulmonary infection is the major cause of morbidity and mortality in cystic fibrosis. High levels of DNA in the sputum make the sputum viscous and difficult to expectorate. Recombinant human deoxyribonuclease (rhDNase) in vitro has been shown to reduce the viscoelasticity of the sputum from CF patients.

Therapeutic potential and clinical efficacy of acid-resistant fungal lipase in the treatment of pancreatic steatorrhoea due to cystic fibrosis.

We investigated the therapeutic potential of an acid-resistant fungal lipase prepared from Aspergillus niger. We first demonstrated in vitro that it had a wide pH optimum of 2.5-5.

Eosinophils, T-lymphocytes, mast cells, neutrophils, and macrophages in bronchial biopsy specimens from atopic subjects with asthma: comparison with biopsy specimens from atopic subjects without asthma and normal control subjects and relationship to bronchial hyperresponsiveness.

Bronchial biopsy specimens were obtained by fiberoptic bronchoscopy from 21 atopic subjects with asthma, 10 atopic subjects without asthma, and 12 normal healthy control subjects. With immunohistochemical techniques and a panel of monoclonal antibodies, inflammatory cells were identified and counted in the bronchial mucosa. The mean number of leukocytes (CD45+) and T-lymphocytes (CD3+, CD4+, and CD8+) at two airway levels in the subjects with asthma tended to be higher than in the other groups, but this difference did not achieve statistical significance.

Identification of activated T lymphocytes and eosinophils in bronchial biopsies in stable atopic asthma.

We have used immunohistochemistry and monoclonal antibodies to analyze the phenotypic composition and activation status of the cellular infiltrate of bronchial biopsies obtained by fiber optic bronchoscopy of 11 atopic asthmatic subjects (FEV1% predicted range 78 to 114), 9 atopic nonasthmatic control subjects, and 10 normal healthy subjects. Examination of mucosal biopsies obtained from both central (level I) and subsegmental (level II) bronchi showed that the highest number of CD45-, DC3-, DC4-, and CD8-positive cells were found in the group with asthma. There was a significant increase in the number of interleukin-2 receptor (CD25)-positive cells (a marker of lymphocyte activation) at airway level I in the asthmatic group compared with both nonasthmatic atopic (p less than 0.

High dose salbutamol in chronic airflow obstruction: comparison of nebulizer with Rotacaps.

Patients with severe chronic airways obstruction often respond poorly to inhaled salbutamol in conventional dosage from a pressurized aerosol. We have investigated the response to high dose salbutamol in 18 patients with chronic airways obstruction (mean age 64.4 years, mean FEV1 40.

Outcome of asthma induced by isocyanates.

Isocyanates are widely used in industry for the manufacture of polyurethanes. Although they are recognized as an important cause of occupational asthma, it is unclear whether asthma persists after avoidance of exposure. We have followed up 50 cases, all of whom had avoided exposure for at least 4 years.

Cold air test: a simplified standard method for airway reactivity.

A simple and standardized test has been developed to measure airway responsiveness to cold dry air. This consists of stepwise increases in ventilation of dry subfreezing air at 10, 20, 40 and 60% of predicted indirect maximum breathing capacity (IMBC). For each step, the inhalation time was 3 min.

Neutrophil chemotactic factor in exercise- and hyperventilation-induced asthma.

Elevated levels of the mast-cell-associated serum neutrophil chemotactic factor (NCF) and an increase in blood basophil counts were observed in 6 atopic asthmatics during exercise-induced asthma (EIA). These changes were not found when the same degree of airways obstruction was elicited in the same subjects by isocapnic hyperventilation (ISH) with cold air. The NCF was unlikely to be related to the basophilia alone, because asthmatics without EIA who underwent the same exercise task, produced a similar basophilia but significantly less NCF.

The link between exercise, respiratory heat exchange, and the mast cell in bronchial asthma.

There are two apparently conflicting theories on the pathogenesis of exercise-induced asthma. One view is that exercise-induced asthma is directly related to respiratory heat exchange and that mast cells are not involved. The other theory explains exercise-induced asthma on the basis of a temperature-independent release of mast-cell mediators.

Direct recordings of the temperatures in the tracheobronchial tree in normal man.

In an effect to determine how far inspired air could penetrate into the respiratory tract before being brought to body conditions, we measured the temperature in the airways of the anterior basilar segment of the right lower lobe in five normal subjects while they breathed air at subfreezing and ambient conditions. During quiet breathing, most of the heating of the incoming gas took place in the upper airways as expected. However, as the thermal burden was increased by rapid inspirations, frigid air, and hyperventilation, the temperature of the distal airways progressively fell and the point at which the incoming air reached body conditions moved deep into the periphery of the lung.