Eosinophil activation in the tissue: synthetic steroid, budesonide, effectively inhibits the survival of eosinophils isolated from peripheral blood but not nasal polyp tissues

We investigated the effect of a potent synthetic steroid, budesonide (BUD), on the survival of nasal polyp (NP) derived eosinophils (EOS). BUD, at the highest dose used, 10(-6) M, decreased this survival but only by approximately one third. We speculated that the relatively small inhibitory effect of budesonide on the survival of NP-EOS could be the result of these EOS being exposed to substantial amounts of GM-CSF, IL-5 or IL-3. In this regard, we detected 148 pg of GM-CSF per 150 mg of tissue, which approximately contained 106 of eosinophils, in the supernatant of NP explants for 24 h without any stimulation. Contents of both IL-5 and IL-3 were much less. We further studied survival of PB-EOS exposed to rhGM-CSF and found that 10(-6) M of BUD could only inhibit by less than one third the survival of PB-EOS exposed to an amount of rhGM-CSF, similar to that detected in the supernatant of NP explants. In addition, we exposed PB-EOS to 200 pg/ml of rhGM-CSF for a relatively long period of time (4 days) in order to mimic chronic exposure in the tissue and found that the survival of these cells was prolonged to the extent similar to that observed in NP-EOS. Our data suggests that the prolonged spontaneous survival of NP-EOS ex vivo is likely the result of sustained in vivo exposure to GM-CSF and budesonide has a smaller inhibitory effect in the survival of these eosinophils as compared to those from peripheral blood.

Efficacy and tolerability of fluticasone propionate nasal drops 400 microgram once daily compared with placebo for the treatment of bilateral polyposis in adults

BACKGROUND

Chronic eosinophilic rhinosinusitis underlies a range of respiratory disorders including nasal polyposis. Surgical and medical methods are used to control polyps, with topical steroids commonly being used for their anti-inflammatory properties. Fluticasone propionate nasal drops (FPND) is a formulation developed specifically for an effective and well tolerated corticosteroid treatment of nasal polyposis.

OBJECTIVES

To assess efficacy and tolerability of FPND in the treatment of bilateral nasal polyposis in adults.

METHODS

This multicentre, randomized, parallel-group study compared FPND 400 microgram once daily (o.d.) with placebo for 12 weeks in adult patients with mild to moderate bilateral polyposis. The primary efficacy endpoint was visual assessment of polyp size by the physician at monthly clinic visits. Nasal blockage, rhinitis, peak nasal inspiratory flow (PNIF), olfactory function and requirement for polypectomy were also assessed at visits. The patients kept diary card records of symptoms, PNIF, and use of rescue antihistamine. Additional safety data were provided by a 12-week open extension, when all patients received FPND 400 microgram o.d.

RESULTS

After 12 weeks double-blind treatment with FPND (n = 52) or placebo (n = 52), polyp size was reduced in 27% and 16% of patients, respectively; clinical reduction of nasal blockage significantly favoured FPND over placebo (55% vs 22%; P = 0.002), and clinic PNIF had increased significantly with FPND (by 52 L/min vs -3 L/min for placebo; P < 0.001). Diary card measurements showed significant benefits of FPND vs placebo for daily PNIF, nasal blockage, rhinitis and use of loratadine rescue medication. Both treatments were well tolerated and no serious adverse events occurred during randomized treatment. Epistaxis was more frequent with FPND than placebo but was generally mild and did not result in withdrawals. Mean serum cortisol levels did not change significantly with either treatment.

CONCLUSION

This study showed FPND 400 microgram o.d. to be an effective and well tolerated treatment for bilateral nasal polyposis in adults.

TNF-alpha dysregulation in asthma: relationship to ongoing corticosteroidtherapy

BACKGROUND

Tumour necrosis factor-alpha (TNF-alpha) is a major proinflammatory cytokine that is thought to be important in the pathogenesis of asthma. However, alterations in systemic regulation of this cytokine in asthma have not been examined in the context of corticosteroid therapy.

OBJECTIVES

To examine the ability of peripheral blood mononuclear cells (PBMC) from three different groups of patients with asthma requiring varying amounts of inhaled corticosteroids (ICS) for clinical control, and to examine cells from age- and sex-matched nonasthmatic patients to produce TNF-alpha.

DESIGN

All patients with asthma had a positive methacholine challenge test. 'High dose' ICS patients with asthma required ICS greater than or equal to 800 microg/day. 'Medium dose' patients with asthma were on less than or equal to 500 microg/day of ICS, whereas 'no ICS' patients with asthma had received no ICS for at least three months. Each patient with asthma was examined in parallel with an age- and sex-matched, nonasthmatic, nonatopic control subject. Cells were cultured (with or without the addition of potential stimulators phytohemagglutinin, lipopolysaccharide, formyl-methionine-leucine-phenylalanine or antihuman CD3), and TNF-alpha production was assessed by ELISA.

MAIN RESULTS

PBMC from both high dose ICS (n=8) and no ICS (n=11) patients with asthma produced more than twice the amount of TNF-alpha than cells from matched nonasthmatic control patients (P<0.01) when cultured alone or in the presence of each stimulus (P<0.05). In contrast, there was no significant difference in TNF-alpha production between medium dose ICS patients with asthma and control patients. A group of asymptomatic atopic patients (n=6) did not have an increased level of TNF-alpha production.

CONCLUSIONS

Increases in TNF-a production within the PBMC compartment can be observed in both patients with asthma receiving high dose ICS and in a group of patients with mild asthma receiving no ICS therapy, but not in patients with asthma receiving a medium dose of ICS or atopic patients.

Nonasthmatic chronic cough: No effect of treatment with an inhaled corticosteroid in patients without sputum eosinophilia

BACKGROUND

Inhaled corticosteroids are effective in suppressing a chronic cough without asthma associated with sputum eosinophilia.

OBJECTIVE

To investigate the inflammatory characteristics in the induced sputum of patients with a chronic cough without asthma or known cause and the effects of budesonide treatment on chronic cough in those patients.

PATIENTS AND METHODS

Forty-four adults (mean [minimu, maximum] age of 45 years [20,75], 28 women, 17 atopic subjects and 32 nonsmokers], with a daily bothersome cough for at least one year and who had no evidence of asthma or other known cause for the cough, were consecutively enrolled. The trial was a randomized, double-blind, controlled parallel group trial of budesonide 400 mg twice daily for two weeks versus placebo. Patients then received open administration of the same dose of budesonide for a further two weeks. Sputum was induced before and at the end of each treatment period. Cough severity was documented by a visual analogue scale.

RESULTS

Thirty-nine (89%) patients produced mucoid sputum after induction on at least one study visit. At baseline, the majority (59%) had a mild elevation in the median proportion of neutrophils (65%). All had elevated fluid phase levels of fibrinogen (3200 mg/L) and albumin (880 mg/L), and high levels of interleukin-8 and substance P. Interleukin-8 correlated with neutrophils (rho=0.72, P<0.001), fibrinogen (rho=0.65, P<0.001), albumin (rho=0.67, P=0. 001) and eosinophil cationic protein (rho=0.60, P=0.001). Substance P correlated with albumin (rho=0.60, P=0.006). No subject had an increase in eosinophils. Treatment with budesonide did not affect cough or sputum measurements.

CONCLUSIONS

Patients with nonasthmatic chronic cough enrolled in this study had evidence of a mild neutrophilia and/or microvascular leakage. Chronic cough did not respond to treatment with budesonide, perhaps because the cause was not associated with sputum eosinophilia.

Diagnosing occupational asthma: use of induced sputum

The diagnosis of occupational asthma (OA) needs to be made with as much objective evidence as possible. If there is airway inflammation, measurement of this should be an asset. The objective of this study was to investigate whether there is an increase in induced sputum and blood eosinophils and eosinophil cationic protein (ECP) in OA after work exposure. Patients were assessed after a 2-4 week period at work and away from work with cell counts and ECP assays performed blind to the clinical data. They were considered to have OA if symptoms were worse at work and there was a fall in forced expiratory volume in one second (FEV1) > or =20% or in the provocative concentration of methacholine causing a 20% fall in FEV1 (PC20) of four-fold or more compared with away from work. Patients whose symptoms were worse at work but had a change in FEV1 of <20% and in methacholine PC20 of less than four-fold were considered as controls. Sixteen patients were studied. Ten had OA and six were controls. Patients with OA had a significant increase in median (interquartile range) sputum eosinophils and ECP when at work compared with the periods out of work, 10.0 (17.05) versus 0.8 (1.6)% (p=0.007) and 3,840 (6,076) versus 116 (180) microg x L(-1) (p=0.01). They also had a higher blood eosinophil count, 0.3 (0.5) x 10(9) versus 0.2 (0.1) x 10(9) x L(-1) (p=0.013), and a trend towards higher serum ECP levels, 44.0 (20.0) versus 32.0 (18.5) microg x L(-1) (p=0.07). In conclusion, the proportion of eosinophils and levels of eosinophil cationic protein in sputum are particularly high at work in patients with occupational asthma, suggesting that the measurement of these factors can supplement other physiological outcomes in establishing the diagnosis of occupational asthma.

Prednisone-dependent asthma: inflammatory indices in induced sputum

The kinetics of changes in inflammatory indices in induced sputum from eight prednisone dependent asthmatics whose minimum clinical maintenance and exacerbation doses were known were investigated. The study began on the last day of a course of 30 mg prednisone daily for one week. Thereafter, the daily prednisone was reduced in a structured way to below the maintenance dose. This treatment was continued until a clinical exacerbation occurred. Prednisone 30 mg daily was then given again for one week. The mean duration of prednisone reduction was 7.4 weeks and the median dose was 7.5 mg x day(-1). Increases in sputum eosinophils preceded increases in blood eosinophils by 4 weeks and worsening of symptoms and forced expiratory volume in one second by 6 weeks. The clinical exacerbation was also accompanied by sputum neutrophilia and increases in sputum eosinophil cationic protein (ECP), fibrinogen and interleukin (IL)-5. Treatment with prednisone suppressed median sputum eosinophilia (from 16.3 to 0%, p<0.001), decreased sputum ECP (from 7,480 to 700 microg x L(-1), p = 0.01), but did not improve neutrophil numbers, fibrinogen or IL-5. The results show that the reduction of prednisone treatment in prednisone-dependent asthmatics evokes a severe airway eosinophilic inflammatory response. Clinical and blood indices deteriorate later than those in sputum suggesting that sputum examination may be useful to identify the minimum regular dose of prednisone required in these patients.

Comparison of budesonide Turbuhaler with budesonide aqua in the treatment of seasonal allergic rhinitis. Rhinocort Study Group

OBJECTIVE

To compare the effect of budesonide Turbuhaler 400 microg/day with budesonide aqua 256 microg/day in the treatment of seasonal allergic rhinitis (SAR). Secondarily to ascertain patients' preferences for the two nasal devices and to assess quality of life.

DESIGN

Randomized, multicentre, double-blind, double- dummy, parallel groups study.

SETTING

Private practices and hospital clinics in Ontario, Quebec and Manitoba.

POPULATION

Two hundred and eighty-four out-patients with SAR, who were symptomatic during the ragweed season, volunteered for enrolment (243 randomized).

RESULTS

Mean daily nasal symptom scores were significantly reduced with treatment. There were no statistically significant changes from baseline for eye symptoms. Most patients (more than 80%) achieved substantial control of their symptoms with budesonide. The most common nasal and non-nasal adverse events for both groups were epistaxis and headache. Turbuhaler was easier to use and more convenient to carry, had less of an unpleasant taste, and caused less nasal irritation than the aqua spray. More than twice as many patients preferred Turbuhaler to the aqua spray (69% versus 31%). Improvement in quality of life from baseline to clinic visits was statistically significant in both groups.

CONCLUSION

Once daily use of 256 mg of budesonide aqua and 400 mg of budesonide Turbuhaler are equally safe and efficacious in the treatment of SAR. Patients preferred the budesonide powder formulation delivered via Turbuhaler two to one over the aqua formulation.

Sputum eosinophilia predicts benefit from prednisone in smokers with chronic obstructive bronchitis

A reliable predictor of benefit from corticosteroid treatment in patients with chronic airflow limitation is needed. In a single-blind, sequential crossover trial of placebo and prednisone (30 mg/day) treatment, with each given for 2 wk, we investigated whether an increased proportion of sputum eosinophils (>= 3%) predicts a beneficial effect of prednisone in smokers with severe obstructive bronchitis. Patients were seen before and after each treatment. Clinical measurements were made blind to the laboratory findings and vice-versa. Eighteen of 20 patients completed the study. Eight had sputum eosinophilia and similar clinical and physiologic characteristics to those of 10 patients without a finding of sputum eosinophilia. Only in patients with sputum eosinophilia did prednisone, as compared with placebo, produce a statistically significant and clinically important mean effect on effort dyspnea of 0.8 (95% confidence interval [CI]: 0.3 to 1.2), p = 0.008, and in quality of life of 1.96 (95% CI: 0.5 to 3.3), p = 0.01, associated with a small improvement in FEV1 of 0.11 L (95% CI: - 0.04 to 0.23 L), p = 0.05. In these patients, prednisone also produced a significant decline in the median sputum eosinophil percentage, from 9.7% to 0.5% (p = 0.002), eosinophil cationic protein (ECP), from 6, 000 microgram/L to 1,140 microgram/L (p < 0.001), and fibrinogen, from 25. 3 mg/L to 5.4 mg/L (p < 0.001). These findings indicate that in smokers with severe airflow limitation, sputum eosinophilia predicts a beneficial effect of prednisone treatment. Improvement in FEV1, after prednisone treatment in this population, is small, and may not be appreciated in clinical practice.

Asthma and natural colds. Inflammatory indices in induced sputum: a feasibility study

We examined the feasibility of using induced sputum to evaluate the airway inflammatory response to natural acute respiratory virus infections. We recruited eight asthmatics and nine healthy subjects on Day 4 of a cold. Viral infection was confirmed in six of the asthmatics (influenza A or B) and six of the healthy subjects (influenza A, rhinovirus, adenovirus, respiratory syncytial virus, and coronavirus). In the subjects with confirmed virus infection, five of the asthmatics had an objective exacerbation of asthma during the cold. Their sputum on Day 4 showed a high median total cell count of 19.7 x 10(6) cells/ml with a modest neutrophilia (58. 5%) and high levels of interleukin-8 (IL-8) (16,000 pg/ml), eosinophilic cationic protein (ECP) (1,880 microgram/L) and very high levels of fibrinogen (250 mg/L). In contrast, the proportion (1.3%) and absolute number of eosinophils was low. IL-2 levels were within the normal range, whereas IL-5 and interferon gamma were under the limit of detection of the assays. In the healthy subjects with a confirmed virus infection the sputum findings were qualitatively similar but significantly less prominent. Sputum IL-8 on Day 4 was strongly correlated with neutrophils (rs = 0.8, p < 0.001). This correlation was also significant when each group was analyzed separately. On Day 21 there was a fall in the absolute number of neutrophils and in ECP and fibrinogen levels in both groups. Similar results were found in the two asthmatic and three healthy subjects with a cold of comparable severity but in whom viral infection was not confirmed. We conclude that induced sputum examination can be used to study the effects of natural colds and influenza on the airways of the lungs. The results also suggest that natural colds, on Day 4, cause neutrophilic lower airway inflammation that is greater in asthmatics than in healthy subjects. The greater inflammatory response in asthmatics may be due to the changes associated with trivial eosinophilia or to the different viruses involved.

Induced sputum, bronchoalveolar lavage and blood from mild asthmatics: inflammatory cells, lymphocyte subsets and soluble markers compared

Airway inflammation in asthma can be measured directly by invasive bronchoalveolar lavage (BAL), directly and relatively noninvasively by induced sputum and indirectly from peripheral blood. We compared cellular and fluid phase indices of inflammation in induced sputum, BAL and blood from 11 adults with mild stable asthma. On one day, induced sputum selected from saliva was collected and on the next, blood and BAL. Median results of sputum compared with BAL showed a higher number of nonsquamous cells (53 versus 0.8 x 10(6) cells x mL(-1), p=0.003), more neutrophils (34.3 versus 1.0%, p<0.001), CD4+ and CD19+ T-cells (76.5 versus 54.7%, p=0.01 and 5.2 versus 1.1%, p=0.03, respectively), fewer macrophages (603 versus 95.0%, p=0.002) and markedly higher levels of eosinophil cationic protein (ECP) (264 versus 2.0 microg x L(-1), p<0.001), tryptase (17.6 versus 2.2 UI x L(-1), p<0.001) and fibrinogen (1,400 versus 150 microg x L(-1), p=0.001). Sputum and BAL neutrophils and CD4+ T-cells were strongly correlated. Sputum and BAL differed from blood by having higher proportions of T-cells (94.9 and 98.9% versus 87.7%, p=0.002) and lower proportions of CD19+ T-lymphocytes (p=0.04 and 0.006). Sputum also differed from blood by having higher proportions of CD4+ T-cells (76.5 versus 51.4%, p=0.001), lower proportions of CD8+ cells (24.0 versus 403%, p=0.04) and a higher CD4+/CD8+ ratio (3.3 versus 1.4, p=0.01). We conclude that in mild asthmatics, sputum, bronchoalveolar lavage and blood measure different compartments of inflammation. Induced selected sputum has the advantage over bronchoalveolar lavage of higher density of cell recovery and stronger signal for fluid-phase markers.

Clinical and nasal irrigation fluid findings in perennial allergic rhinitis

Ten patients with perennial allergic rhinitis and 10 healthy subjects were studied to determine most discriminative nasal irrigation fluid marker(s) and to compare samples that were collected at baseline and over a 1-hour period, every 15 minutes. The latter were pooled and designated 1-hour sample. In the nasal irrigation we investigated the following inflammatory cells and soluble mediators: eosinophils, neutrophils, granulocyte-macrophage colony-stimulating factor, interleukin-4, interleukin-6, interleukin-8, ECP, EPX, MPO, leukotriene C4, leukotriene B4, prostaglandin E2, tryptase and fibrinogen. Patients with PAR were then treated for 2 weeks with the topical nasal steroid. The only marker that discriminated patients with perennial allergic rhinitis and healthy subjects was eosinophil count (EO%): correspondingly 14.01 +/- 5.8 and 0.18 +/- 0.09, (M +/- SD). Difference between the studied groups did not depend on the time of irrigation, baseline or 1-hour. EO% was also the only marker of a clinically successful treatment with the nasal steroid, 14.01 +/- 5.8 and 0.87 +/- 0.4, before and after treatment respectively. We conclude that EO% is the most sensitive inflammatory marker of perennial allergic rhinitis, and that baseline nasal irrigation can be used to study nasal mucosal inflammation.

Markers of inflammation in induced sputum in acute bronchitis caused by Chlamydia pneumoniae

Little is known of the inflammatory characteristics of acute infections of the respiratory tract caused by virus and unusual bacteria such as Chlamydia pneumoniae. A case is reported in whom inflammatory indices in sputum were used to investigate, for the first time, the airway inflammation during an episode of acute bronchitis caused by C pneumoniae. The patient presented with a dry cough of five days duration. C pneumoniae was identified by polymerase chain reaction (PCR) in a nasopharyngeal swab collected on day 5. Virological studies were negative. Clinical and inflammatory indices in induced sputum were measured on days 6, 8, and 11. The cough cleared spontaneously by day 11. Forced expiratory volume in one second was normal throughout. Sputum findings identified intense airway inflammation characterised by increased total cell and lymphocyte counts followed by an increase in neutrophils and a decrease in the CD4/CD8 ratio, activation of CD8 lymphocytes, and exudation as indicated by an increase in fluid phase fibrinogen. These observations suggest that sputum might be useful to monitor an inflammatory/immune response of the airway in acute infections.

Stem cell factor in nasal polyposis and allergic rhinitis: increased expression by structural cells is suppressed by in vivo topical corticosteroids

BACKGROUND

Mast cells are increased in nasal polyp (Np) and allergic rhinitis (AR) tissue and are suppressed by topical corticosteroid treatment. Stem cell factor (SCF), a mast cell growth and survival factor, may explain these phenomena.

OBJECTIVE

We investigated structural cell gene expression and production of SCF in nasal tissues in patients who had received and who had not received in vivo intranasal corticosteroid therapy.

METHODS

Northern blot analyses for messenger RNA and ELISA for biologically active SCF protein from cultured Np epithelial cells and fibroblasts were performed. Immunostaining for SCF in cultured and tissue nasal structural cells in the presence or absence of steroid treatment was also performed.

RESULTS

We detected significant expression of SCF mRNA and protein by cultured Np epithelial cells and Np fibroblasts; Np fibroblast SCF supported the differentiation of mast cells in vitro. There were more immunoreactive SCF-positive Np epithelial cells in patients with AR than in control subjects (97.2 +/- 2.8 vs 45.6 +/- 22.0%; p < 0.0001). SCF that could be immunostained was significantly diminished overall in Np structural cells in the group given in vivo steroid treatment, with a modest (trend to significant) effect on any given cell type analyzed. In vitro treatment with budesonide of SCF-producing fibroblasts demonstrated inhibition of unstimulated, primary Np fibroblasts but not of IL-1-stimulated fibroblasts or transformed cell lines.

CONCLUSIONS

Human Np and AR tissue structural cells express and produce increased SCF. Our in vitro studies suggest that intranasal steroids blunt SCF expression in Nps, an effect that may be responsible for a decrease in mast cells and symptoms.

Induced sputum cell and fluid-phase indices of inflammation: comparison of treatment with dithiothreitol vs phosphate-buffered saline

Treatment of sputum with dithiothreitol (DTT) gives reliable measurements of cellular and fluid-phase markers of airway inflammation. We investigated the extent to which DTT treatment influences these measurements as compared with phosphate-buffered saline (PBS). Hypertonic saline-induced sputum, collected from 20 asthmatic subjects, was examined within 2 h. All portions which looked more solid (less fluid) than saliva were collected from the expectorate. The selected sputum was then divided into two portions: one treated with one volume of DTT and one volume of PBS, the other with two volumes of PBS. The filtrates were assessed blind for total and differential cell count, viability, and fluid-phase eosinophil cationic protein (ECP), fibrinogen, interleukin (IL)-5 and IL-8. Sputum treated with DTT compared with PBS had lower proportions of viable cells (median 66 versus 74%; p=0.003). In contrast, DTT-treated sputum had higher total cell counts (median 8.8 vs 2.8 x 10(6) mL(-1); p<0.001) and levels of ECP (median 1340 vs 584 mg x L(-1); p<0.001) The measurements were similar with respect to the proportion of eosinophils, neutrophils, lymphocytes, macrophages, and fluid-phase fibrinogen, IL-5 and IL-8. We conclude that dithiothreitol disperses cells more effectively and that this might account for the higher levels of eosinophil cationic protein. Dithiothreitol may affect cell viability, but the changes are not relevant with respect to cell counts. Additionally, dithiothreitol does not seem to influence the other measurements performed.

Sputum in severe exacerbations of asthma: kinetics of inflammatory indices after prednisone treatment

We have investigated the time-course of symptoms, forced expiratory volume in one second (FEV1), and the airway inflammatory changes in sputum selected from saliva and blood of 10 patients with severe exacerbation of asthma betwen presentation and after 1, 2, 3, 7, and 21 days of treatment. The sputum was induced by a modified standard protocol, and we examined its safety. The severe exacerbation of asthma was defined by the presence of nocturnal symptoms disturbing sleep and/or the need for inhaled short acting beta2-agonist > or = 8 puffs/d and an FEV1 after bronchodilator < 60% of predicted. The treatment consisted of additional prednisone 30 mg daily for 5 d followed by reduction to zero by day 10. Abnormal findings [median (interquartile range)] in spontaneous and induced sputum included low viability of cells [52.0 (34.0)%]; eosinophilia [20.0 (16.4)%]; many free eosinophil granules; and increased levels of fluid-phase ECP [1960 (9204) microg/L], fibrinogen [6045 (10720) microg/L], and IL-5 [160 (212) pg/ml]. Peripheral blood eosinophils [10.4 (7.6)%] and ECP levels [34.0 (35.0) microg/L] were increased. After treatment, symptoms, FEV1, blood eosinophilia, and serum ECP improved in the first 24 h. Sputum eosinophils and ECP did not improve until 48 h and fibrinogen not until 7 d. The improvement in sputum eosinophils and ECP levels was correlated with improvement of FEV1 and in fluid-phase IL-5. Thirty sputum inductions were performed safely in the majority with inhaled isotonic or 3% saline (23.3% or 63.3%, respectively) over a short duration (mean 8.4 min). The patients who had a fall in FEV1 of > or = 10% (10 occasions) after induction differed from those with a fall of < 10% only in the amount of inhaled beta2-agonist used by the patients in the preceding 24 h [8.0 (5.0) versus 4.0 (3.0) puffs/d, p = 0.01]. The results suggest that spontaneous or induced sputum can be used safely to follow the kinetics of effects of antiinflammatory treatment in a severe exacerbation of asthma. The clinical and blood indices improve before those in sputum, raising the possibility that examination of sputum is a better guide in these patients to follow the effects of treatment.

Occupational sensitization to lactase

Occupational sensitization to lactase is reported in workers formulating and packaging this consumer product, which is used for the relief of gastrointestinal symptoms caused by intolerance to lactose. Allergic rhinitis, conjunctivitis, and some cases of asthma were noted. There was suggestive evidence that atopic individuals may be at greater risk of sensitization. Lactase should be added to the list of potential occupational respiratory sensitizers.

Measuring airway inflammation in asthma: eosinophils and eosinophilic cationic protein in induced sputum compared with peripheral blood

BACKGROUND

Airway eosinophilic inflammation is a characteristic feature of asthma. This can be assessed directly by measurement of eosinophils and eosinophilic cationic protein (ECP) in sputum or indirectly by measurement of the same markers in blood. We investigated the performance of these markers of airway eosinophilic inflammation in a population of patients with asthma compared with control subjects and the extent to which the markers differed.

METHODS

In a cross-sectional study, subject characteristics were documented on day 1 and induced sputum and blood samples were obtained on day 2. Nineteen patients with asthma and 20 control subjects (10 healthy subjects and 10 smokers with nonobstructive bronchitis) were consecutively enrolled in the study. Sputum (selected from saliva) and blood samples were processed by persons blind to the clinical details. Results are presented as median values (minimum-maximum); differences were measured by Mann-Whitney U test. The accuracy of the tests (sensitivity and specificity) was measured by plotting the data in receiver-operating characteristic (ROC) curves and comparing the areas under the curve for each marker.

RESULTS

Patients with asthma in comparison with control subjects had a higher proportion of sputum eosinophils (5.2% [0.2% to 93%] vs 0.3% [0% to 1.7%], p < 0.001), higher numbers of blood eosinophils (350.0 x 10(6)/L [144.0 to 1520.0 x 10(6)/L] vs 155.0 x 10(6)/L [34.0 to 426.0 x 10(6)/L], p = 0.003), and higher levels of ECP in sputum (1040.0 micrograms/L [76.8 to 32,000.0 micrograms/L] vs 455.3 micrograms/L [54.4 to 1280.0 micrograms/L], p = 0.001) but not in serum (25.0 micrograms/L [5.6 to 52.4 micrograms/L] vs 16.5 micrograms/L [3.3 to 36.0 micrograms/L], p = 0.08). Markers of airway inflammation in induced sputum and blood samples were correlated with clinical and physiologic variables. The area under the ROC curve showed that eosinophils in sputum (0.90) are significantly more accurate markers than blood eosinophils (0.72) and serum ECP (0.67) (p = 0.02). Although the area under the ROC curve for sputum ECP was greater than those for blood eosinophils and serum ECP, the differences could have occurred by chance (p > or = 0.1).

CONCLUSION

We conclude that the proportion of eosinophils in sputum is a more accurate marker of asthmatic airway inflammation than the proportions of blood eosinophils or serum ECP.

Spontaneous and induced sputum to measure indices of airway inflammation in asthma

Inhalation of hypertonic saline to induce sputum may alter cells and fluid-phase markers in sputum. We have compared indices of inflammation in sputum produced spontaneously with sputum induced by an aerosol of hypertonic saline. Twenty-three asthmatics produced spontaneous followed by induced sputum on the same day. The sputum specimen was separated from saliva within 2 h, dispersed with dithiothreitol (DTT) and processed to obtain cytospins and supernatant. The statistical power to detect a 20% difference in sputum parameters was > 90%. Results are expressed as median and interquartile range [IQR]. Induced sputum had a higher proportion of viable cells (77.0 [19.0] versus 47.0 [38.0]%, p < 0.001), less squamous cell contamination (1.0 [1.2] versus 1.8 [34.0]%, p < 0.001) and better quality cytospins (score of 8.0 [4.0] versus 4.0 [2.0], p < 0.001). It also had lower fluid-phase levels of eosinophil cationic protein (ECP) (1,358 [1,102] versus 1,574 [2,479] microg/L) and fibrinogen (1,560.0 [3,130.0] versus 4,350.0 [5,970.0] ng/ml) but only the latter was significantly different (p = 0.02). Induced sputum was similar to spontaneous sputum in weight (200.0 [219.0] versus 270.0 [227.0] mg), total cell count (3.3 [4.1] versus 3.5 [4.5] x 10(6)/ml), proportion of nonsquamous cells, and levels of tryptase. The agreement between induced and spontaneous measurements was good, but fluid-phase levels were affected by the low viability of some spontaneous samples. We conclude that for the indices measured in asthmatic subjects, induced sputum separated from saliva is similar to lower respiratory secretions expectorated spontaneously and has the advantage of better cell viability.

Isolated late asthmatic reaction after exposure to a high-molecular-weight occupational agent, subtilisin

High-molecular-weight agents generally induce immediate asthmatic reactions. We report the case of a subject who experienced a reaction that started after the first hour following exposure to subtilisin, a high-molecular-weight occupational agent. Any occurrence of immediate reaction was ruled out by measuring both FEV1 and lung volumes every 10 min in the first hour. This reaction was IgE-mediated as shown by immediate skin reactivity and increased specific IgE levels.

Outcome of specific bronchial responsiveness to occupational agents after removal from exposure

A decrease in specific bronchial responsiveness (SBR) could occur after removal from exposure to an agent causing occupational asthma as a result of loss of immunologic and/or nonspecific bronchial reactivity (NSBR). We studied 15 subjects with occupational asthma (eight to a high- and seven to a low-molecular-weight agent, isocyanate in all instances), proved by specific inhalation challenges (SIC) done 2 yr or more before. Subjects were reexposed in the same way as in the initial SIC: for subjects who did not react, the exposure was increased until either an asthmatic reaction occurred or a maximum of 2 h was reached. NSBR was assessed before and after SIC. Subjects had a decrease in their SBR if the total dose of agent necessary to induce asthmatic reaction was greater by twofold compared with the initial SIC. There was a significant improvement in NSBR in seven of 15 subjects. Nine of 15 subjects (60%) had a decrease in their SBR. Only one had a complete loss of SBR. Changes in NSBR, molecular weight of the offending agent, decrease of antibody level against offending agents, or duration of exposure at work did not explain the decrease in SBR. We conclude that after removal from exposure to the offending agent a majority of subjects (60%) show a decrease but a persistence of SBR to high- and low-molecular-weight agents.

Indices of airway inflammation in induced sputum: reproducibility and validity of cell and fluid-phase measurements

Methods to examine sputum for indices of airway inflammation are evolving. We have examined the repeatability and the validity of an improved method to measure sputum cells and fluid-phase eosinophil cationic protein (ECP), major basic protein (MBP), eosinophil-derived neurotoxin (EDN), albumin, fibrinogen, tryptase, and interleukin-5 (IL-5). Sputum was induced with hypertonic saline twice within 6 d in 10 healthy subjects, 19 stable asthmatics, and 10 smokers with nonobstructive bronchitis. The method included the processing of freshly expectorated sputum separated from saliva, treatment with a fixed proportion of dithiothreitol 0.1% followed by Dulbecco's phosphate-buffered saline, making cytospins, and collecting the supernatant. The reproducibility of measurements, calculated by the intraclass correlation coefficient, was high for all indices measured with the exception of total cell counts and proportion of lymphocytes. Asthmatics, in comparison with healthy subjects and smokers with bronchitis, had a higher proportion of sputum eosinophils (median percent 5.2 versus 0.5 and 0.3), metachromatic cells (0.3 versus 0.07 and 0.08), ECP (1,040 micrograms/L versus 288 and 352), MBP (1,176 micrograms/L versus 304 and 160), and EDN (1,512 micrograms/L versus 448 and 272). Asthmatics differed from healthy subjects, but not from smokers with bronchitis, in the proportion of neutrophils (46.9% versus 24.1%), albumin (704 versus 288 micrograms/mL), and fibrinogen (2,080 versus 440 ng/mL). Smokers with bronchitis showed a trend for a higher neutrophil count and levels of albumin and fibrinogen than healthy subjects. The proportion of sputum eosinophils correlated positively with ECP, MBP, EDN, albumin and fibrinogen levels, and metachromatic cell counts correlated with tryptase. In asthmatics, IL-5 correlated with eosinophil counts. There was a significant negative correlation between sputum indices and expiratory flows and methacholine PC20. Thus, the methods of measuring cell and fluid phase markers in induced sputum used in this study are reproducible and valid. They can therefore be used to reliably measure these indices of airway inflammation.

Measurement of inflammatory indices in induced sputum: effects of selection of sputum to minimize salivary contamination

Sputum examination is being used increasingly as a noninvasive method to assess airway inflammation. Expectorated sputum has variable contamination with saliva. Methods of processing have included the selection of portions of the sample considered to be representative of pulmonary origin versus use of the whole specimen, which is confounded by varying volumes of saliva. We compared cell profiles and eosinophilic cationic protein (ECP) concentration in sputum selected from the expectorate and in the usually discarded residual portion to determine to what degree salivary contamination is minimized and if the results are representative of lower respiratory secretions. Sputum was induced with hypertonic saline in six healthy and nine asthmatic subjects. All portions considered to be of pure lower respiratory tract origin were selected from the residual. The selected and residual portions were treated with dithiothreitol, total cell counts and cell viability were obtained, cytospins were made for differential cell counts and supernatant was collected for ECP assay. Selected portions of the specimens, in comparison with the residual portion showed: little squamous cell contamination (median 1.2 vs 70%; p < 0.001); higher total cell counts.mL-1 (5.1 vs 0.5 x 10(6) cells.mL-1; p < 0.001); higher number of viable nonsquamous cells per sample (1.9 vs 0.6 x 10(6) cells; p < 0.001); higher slide quality score (7 vs 4; p < 0.001); and higher levels of ECP (768 vs 136 micrograms.L-1; p < 0.001). There were no differences in the differential cell counts of eosinophils (1.3 vs 3.8%), neutrophils (44 vs 32%), and lymphocytes (0.6 vs 0.6%). While the proportion of macrophages was lower (36 vs 54%; p < 0.05), the absolute number (41 vs 19 x 10(4) cells; p < 0.05) was higher in the selected portion. In summary, selection of all portions of induced sputum from the expectorate minimized the confounding influence of saliva. Loss of nonsquamous cells in the residual portion was variable but usually less than one third of those in the selected portion. With one exception, this loss had little influence on the differential counts of inflammatory cells. Similar observations apply to eosinophilic cationic protein levels. We conclude that, in healthy subjects and treated asthmatics, inflammatory markers in the selected portion of the expectorate can be used to represent those in the lower respiratory tract in general.

GM-CSF, IL-8, IL-1R, TNF-alpha R, and HLA-DR in nasal epithelial cells in allergic rhinitis

Epithelial cells potentially contribute to airways inflammation by antigen presentation and the production of proinflammatory cytokines. This study investigated the immunocytochemical localization of interleukin-8 (IL-8), granulocyte-macrophage colony-stimulating factor (GM-CSF), interleukin-1 receptor (IL-1R Type I), tumor necrosis factor-alpha receptor (TNF-alpha R; 55kD), and human leukocyte antigen-DR (HLA-DR) on epithelial cells obtained by nasal brushing from 10 patients with allergic rhinitis in season and 15 healthy, nonallergic subjects. Six of the 15 nonallergic asymptomatic subjects had macroscopic evidence of nasal mucosal inflammation, and their brushings contained more than 10% neutrophils ("subclinical inflammation"). In normal control subjects, 8 +/- 7.5% of epithelial cells stained for HLA-DR, approximately one quarter stained for IL-8 and GM-CSF, and about one third stained positive for IL-1R and TNF-alpha R. The findings in subjects with allergic rhinitis in season and with subclinical neutrophilia were similar, and the numbers of cells staining for HLA-DR expression correlated with both neutrophil and lymphocyte content. These findings further support the conclusion that epithelial cells can contribute to inflammatory processes in the nasal mucosa. The findings emphasize the need to identify asymptomatic nasal mucosal inflammation in studies of the nasal mucosa.

CD40 expression by human peripheral blood eosinophils

In this study, we have investigated CD40 expression in human peripheral blood eosinophils and in human chronically inflamed nasal tissues, i.e., nasal polyps. We show by both reverse transcriptase-PCR and Northern blot analysis that eosinophils from allergic subjects express human CD40 mRNA. We also show that constitutive CD40 mRNA expression in eosinophils could be upregulated by exposure to IgA immune complexes and downregulated by IL-10 and the synthetic steroid budesonide. In addition, we demonstrate that eosinophils express CD40 protein by flow cytometry. Such expression is biologically functional as cross-linking CD40 with CD40 mAbs enhances eosinophil survival in a dose-dependent fashion; in addition, CD40 ligation stimulates eosinophils to release GM-CSF. CD40-mediated eosinophil survival was largely inhibited by an anti-GM-CSF neutralizing antibody suggesting GM-CSF involvement in the survival enhancing mechanism. CD40 mRNA was also detected in total RNA extracted from nasal polyp tissues but not in RNA isolated from normal nasal mucosa (inferior turbinate); by immunohistochemistry, we were able to detect immunoreactive CD40 protein in a variety of cell types in the polyp stroma, but primarily in eosinophils. These observations suggest previously unforeseen interactions between eosinophils and cells expressing the CD40 ligand and, thus, novel pathways by which eosinophils may contribute to the regulation of airway inflammation.

Effect of salmeterol compared with beclomethasone on allergen-induced asthmatic and inflammatory responses

Salmeterol is a selective long-acting beta 2-agonist bronchodilator considered to have added anti-inflammatory effects, but this is controversial. We investigated the effects of a single dose of salmeterol, 100 micrograms, on the physiological and inflammatory responses to inhaled allergen and compared these with the effects of a single dose of beclomethasone, 500 micrograms, and of placebo. Eight atopic adults with mild stable asthma, treated only with inhaled short-acting beta 2-agonist when needed, attended the laboratory sequentially for screening tests, two single-blind control inhalation tests preceded 30 min by placebo or salmeterol and three allergen inhalation tests preceded by placebo, salmeterol or beclomethasone double-blind in random order. Airway responsiveness to methacholine (assessed as the provocative concentration of methacholine producing 20% fall in forced expiratory volume in one second (PC20)), induced sputum eosinophils, blood eosinophils and serum eosinophil cationic protein (ECP) were examined before and 7-48 h after treatment. The statistical power to detect twofold changes in blood and sputum parameters was > or = 90%. Salmeterol inhaled before allergen challenge completely prevented the early asthmatic response, late asthmatic response and fall in methacholine PC20 at 24 h, and produced additional bronchodilatation. These effects were similar to those obtained by the inhalation of a single dose of salmeterol before the control inhalation test, and significantly better than those observed after a single dose of beclomethasone inhaled before the allergen test. Beclomethasone had no effect on the early asthmatic response or on the fall in methacholine PC20 at 24 h but partially inhibited the late asthmatic response. Neither salmeterol nor beclomethasone had any significant effect on sputum or blood inflammatory changes 7-48 h after allergen inhalation. In conclusion, whilst salmeterol had no demonstrable anti-inflammatory action in sputum after allergen challenge in asthma, neither did a single dose of the positive anti-inflammatory control, beclomethasone. The latter result excludes a more positive judgement on the possible anti-inflammatory action of salmeterol. However, the results do indicate that potent functional effects of a single dose of salmeterol can mask the airway inflammatory cell influx caused by inhaled allergen.

Intranasal fluticasone propionate versus loratadine in the treatment of adolescent patients with seasonal allergic rhinitis

Fluticasone propionate (FP) is a topical corticosteroid with minimal systemic activity. We examined safety and compared the efficacy of FP aqueous nasal spray, 200 micrograms every day with loratadine tablets, 10 mg by mouth every day in 240 adolescents with ragweed pollen-induced seasonal allergic rhinitis for 4 weeks in a randomized, double-blind, parallel-group study. Nasal and eye symptoms were recorded daily on a 4-point (0 to 3) scale. A higher percentage of symptom-free days was observed for nasal blockage on waking during treatment with FP (p < 0.0001). Significant results were also obtained for all other nasal symptoms when analyzed for both symptom-free days and symptom scores. No differences were found for eye irritation symptoms (p = 0.14). Morning and evening nasal peak inspiratory flow (PIF) was recorded daily by 57 subjects. FP treatment was associated wit significantly higher PIF values than loratadine both morning (p = 0.0051) and evening (p = 0.0036). A greater improvement over 4 weeks was observed for PIF morning values in the FP group (p = 0.008) but not for evening values (p = 0.358). Statistically significant correlations were found for nasal blockage and PIF in the morning (r = -0.54, p = 0.0001) and in the evening (r = -0.46, p = 0.008).

Elevated B cells in sputum of asthmatics. Close correlation with eosinophils

Sputum examination is a useful noninvasive method to study airway inflammation. We investigated the reproducibility and validity of the measurements of lymphocyte subsets in the sputum of 11 stable patients with asthma and 10 nonasthmatic smokers. Sputum was dispersed with 0.1% dithiothreitol. A differential cell count was made with Wright's stain. Aliquots were stained with antibodies to CD19 (B cells), CD3 (T cells), CD4 (helper), CD8 (suppressor), and the activation marker CD25 (IL2 receptor) on T-cell subsets and were assayed by flow cytometry. Sputum from patients with asthma compared with nonasthmatic subjects had more eosinophils (mean +/- SEM, 32.5 +/- 8.5 versus 1.3 +/- 0.5%, p < 0.01) and a higher proportion of lymphocytes that were B cells (16.2 +/- 3.2 versus 4.0 +/- 1.0%, p < 0.01), and these correlated closely with the eosinophils (r = 0.8, p < 0.01). Patients with asthma also had more activated T-helper cells (39.3 +/- 4.6 versus 9.0 +/- 9.0%, p = 0.05), but the comparison was limited to two smokers because of macrophage autofluorescence. The repeatability of measurements of helper T-cells (R = 0.94), suppressor T cells (R = 0.88), and activated helper T cells (R = 0.77) was good; repeatability of measurements of T and B cells could not be examined because these were reciprocals of each other. Asthmatic sputum has different lymphocyte profiles than sputum from nonasthmatic smoking control subjects. The results demonstrate a potential importance of antibody-producing lymphocytes in the airway and their relation to sputum eosinophilia in asthma.

Respiratory infections and the autumn increase in asthma morbidity

Unexplained autumn increases in hospital admissions for asthma have been reported in many countries, including the United States, Canada, England and Wales. To investigate the role of infection, the association was tested between hospital admissions for asthma and respiratory infections among preschool children in Metropolitan Toronto, Canada during the period 1981 to 1989. The seasonal pattern in overall hospital utilization was assessed by admissions for nonrespiratory diseases. Time series analysis was used to remove potentially confounding temporal trends and the influence of correlated errors. A fourfold increase in asthma admissions occurred between July and October unaccompanied by similar increases in nonrespiratory admissions. Admissions began increasing during the third week of August, peaked during the third week in September, and slowly decreased during November and December. After adjusting for serial correlation, trends, climate, ambient air pollution and aeroallergens, the seasonal pattern of respiratory infection explained 14% of the variance in asthma admissions. Based on seasonal patterns, respiratory infection is the major identifiable risk factor for the large autumnal increase in asthma admissions.

Eosinophils as a potential source of platelet-derived growth factor B-chain (PDGF-B) in nasal polyposis and bronchial asthma

Tissue remodeling in bronchial tissues from asthmatics as well as in nasal polyp (NP) tissues includes sub-basement membrane deposition of collagen, stromal deposition of extracellular matrix protein, and hypertrophy/hyperplasia of airway smooth muscle cells, which are relevant to the cellular and molecular events induced by platelet-derived growth factor (PDGF). Therefore, we investigated the localization of mRNA and protein of PDGF-B chain (PDGF-B) in NP tissues and bronchial tissues from mild and severe asthmatics by in situ hybridization and immunohistochemistry, respectively. Cells expressing PDGF-B mRNA were found in all nine NP tissues and in bronchial tissues from 2 of 6 normal subjects, 2 of 5 mild asthmatics, and all of 6 severe asthmatics examined. The vast majority of cells expressing PDGF-B mRNA were eosinophils in NP (99.7 +/- 0.2%, mean +/- SD) and asthmatic bronchial tissues (75.0 and 77.8% in mild asthma, and 92.7 +/- 8.1% in severe asthma), but no cells expressing PDGF-B mRNA were eosinophils in normal bronchial tissues. The number of cells expressing the gene in severe asthma tissues (122.3 +/- 32.2/mm2) was similar to that in NP tissues (152.8 +/- 73.9/mm2) and greater than that in mild asthma tissues (4.7 +/- 7.6/mm2, P < 0.01), which was not significantly greater than that in normal bronchial tissues (3.4 +/- 5.2/mm2). Furthermore, we detected immunolocalization of PDGF-B in NP tissues and in asthmatic bronchial tissues. The eosinophils purified from peripheral blood were demonstrated to express PDGF-B gene transcript and immunoreactivity after stimulation with A23187.(ABSTRACT TRUNCATED AT 250 WORDS)

Urticaria from allergy to a purified human anti-Rh antibody preparation

This case presentation describes a young woman who developed generalized urticaria after receiving the human anti-RhD(D) preparation, WinRho, intravenously. Allergy skin tests and the radioallergosorbent test (RAST) for IgE antibodies to the human anti-D immunoglobulin preparation were positive. Further studies using high-pressure liquid chromatography and protein A column chromatography implicated a nonimmunoglobulin low-molecular-weight contaminant. This case report illustrates an allergic reaction to a highly purified human immunoglobulin preparation, and demonstrates approaches to assessment of such a reaction.

Delayed-type hypersensitivity to human gonadotropin: case report

OBJECTIVE

To investigate adverse reactions to hMG preparations in two women in IVF programs.

DESIGN

Two case reports with skin tests for delayed hypersensitivity (DH) to hMG and a biopsy of one delayed reaction.

SETTING

Allergy and infertility clinics in university medical center.

PATIENTS

Two affected patents with a history of local reactions to the injected hMG, one of whom also had fever, and nine control subjects.

INTERVENTIONS

Skin tests and biopsy.

MAIN OUTCOME MEASURES

Delayed hypersensitivity skin response to hMG in affected patients indicated by timing and biopsy results. Negative skin test with the purified hFSH, which was also used in treatment with no adverse effects.

CONCLUSION

Use of the purified preparation avoids DH reaction.

Increased peak flow variability in children with asymptomatic hyperresponsiveness

The relevance of increased methacholine airway responsiveness detected in children with no current or past symptoms of asthma is not known. We wished to determine whether the presence of airway hyperresponsiveness in asymptomatic children is also associated with abnormal variability of peak expiratory flow (PEF). In 12 asymptomatic children with methacholine hyperresponsiveness, we examined the diurnal variation of peak expiratory flow (PEF) and response to inhaled bronchodilator. Twelve asthmatic children with a comparable range of methacholine hyperresponsiveness, and 12 normal children without methacholine responsiveness, were used as positive and negative controls. The children were aged 11 (range 9-14) yrs. The mean diurnal variation of PEF in those children with asymptomatic hyperresponsiveness was increased at 9.3%, to a degree comparable to the symptomatic asthmatic children (10.7%), and greater than the normal children (5.7%). Methacholine stimulated airway constriction was associated with symptoms in subjects from each group, indicating that the children were capable of perceiving airway constriction. We conclude that asymptomatic children with methacholine airway hyperresponsiveness have other evidence of mild variable airflow obstruction with increased diurnal PEF variability, and can perceive airflow limitation. The lack of symptoms in the children with airway hyperresponsiveness could be due to an insufficient stimulus to cause symptomatic obstruction, or the absence of eosinophilic airway inflammation, which may be a requirement for the development of symptomatic airway hyperresponsiveness.

Exacerbations of asthma without sputum eosinophilia

BACKGROUND

Sputum analysis provides a non-invasive method of examining the airway secretions of subjects with asthma in order to better understand the inflammatory process. Increased proportions of eosinophils are generally seen in the sputum of subjects with asthma, especially when there is an exacerbation. An unexpected observation in the sputum of subjects with mild exacerbations of asthma is reported.

METHODS

Thirty four consecutive subjects with symptoms consistent with a mild exacerbation of asthma were recruited for a treatment study. Inclusion criteria required persistent symptoms of chest tightness, dyspnoea, or wheezing for two weeks (without spontaneous improvement or alteration in dose of inhaled corticosteroid) and a forced expiratory volume in one second (FEV1) that was reversible to more than 75% predicted or known best to ensure the exacerbation was mild. Sputum (spontaneous or induced with hypertonic saline) from all subjects was examined for differential cell counts. Eosinophilic sputum was defined as > or = 4% eosinophils on two occasions or > 10% eosinophils once. Clinical characteristics, sputum differential counts, and measurements of airways obstruction were compared between the subjects with and without sputum eosinophilia.

RESULTS

Almost half of the subjects (16 of 34) considered to have mildly uncontrolled asthma had no sputum eosinophilia. In comparison with the subjects who had sputum eosinophilia the non-eosinophilic group had less airways obstruction (FEV1% predicted 88% v 70%) and less severe airways hyperresponsiveness (PC20 methacholine 0.45 mg/ml v 0.13 mg/ml). There was no difference between the groups in the type or prevalence of symptoms, history of recent infections, smoking, relevant allergen exposure, or use of inhaled corticosteroid.

CONCLUSIONS

Symptoms of mildly uncontrolled asthma are not always associated with eosinophilic airways inflammation as measured by sputum analysis. The causes and treatment of the non-eosinophilic condition require further investigation.

Distinct immunohistochemical localization of IL-4 in human inflamed airway tissues. IL-4 is localized to eosinophils in vivo and is released by peripheral blood eosinophils

Nasal polyposis and asthma are inflammatory conditions of the airways characterized by infiltration of activated inflammatory cells, particularly eosinophils. IL-4 is a multifunctional cytokine considered to play an important role in eosinophilic inflammation. We examined the cellular distribution of immunoreactive IL-4 in nasal polyps, as well as in the bronchial mucosa of both nonasthmatic control subjects (n = 6) and patients with well-characterized mild asthma (n = 6) subjected to a diluent or an allergen challenge. To determine eosinophilic contribution, tissue sections were counterstained with FITC after IL-4 immunostaining. No eosinophils were observed in the bronchial mucosa of nonasthmatic subjects. Nasal polyp tissues contained approximately 15 times more eosinophils per mm2 compared with bronchial tissues from asthmatics after a diluent challenge. Allergen challenge resulted in a marked increase in eosinophil density in bronchial tissues. A negligible number of cells immunostaining IL-4 was observed in bronchial tissues from nonasthmatic control subjects. The density of IL-4-positive cells in nasal polyp tissues was almost three times greater compared with asthmatics bronchial tissues after a diluent challenge. Approximately 90% of the IL-4-positive cells in bronchial tissues did not exhibit fluorescence after FITC counterstaining; in contrast, about 80% of the IL-4-positive cells in nasal polyp tissues did. We also show that peripheral blood eosinophils from allergic subjects express IL-4 mRNA by Northern blot analysis, particularly on stimulation with secretory IgA immune complexes. Finally, the supernatant of stimulated eosinophils contained approximately 50 pg/10(6) cells of IL-4 as determined by ELISA. These data demonstrate that eosinophils express the message and release IL-4 in vitro, and that these cells are the primary source of immunoreactive IL-4 in tissues undergoing chronic severe mucosal inflammation.

Distinct immunohistochemical localization of IL-4 in human inflamed airway tissues. IL-4 is localized to eosinophils in vivo and is released by peripheral blood eosinophils

Nasal polyposis and asthma are inflammatory conditions of the airways characterized by infiltration of activated inflammatory cells, particularly eosinophils. IL-4 is a multifunctional cytokine considered to play an important role in eosinophilic inflammation. We examined the cellular distribution of immunoreactive IL-4 in nasal polyps, as well as in the bronchial mucosa of both nonasthmatic control subjects (n = 6) and patients with well-characterized mild asthma (n = 6) subjected to a diluent or an allergen challenge. To determine eosinophilic contribution, tissue sections were counterstained with FITC after IL-4 immunostaining. No eosinophils were observed in the bronchial mucosa of nonasthmatic subjects. Nasal polyp tissues contained approximately 15 times more eosinophils per mm2 compared with bronchial tissues from asthmatics after a diluent challenge. Allergen challenge resulted in a marked increase in eosinophil density in bronchial tissues. A negligible number of cells immunostaining IL-4 was observed in bronchial tissues from nonasthmatic control subjects. The density of IL-4-positive cells in nasal polyp tissues was almost three times greater compared with asthmatics bronchial tissues after a diluent challenge. Approximately 90% of the IL-4-positive cells in bronchial tissues did not exhibit fluorescence after FITC counterstaining; in contrast, about 80% of the IL-4-positive cells in nasal polyp tissues did. We also show that peripheral blood eosinophils from allergic subjects express IL-4 mRNA by Northern blot analysis, particularly on stimulation with secretory IgA immune complexes. Finally, the supernatant of stimulated eosinophils contained approximately 50 pg/10(6) cells of IL-4 as determined by ELISA. These data demonstrate that eosinophils express the message and release IL-4 in vitro, and that these cells are the primary source of immunoreactive IL-4 in tissues undergoing chronic severe mucosal inflammation.

Anaphylaxis to carrageenan: a pseudo-latex allergy

BACKGROUND

Anaphylactic reactions during a barium enema have been attributed to allergy to latex on the barium enema device. The observation of anaphylaxis during barium enema without latex exposure or latex allergy led to the performance of an allergy skin test to the barium enema solution.

METHODS

Individual components of the barium enema solution were obtained for double-blind skin testing. A RAST to identify specific IgE antibodies to the skin test active agent was established.

RESULTS

Carrageenan, a component of the barium enema solution, produced positive reactions to allergy skin test and RAST. Gastrointestinal symptoms for which the patient was being investigated by the barium enema subsequently disappeared with a diet free of carrageenan.

CONCLUSIONS

Carrageenan is a previously unreported cause of anaphylaxis during barium enema. It is an allergen widely distributed in common foods and potentially could account for some symptoms related to milk products or baby formula.

Some technical factors influencing the induction of sputum for cell analysis

Inhalation of hypertonic saline aerosol is a relatively noninvasive method to obtain sputum for examination of inflammatory processes in the airways. We investigated some technical factors which might influence the success of induction and sputum cell counts. In total, twenty six asthmatic and 13 healthy subjects, unable to raise sputum spontaneously, inhaled nebulized saline for three 7 min intervals. In three randomized, cross-over studies we repeated sputum induction on separate days with two ultrasonic nebulizers (De Vilbiss Ultraneb 99 and Fisoneb) and one jet nebulizer (Pari LL with Master Compressor) (Study 1, n = 15), with different saline concentrations (normal saline 0.9%; hypertonic saline 3% on 2 days; and hypertonic saline 3, 4 and 5%, sequentially) (Study 2, n = 14) and with pretreatment with either salbutamol or placebo (Study 3, n = 10). The latter two studies were double-blind. Sputum cells were dispersed with dithiothreitol, and the cell suspension was used to perform total cell counts and to prepare cytospins for differential cell counts. We compared success rate, cell counts, subject discomfort and percentage fall in forced expiratory volume in one second (FEV1) during the procedures. All sputum examinations were performed blind to the clinical procedures. The success rates and the cell counts of the specimens obtained with the two ultrasonic nebulizers were not different, whilst general discomfort was proportional to the saline output of the nebulizer. Induction of sputum by hypertonic saline was more successful than normal saline, but more disagreeable to the subjects. Induction with saline 3% on two days was only successful in 6 of 14 subjects.(ABSTRACT TRUNCATED AT 250 WORDS)

Some technical factors influencing the induction of sputum for cell analysis

Inhalation of hypertonic saline aerosol is a relatively noninvasive method to obtain sputum for examination of inflammatory processes in the airways. We investigated some technical factors which might influence the success of induction and sputum cell counts. In total, twenty six asthmatic and 13 healthy subjects, unable to raise sputum spontaneously, inhaled nebulized saline for three 7 min intervals. In three randomized, cross-over studies we repeated sputum induction on separate days with two ultrasonic nebulizers (De Vilbiss Ultraneb 99 and Fisoneb) and one jet nebulizer (Pari LL with Master Compressor) (Study 1, n = 15), with different saline concentrations (normal saline 0.9%; hypertonic saline 3% on 2 days; and hypertonic saline 3, 4 and 5%, sequentially) (Study 2, n = 14) and with pretreatment with either salbutamol or placebo (Study 3, n = 10). The latter two studies were double-blind. Sputum cells were dispersed with dithiothreitol, and the cell suspension was used to perform total cell counts and to prepare cytospins for differential cell counts. We compared success rate, cell counts, subject discomfort and percentage fall in forced expiratory volume in one second (FEV1) during the procedures. All sputum examinations were performed blind to the clinical procedures. The success rates and the cell counts of the specimens obtained with the two ultrasonic nebulizers were not different, whilst general discomfort was proportional to the saline output of the nebulizer. Induction of sputum by hypertonic saline was more successful than normal saline, but more disagreeable to the subjects. Induction with saline 3% on two days was only successful in 6 of 14 subjects.(ABSTRACT TRUNCATED AT 250 WORDS)

Chronic cough with eosinophilic bronchitis: examination for variable airflow obstruction and response to corticosteroid

The purpose of this study was to examine airway responsiveness, sputum cells and the effects of inhaled corticosteroid in the chronic cough syndrome associated with eosinophilic bronchitis. We studied nine consecutive referrals with chronic cough, sputum with > 10% eosinophils, normal spirometry, and normal methacholine airway responsiveness. Clinical assessment, sputum analysis, allergy skin tests and a methacholine inhalation test were performed at the first visit. Peak expiratory flow (PEF) was measured twice daily for 1 week followed by an adenosine monophosphate (AMP) inhalation test. Subjects were then treated with inhaled beclomethasone 0.4 mg twice daily for 7 days. Sputum analysis and measurement of methacholine responsiveness were then repeated. Excessive airway narrowing to methacholine was not present in any of the subjects. A methacholine plateau response was present in five subjects. Hyperresponsiveness to AMP was absent in six of the nine subjects, and PEF variability was not increased for eight subjects. Corticosteroid therapy led to a reduction in sputum eosinophil counts from 40.1 (SD 21.4)% to 4.0 (4.5)% but there was no significant change in metachromatic cell counts (0.8 SD 0.5% vs 0.6 SD 0.6%) or total cell counts. Methacholine responsiveness improved within the normal range in the three subjects in whom it could be determined. Chronic cough associated with eosinophilic airway inflammation can occur in the absence of variable airflow obstruction (asthma) and can improve after treatment with inhaled corticosteroid. This treatment can reduce the level of methacholine responsiveness within the normal range and reduces sputum eosinophils but not mast cells.(ABSTRACT TRUNCATED AT 250 WORDS)

Nasal polyp inflammation. Effect of topical nasal steroid

Topical nasal corticosteroid therapy produces clinical improvement in patients with nasal polyposis. To examine the mechanisms of steroid effect, we quantified the number of inflammatory cell types as well as the expression of relevant cell markers in nasal polyps from steroid treated patients (n = 11) and polyps from untreated patients (n = 10) judged to require polypectomy for symptomatic relief. We found that the majority of eosinophils in these tissues were in the stromal layers, and that the proportion of activated eosinophils (EG2+ versus total eosinophil count) was significantly lower in polyps from patients treated with the topical nasal steroid budesonide, 200 to 400 micrograms/d for 1 mo, than in polyps from untreated patients. We also found that in polyps from treated patients, the superficial stromal layer (SSL) and deep stromal layer (DSL) both contained a significantly lower tissue density of lymphocytes of CD3, CD4, and CD8 subsets. Treatment was also associated with a lower, albeit nonsignificant, expression of ICAM-1 and HLA-DR in the epithelium. The tissue density of CD14+ cells (monocyte/macrophage) and of tryptase+ cells (mast cells) was the same in the two groups. These findings demonstrate tissue effects of topical corticosteroid treatment which may point to the mechanisms of therapeutic benefit. In addition, these observations illustrate the value of markers that indicate cell functional activity rather than just cell numbers.

Efficacy of loratadine versus placebo in the prophylactic treatment of seasonal allergic rhinitis

The efficacy of loratadine as prophylactic therapy for seasonal allergic rhinitis was evaluated in a randomized, double-blind, parallel group, placebo-controlled study. One hundred eighteen subjects received either loratadine, 10 mg once daily, or placebo for 6 weeks. Treatment was begun prior to the onset of grass pollen seasonal symptoms of allergic rhinitis. Total symptom-free days occurred more frequently in subjects receiving loratadine. More loratadine than placebo subjects (65% versus 49%) had no symptoms or mild rhinitis at the end of the study. In contrast, the differences between loratadine and placebo in symptom scores did not achieve significance. The incidence of sedation and anticholinergic effects were comparable between the groups. Prophylactic loratadine therapy was effective in suppressing symptoms of seasonal allergic rhinitis and providing patients with symptom-free days throughout the pollen season.

TNF-alpha production by eosinophils in upper airways inflammation (nasal polyposis)

TNF-alpha is a cytokine with a wide spectrum of proinflammatory activities. Nasal polyps (NP), which occur in association with allergic rhinitis and asthma, are characterized by a marked infiltration of activated eosinophils, epithelial damage, and varying degrees of stromal fibrosis. By using Southern blot analysis after a reverse transcription-PCR, we detected a signal specific for TNF-alpha mRNA in five of seven NP samples, but not in control nasal mucosal samples. With in situ hybridization, we detected cells expressing mRNA specific for TNF-alpha in eight of thirteen NP samples, but not in four control samples. Counterstaining with chromotrope 2R demonstrated that virtually all cells expressing TNF-alpha message were eosinophils. The ratio of eosinophils expressing TNF-alpha to the total number of eosinophils varied greatly among tissues; as an average, we observed 24% TNF-alpha-positive eosinophils. Using a mAb against human TNF-alpha, we demonstrated TNF-alpha localization in 12 NP tissues (48.8 +/- 16.5 positive cells/mm2) but not in three control samples. Morphologically, cells localizing TNF-alpha were both mononucleated and polynucleated with only a small number of eosinophils, as determined by aniline blue counterstaining. Studies of purified blood eosinophils from a patient with hypereosinophilic syndrome and from four healthy donors indicated that TNF-alpha is produced, but rapidly secreted, so that TNF-alpha mRNA-positive cells contain little detectable protein. Furthermore, cells that retain detectable TNF-alpha may not contain sufficient TNF-alpha mRNA to be detected by using the probe developed for our studies. Together, these findings identify a novel mechanism by which eosinophils may contribute to mucosal inflammation and provide an approach to future investigation.

TNF-alpha production by eosinophils in upper airways inflammation (nasal polyposis)

TNF-alpha is a cytokine with a wide spectrum of proinflammatory activities. Nasal polyps (NP), which occur in association with allergic rhinitis and asthma, are characterized by a marked infiltration of activated eosinophils, epithelial damage, and varying degrees of stromal fibrosis. By using Southern blot analysis after a reverse transcription-PCR, we detected a signal specific for TNF-alpha mRNA in five of seven NP samples, but not in control nasal mucosal samples. With in situ hybridization, we detected cells expressing mRNA specific for TNF-alpha in eight of thirteen NP samples, but not in four control samples. Counterstaining with chromotrope 2R demonstrated that virtually all cells expressing TNF-alpha message were eosinophils. The ratio of eosinophils expressing TNF-alpha to the total number of eosinophils varied greatly among tissues; as an average, we observed 24% TNF-alpha-positive eosinophils. Using a mAb against human TNF-alpha, we demonstrated TNF-alpha localization in 12 NP tissues (48.8 +/- 16.5 positive cells/mm2) but not in three control samples. Morphologically, cells localizing TNF-alpha were both mononucleated and polynucleated with only a small number of eosinophils, as determined by aniline blue counterstaining. Studies of purified blood eosinophils from a patient with hypereosinophilic syndrome and from four healthy donors indicated that TNF-alpha is produced, but rapidly secreted, so that TNF-alpha mRNA-positive cells contain little detectable protein. Furthermore, cells that retain detectable TNF-alpha may not contain sufficient TNF-alpha mRNA to be detected by using the probe developed for our studies. Together, these findings identify a novel mechanism by which eosinophils may contribute to mucosal inflammation and provide an approach to future investigation.