Monitoring sputum eosinophils in mucosal inflammation and remodelling: a pilot study.

Normalisation of eosinophil counts in sputum of asthmatic patients reduces eosinophilic exacerbations. However, the effect of this strategy on airway remodelling remains to be determined. We compared bronchial inflammation and collagen deposition after 2 yrs of treatment guided by either sputum eosinophils (sputum strategy, SS) or by clinical criteria (clinical strategy, CS). As a pilot study, 20 mild asthmatic patients were randomly assigned to CS or SS strategies. Bronchial biopsies were obtained when minimum treatment needed to maintain control was identified and this was continued for 2 yrs. Biopsies were immunostained for inflammatory cells, mucin 5A (MUC5A) and collagen. The mean dose of inhaled corticosteroids at the start and end of the study was similar in both SS and CS groups. Forced expiratory volume in 1 s increased in both groups at the study end. In SS, mucosal lymphocyte and eosinophil counts, but not neutrophils, were reduced at the end of the study. In CS, only activated eosinophil and neutrophil counts decreased. MUC5A staining decreased in SS but not CS. No change in collagen deposition underneath the basement membrane was observed in either strategy. Treatment strategies that normalise sputum eosinophils also reduce mucosal inflammatory cells and MUC5A expression, but do not change subepithelial collagen deposition in mild to moderate asthma.

Stable COPD: predicting benefit from high-dose inhaled corticosteroid treatment.

The role of inhaled corticosteroids in the management of chronic obstructive pulmonary disease (COPD) remains controversial. The purpose of this study was to evaluate whether sputum eosinophilia (defined as eosinophils > or = 3%) predicts clinical benefit from inhaled corticosteroid treatment in patients with smoking-related clinically stable moderate-to-severe COPD. Forty consecutive patients with effort dyspnoea (mean age 67 yrs; 52 pack-yr smoking history; post-bronchodilator forced expiratory volume in one second (FEV1) <60% predicted, consistent with moderate-to-severe smoking-related chronic airflow limitation) were enrolled. Subjects were treated with inhaled placebo followed by inhaled budesonide (Pulmicort Turbuhaler 1,600 microg.day(-1)), each given for 4 weeks. While the treatment was single-blind (subject level), sputum cell counts before and after treatment interventions were double-blind, thus removing bias. Outcome variables included spirometry, quality-of-life assessment and 6-min walk test. Sputum eosinophilia was present in 38% of subjects. In these, budesonide treatment normalised the eosinophil counts and, in comparison to placebo treatment, resulted in clinically significant improvement in the dyspnoea domain of the disease-specific chronic respiratory questionnaire (0.8 versus 0.3) and a small but statistically significant improvement in post-bronchodilator spirometry (FEV1 100 mL versus 0 mL; p<0.05). In conclusion, sputum eosinophilia predicts short-term clinical benefit from high-dose inhaled corticosteroid treatment in patients with stable moderate-to-severe chronic obstructive pulmonary disease.

Failure of montelukast to reduce sputum eosinophilia in high-dose corticosteroid-dependent asthma.

Sputum eosinophilia is a sensitive predictor of benefit from corticosteroid treatment. Montelukast is a cysteinyl leukotriene antagonist, which also reduces sputum and blood eosinophils. The present study examined the possibility that montelukast has an added eosinophil-lowering effect in subjects with asthma who are corticosteroid responsive but relatively corticosteroid resistant. A total of 14 clinically stable adults with asthma requiring minimum treatment with a high-dose inhaled steroid or prednisone, with baseline sputum eosinophilia (> or =5%), were randomised to receive 4 weeks of 10 mg montelukast or placebo daily in a double-blind crossover trial. The primary outcome was the effect of treatment on the percentage of sputum eosinophils. Secondary outcomes were changes in the blood eosinophil count, symptoms, forced expiratory volume in one second, peak expiratory flow and the need for salbutamol. The median (interquartile range, i.e. 75th-25th centile) for sputum eosinophils at baseline was 15.7% (22). The effect of adding montelukast was not significantly different from that of placebo, sputum eosinophils being 9.3% (18.9) after montelukast and 11.3% (22.8) after placebo. No difference was detected on secondary outcomes. No crossover interactions were observed. In conclusion, the addition of montelukast to existing high-dose corticosteroid therapy in subjects with asthma with elevated sputum eosinophils does not provide additional attenuation of airway eosinophilia.

Purine nucleotide catabolism in rat liver: labelling of uric acid and allantoin after treatment with oxonic acid and allopurinol.

In our previous experiments on rat liver we found that 15' after intraperitoneal administration of 14C-formate the specific radioactivity of allantoin was always higher than that of uric acid. The present experiments have been carried out to interpret this unexpected result, which was only observed in liver and we studied: a) the incorporation of 14C-glycine into uric acid and allantoin; b) the effects of two competitive inhibitors of xanthine oxidase and uricase, oxonic acid and allopurinol respectively, on levels of uric acid and allantoin in liver and on their specific radioactivity after administration of labelled precursor. The results suggested: a) that under normal conditions, the formation of allantoin is so fast that it exceedes export from liver to serum, and thus the radioactivity of labelled precursors accumulates in allantoin; b) that when allopurinol or oxonic acid are administered, the rate of export exceeds that of allantoin formation and the incorporation of radioactivity into allantoin is lower; c) that not all the data, however, could be interpreted on this basis, but seems to require the existence of different pools of uric acid, which are transformed separately into allantoin.

Influence of amalgam fillings on Hg levels and total antioxidant activity in plasma of healthy donors.

In order to evaluate the influence of mercury (Hg) levels on antioxidant power in human plasma, 26 healthy people were evaluated by a dentist and their plasma analyzed for Hg content by atomic absorption and total antioxidant activity (TAA) by FRAP method. Hg plasma concentration correlated with number of amalgam restorations, suggesting that Hg released from fillings is a source of Hg in non-occupational exposed people. Fish consumption, in fact, showed no influence on Hg plasma levels, perhaps because Italian subjects examined in the present group used low quantity of fish at week or kinds of fish with light contamination. TAA negatively correlated with Hg plasma revealing a pro-oxidant role of Hg released from amalgam fillings.

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.

Serial sputum cell counts in the management of chronic airflow limitation.

This case study illustrates the usefulness of serial induced sputum cell counts from cytospins to investigate the nature of airway inflammation in a patient presumed to have prednisone-dependent asthma for 30 yrs. She had bronchiectasis and chronic airflow limitation. Exacerbations of breathlessness were associated with an increase in chronic airflow limitation with little or no sputum. Induced sputum showed elevated total cell and neutrophil counts at each exacerbation with no increase in the proportion of eosinophils. Pathogenic bacteria were cultured at each flare-up. The dose of prednisone was reduced progressively and each exacerbation was treated with an appropriate antibiotic without increasing the dose of prednisone, as was the case previously. The infections were associated with bronchiectasis of the right upper lobe which was removed. Examination of the specimen confirmed neutrophilic infiltration and did not show the usual airway structural changes of asthma. These results provide further evidence of the value of sputum cell counts in practice, in this case to prevent overtreatment with prednisone in a patient with recurrent deteriorations in airflow which were due to recurrent infections.

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.

Effect of estradiol on serum triglyceride lipoprotein levels and fatty acid composition in castrated rats.

Triglyceride content and fatty acid composition of rat serum lipoproteins showed specific variations after castration and estradiol treatment. Triglyceride levels decreased in VLDL after castration and in LDL and HDL after low doses of estradiol. High doses of estradiol enhanced triglyceride levels in VLDL and decreased them in LDL. Fatty acid composition showed a complex pattern: after castration, monoenoic acids decreased and essential fatty acids increased in all lipoprotein classes, enhancing the EFA/NEFA and EFA/ME ratios. Both doses of estrogen lowered these ratios in VLDL and LDL, but decreased them in HDL with high doses and enhanced them in HDL with low doses.

Purine nucleotide metabolism: specific aspects in chronic lymphocytic leukemia lymphocytes.

The metabolism of purine nucleotides was studied in human peripheral blood lymphocytes from healthy subjects and patients with B-cell chronic lymphocytic leukemia. Nucleotide content was determined by HPLC. The rate of de novo synthesis of purine nucleotides was measured kinetically by following the incorporation of 14C-formate into the nucleotides of a lymphocyte suspension. The patterns of the main enzymes involved in purine nucleotide metabolism (those of the salvage pathway and catabolism) were estimated by a radiochemical method. Although the data expressed in relation to cells and protein showed some discrepancies, several common differences were evident in both cases. The main differences were an increase in NAD and IMP, a sharp decrease in 5'-nucleotidase activities and in total guanylate content and synthesis, and an increase in the A/G ratio in lymphocytes of patients with respect to controls. The changes in these parameters in CLL indicate an imbalance in purine metabolism and may play a specific role in the biology of the leukemia cell. They are also potential biochemical markers of lymphoid malignancies and may be useful in chemotherapic applications.

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.

Effect of estradiol on phospholipid lipoprotein levels and fatty acid composition in the rat.

Phospholipid content and fatty acid composition in the different serum lipoproteins showed specific variations after castration and estradiol administration. Only the levels of phospholipids in HDL, the principal lipoprotein carrying phospholipids, increased after castration and were further enhanced by estradiol treatment, especially at low doses. Fatty acid composition showed many variations and an irregular pattern. The EFA/NEFA, EFA/ME and SAT/ME ratios were calculated. EFA/ME increased in VLDL after both doses of estradiol, while EFA/NEFA and EFA/ME of LDL enhanced at the low dose and decreased at the high one in a dose-dependent manner. HDL showed higher EFA/ME and SAT/ME ratios after castration and lower values of all ratios after both doses of estradiol. The correlation with diseases more frequent in men is discussed.

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.