Grain dust-induced airflow obstruction and inflammation of the lower respiratory tract

To investigate the relationship between the physiologic and biologic effects of grain dust inhalation, we exposed 15 nonsmoking, nonasthmatic, nonatopic male grain handlers to buffered saline and aqueous corn dust extract by inhalation challenge in a crossover study. The inhalation challenges to buffered saline and corn dust extract were separated by at least 14 d. Compared with buffered saline, inhalation of corn dust extract resulted in significant airflow obstruction, which was observed within 30 min of exposure and persisted for 5 h. Inhalation of corn dust extract resulted in an acute inflammatory response characterized by higher concentrations of neutrophils (p = 0.001), IL-1 beta (p = 0.001), IL-1RA (p = 0.001), IL-6 (p = 0.001), IL-8 (p = 0.001), and TNF-alpha (p = 0.04) in bronchoalveolar lavage (BAL) fluid. mRNA levels specific for IL-1 beta, IL-1RA, IL-6, and IL-8 from cells present in the BAL fluid were significantly greater after challenge with corn dust extract than after challenge with buffered saline. Importantly, no significant differences were observed in the concentration of lymphocytes or eosinophils in the BAL fluid following inhalation of corn dust extract, and the concentrations of histamine and 15-HETE were similar in BAL fluid after the two challenges. The maximal percentage decrease in FEV1 was significantly associated with the absolute neutrophil concentration in the BAL fluid (p = 0.001), as well as the concentration of TNF-alpha (p = 0.03), IL-1 beta (p = 0.005), IL-1RA (p = 0.001), IL-6 (p = 0.001), and IL-8 (p = 0.001) in the BAL fluid.(ABSTRACT TRUNCATED AT 250 WORDS)     

Elevated levels of IL-6, INF-gamma, and TNF-alpha in mice in response to cotton dust are modulated by anti-TNF-alpha antiserum

Acute pulmonary neutrophilic inflammation triggered by cotton dust exposure is one of the features of organic dust syndrome. Studies with a mouse model have reproduced the inflammation and have shown the presence of tumor necrosis factor-alpha (TNF-alpha) in the bronchoalveolar lavage (BAL) fluid of mice following a 3-h exposure to respirable cotton dust particles. A cover glass technique for cytospin samples of BAL cells resulted in a 42-fold increase in cell count, with 76% neutrophils, 13% lymphocytes, and 10% macrophages, after cotton dust exposure. Immunohistochemical staining of lung specimens with anti-TNF-alpha antiserum revealed TNF in the cells surrounding pulmonary airways and vessels. Cotton dust exposure resulted in elevated TNF-alpha, IL-6, and INF-gamma in BAL fluid, INF-gamma and IL-6 in serum. Administration of anti-TNF-alpha antiserum prior to the organic dust exposure resulted in a marked attenuation of the pulmonary inflammatory cell response, as well as decreased IL-6 and TNF-alpha levels in BAL fluid and decreased IL-6 and INF-gamma in serum. These results indicate TNF modulation of the dust-induced toxic alveolitis and cytokine production.     

Inhalation of cold air increases the number of inflammatory cells in the lungs in healthy subjects

Prolonged exposure to cold air may induce a chronic asthma-like condition in healthy subjects as has been demonstrated in cross-country skiers. In the present controlled study, our aim was to elucidate further the link between cold air exposure and airway inflammation by assessing the cellular influx and mediator levels within the airways following acute exposure to cold air. Bronchoalveolar (BAL) and nasal lavages were performed after exposure to cold air (-23 degrees C) and normal indoor air (+22 degrees C) during a light, intermittent work for 2 h in a cross-over design in eight healthy, nonsmoking, subjects. Analyses of inflammatory cell number, cell activation markers, pro-inflammatory cytokines, albumin and interleukin (IL)-8 in lavage fluids were performed. The number of granulocytes and of alveolar macrophages in BAL fluid was significantly higher after cold air exposure (p<0.05). No increase in BAL fluid lymphocytes and no signs of lymphocyte activation in BAL fluid were found. The concentration of IL-8 was unchanged. There were no signs of granulocyte activation (myeloperoxidase, eosinphilic cationic protein) in BAL fluid. Cold air did not influence the number of inflammatory cells or the concentration of albumin and IL-8 in nasal lavage fluid. In conclusion, exposure to cold air induces an increased number of granulocytes and macrophages in the lower airways in healthy subjects without influencing other inflammatory indices such as cellular activation, plasma leakage and pro-inflammatory cytokines. These findings support the hypothesis that cold air could be of pathogenetic importance in the asthma-like condition previously found in cross-country skiers.     

High levels of interleukin-8 in the blood and alveolar spaces of patients with pneumonia and adult respiratory distress syndrome

There is ample experimental evidence that polymorphonuclear neutrophils (PMN) play a critical role in the pathogenesis of the adult respiratory distress syndrome (ARDS). Since interleukin-8 (IL-8) is a strong chemotactic factor for PMN, we measured IL-8 levels in plasma and bronchoalveolar lavage (BAL) fluid of 18 patients, 12 with ARDS and 6 with severe pneumonia uncomplicated by ARDS, all of whom had an increased number of PMN in BAL fluid. Seven healthy subjects served as controls. We found elevated levels of IL-8 in the alveolar spaces of all patients tested. Elevated BAL IL-8 levels were related to a fatal outcome and the presence of shock and correlated with a general clinical severity index (simplified acute physiological score). BAL fluid levels of IL-8 were significantly higher in patients with ARDS than in patients with pneumonia. In plasma, IL-8 levels were increased similarly in all patients and did not correlate with survival or the presence of shock. The BAL fluid-to-plasma ratio of IL-8 was significantly greater than that of tumor necrosis factor alpha, indicating higher local production of IL-8. Moreover, the presence of a primed subpopulation of blood PMN with respect to H2O2 production indicates that IL-8 may contribute to the neutrophil-mediated process in the pathogenesis of ARDS and pneumonia.     

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.     

Oleamide potentiates benzodiazepine-sensitive gamma-aminobutyric acid receptor activity but does not alter minimum alveolar anesthetic concentration

Short-term exposure to ozone at peak ambient levels induces neutrophil influx and impairs lung function in healthy humans. In order to investigate the mechanisms contributing to neutrophil recruitment and to examine the role of T-cells in the acute inflammatory response, we exposed 12 healthy humans to 0.2 parts per million (ppm) of ozone and filtered air on two separate occasions for 2 h with intermittent periods of rest and exercise (minute ventilation = 30 L x min(-1)). Fibreoptic bronchoscopy was performed 6 h after the end of exposures. Total protein, tryptase, histamine, myeloperoxidase, interleukin (IL)-8 and growth-related oncogene-alpha (Gro-alpha) were measured and total and differential cell counts were performed in bronchoalveolar lavage (BAL) fluid. Flow cytometry was performed on BAL cells to study total T-cells, T-cell receptors (alphabeta and gammadelta), T-cell subsets (CD4+ and CD8+ cells) and activated T-cell subsets (CD25+). Using immunohistochemistry, neutrophils, mast cells, total T-cell numbers, T-cell subsets, CD25+ T-cells and leukocyte endothelial adhesion molecules including P-selectin, E-selectin, intercellular adhesion molecule (ICAM)-1 and vascular adhesion molecule (VCAM)-1 were quantified in the bronchial biopsies. Paired samples were available from nine subjects. Following ozone exposure there was a threefold increase in the proportion of polymorphonuclear neutrophils (PMNs) (p=0.07) and epithelial cells (p=0.05) in BAL fluid. This was accompanied by increased concentrations of IL-8 (p=0.01), Gro-alpha (p=0.05) and total protein (p=0.058). A significant positive correlation was demonstrated between the two chemokines and proportion of PMNs in BAL fluid. After ozone exposure there was a significant decrease in the CD4/CD8 ratio (p=0.05) and the proportion of activated CD4+ (p=0.01) and CD8+ T-cells (p=0.04). However, no significant changes were demonstrable in any of the inflammatory markers studied in the biopsies. Short-term exposure of healthy humans to 0.2 ppm ozone induced a neutrophil influx in peripheral airways at 6 h post exposure, but no apparent inflammatory response in proximal airways. This response seems to be mediated at least in part by interleukin-8 and growth-related oncogene-alpha.     

TRFK-5 reverses established airway eosinophilia but not established hyperresponsiveness in a murine model of chronic asthma

We studied the effects of an anti-interleukin (IL)-5 monoclonal antibody (TRFK-5) or dexamethasone (DEX) to reverse already established airway hyperresponsiveness (AHR) and tissue eosinophilia in a Schistosoma mansoni antigen-sensitized and airway-challenged mouse model of chronic asthma. In this model at 4 d after antigen challenge there is dramatic bronchoalveolar lavage fluid (BAL) eosinophilia, AHR to intravenous methacholine (MCh), and histologic evidence of peribronchial eosinophilic infiltration and mucoid cell hyperplasia. These changes persist for up to 2 wk after antigen challenge. Treatment with DEX from Days 4 through 10 significantly reduced established airway eosinophilia compared with animals sham-treated with saline from Days 4 -10 (120 +/- 29 eosinophils/microl BAL for DEX-treated mice versus 382 +/- 60 eosinophils/microl BAL for sham-treated animals, p < 0.01). DEX-treated mice also had dramatically reduced mucoid cell hyperplasia, and airway responsiveness returned to normal. In contrast, TRFK-5 given during the same time period reduced airway eosinophilia (86 +/- 32 eosinophils/microl BAL versus 382 +/- 60 eosinophils/microl BAL, p < 0.01) but did not reduce goblet cell hyperplasia or reverse already established AHR. Treatment with DEX but not TRFK-5 also inhibited interferon gamma (IFN-gamma) content of BAL fluid (0.49 +/- 0.09 ng/ml BAL fluid for DEX versus 1.50 +/- 0.24 ng/ml BAL fluid and 1.36 +/- 0.13 ng/ml BAL fluid for TRFK-5 and sham-treated mice, respectively, both p < 0.001 versus DEX). Thus, treatment with DEX reduces established eosinophilic airway inflammation and AHR in S. mansoni-sensitized and airway-challenged mice but treatment with TRFK-5 reversed established eosinophilia without ameliorating established AHR. Together, these data suggest that once airway inflammation develops, neutralizing the effects of IL-5 or reducing eosinophilia alone may not result in inhibiting established AHR in atopic asthma.     

The action of 5-fluorouracil on human HT29 colon cancer cells grown in SCID mice: mitosis, apoptosis and cell differentiation

BACKGROUND: The effect of oxygen toxicity in human airways is still poorly documented. We prospectively evaluated the inflammatory reaction induced by nasal oxygen exposure in an experimental setting. METHODS: Healthy subjects without nasal symptoms were exposed to high FIO2 during 5 h. Oxygen was delivered from a tank at a flow of 4 l/min to one nostril of each subject and both nostrils were studied. Mucociliary clearance was measured as saccharine nasal transit time (SNTT). Nasal lavage was performed with 5 ml normal saline and the fluid recovered was processed for cytology and measurements of cytokines concentrations: TNF alpha, IL-6, IL-8 and soluble ICAM-1. Under local anaesthesia, biopsies were performed for immunochemistry and electron microscopy. RESULTS: After oxygen exposure mucociliary clearance decreased and SNTT increased from 16 [9-21] to 20.5 [14-32] min (median and extremes; P < 0.1). In the lavage fluid, concentration of IL-6 was higher in the oxygen-exposed nostril (40.5 [11-128] pg/ml) than in the non-exposed one (7 [0-34] pg/ml; P < 0.05). There was also a trend for a higher IL-8 in the exposed than in the non-exposed nostril, (respectively 501 [214-587] pg/ml and 214 [122-616] pg/ml, P < 0.08), and for a higher number of polymorphonuclear cells in exposed nostril. In the mucosal biopsies substance P was not found, but ICAM-1 expression was higher in the mucosa and submucosa of the exposed nostrils where mast cells were also more abundant and showed piecemeal degranulation. CONCLUSION: In summary, we found clinical, functional and biological evidence of ongoing nasal inflammation following high FIO2 inhalation for 5 h. Since the histology and behaviour of nasal and bronchi mucosa are very similar, the same inflammatory events are likely to be occurring in the bronchi upon high concentrations of inhaled oxygen.     

Nasal symptoms and indices of nasal inflammation in flour-dust-exposed bakers

OBJECTIVE: To analyze whether indices of nasal airway inflammation in bakers were related to nasal symptoms and exposure to airborne flour dust. METHODS: A cross-sectional study was performed in 12 currently flour-exposed bakers. They were examined by nasal lavage (NAL), visual inspection, a test of mucociliary clearance, and nasal peak expiratory flow (nasal PEF). NAL fluid was analyzed according to the inflammatory markers eosinophil cationic protein (ECP), indicating eosinophilic activity; myeloperoxidase (MPO), indicating active neutrophils; hyaluronic acid (HA) from active fibroblasts; tryptase, indicating activation of mast cells; and albumin, indicating plasma exudation. The bakers were also questioned about respiratory symptoms and working history. Their current and cumulative exposure to inhalable flour dust was estimated after exposure measurements and information about earlier work tasks. Office workers (n=16) without occupational exposure to dust or any other known nasal irritant or sensitizer served as controls. RESULTS: Personal inhalable dust measurements among the bakers working as dough makers or bread formers ranged from 1.0 to 3.8 mg/m3. Of the 12 bakers, 10 reported at least 1 nasal symptom (crusts, blockage, or a runny nose), a proportion significantly greater than that of the controls (P=0.009). Bakers with nasal symptoms had higher concentrations of markers of inflammation in their NALs as compared with nonsymptomatic bakers. The difference was significant for MPO (P=0.02) and HA (P=0.04) in relation to a runny nose. Tryptase was detected in only one NAL of the bakers. There was a positive correlation between the cumulative dose of inhalable flour dust and concentrations of MPO and HA in NAL. Two bakers were sensitized to wheat; they had the highest NAL concentrations of inflammatory markers. CONCLUSIONS: Our results indicate that flour dust exposure in bakers at levels below the current occupational exposure limit causes nasal mucosal inflammation, which, in turn, is related to nasal symptoms. We propose that the inflammation may be nonallergic, characterized by activation of neutrophils and fibroblasts.     

Isolation of bioactive compounds from Helix aspersa nerve tissue and the effect of pQPPLPRYamide on heart, esophagus and central neurons of H. aspersa and rectum of Anodonta woodiana

1. Tumour necrosis factor-alpha (TNF-alpha) is implicated in the pathogenesis of many pulmonary and airway diseases. TNF-alpha stimulation may release interleukin-8 (IL-8) in airways mediated via an increase in intracellular oxidant stress. In the present study, we have assessed leukosequestration and IL-8 release in the airways in response to intratracheal administration of human recombinant TNF-alpha, and examined the modulatory role of endogenous NO by pretreatment with a NO synthase inhibitor N(omega)-nitro-L-arginine methyl ester (L-NAME). 2. TNF-alpha (10(2)-10(-4) u) was administered intratracheally in male guinea-pigs which were anaesthetized with urethane and were ventilated artificially. TNF-alpha induced a time- and dose-related increase in neutrophil numbers and a concomitant increase in human IL-8 equivalent level retrieved from bronchoalveolar lavage (BAL) with the peak effect at 10(3) u at 6 h of TNF-alpha injection (late phase). Intratracheal administration of recombinant human (rh)IL-8 (0.025, 0.25, 2.5 ng) producing a similar range of human IL-8 equivalent levels in BAL as measured in our results induced neutrophil recovery in BAL fluid to a similar extent. Administration of anti-IL-8 antibody prevented the late phase of neutrophil recruitment induced by TNF-alpha or rhIL-8. 3. Pretreatment with L-NAME significantly enhanced the TNF-alpha (10(3) u)-induced neutrophil recruitment and human IL-8 equivalents production at 6 h, but not at 1 h of TNF-alpha administration (early phase). L-Arginine reversed the responses to L-NAME. Pretreatment with 0.2% DMSO (i.v.) significantly inhibited TNF-alpha-induced neutrophil recruitment and human IL-8 equivalents release both in the early and late phase of the responses. Pretreatment with DMSO also inhibited the enhancement effect of L-NAME on the late phase of TNF-alpha-induced responses. DMSO failed to modify exogenous rhIL-8-induced neutrophil recruitment. Neither L-NAME nor DMSO alone induced any significant change in neutrophil numbers or human IL-8 equivalent level in BAL fluid. 4. Neutrophil depletion by cyclophosphamide pretreatment failed to modify TNF-alpha-induced human IL-8 equivalent release. 5. The expression of beta 2-integrin, CD11b/CD18 on neutrophils was increased only in the late but not early phase of TNF-alpha stimulation. L-NAME failed to modify these responses. 6. In conclusion, we demonstrated that NO may be an important endogenous inhibitor of TNF-alpha-induced leukocyte chemotaxis via inhibition of IL-8 production. Thus, the production of NO in airway inflammatory diseases may play a negative feedback role in self-limiting the magnitude of inflammatory responses.     

Bronchoalveolar lavage neutrophilia is associated with obliterative bronchiolitis after lung transplantation: role of IL-8

Obliterative bronchiolitis (OB) is a devastating complication in lung transplantation. We postulated that the pathogenesis of OB is mediated, in part, by neutrophils. We serially collected bronchoalveolar lavage (BAL) fluid from lung transplant recipients. Patients were divided into two groups depending on the presence or absence of OB. Samples from patients who never developed OB were further divided according to whether rejection was present. These samples were labeled healthy or rejection. Samples from patients who developed OB were divided according to whether the sample was obtained before (future OB) or at the time of diagnosis of OB (OB). The OB group, as compared with the healthy and rejection group, had significantly elevated neutrophil counts (3.9 x 10(5) +/- 1.8 x 10(5) vs 0.3 x 10(5) +/- 0.07 x 10(5) and 0.4 x 10(5) +/- 0.1 x 10(5), respectively, p < 0.01 for both) and levels of IL-8 (3131 +/- 1468 pg/ml vs 240 +/- 62 pg/ml and 172 +/- 47 pg/ml, p < 0.01 for both). Furthermore, we demonstrated immunolocalization of IL-8 associated with alpha smooth muscle actin-positive cells in the peribronchial region of OB. To confirm that the IL-8 present in BAL fluid from patients with OB was bioactive, we performed neutrophil chemotaxis experiments that showed that IL-8 accounted for a significant amount of the neutrophil chemotactic activity. We also found a trend toward higher levels of neutrophils and IL-8 in BALs from the future OB as compared with the healthy group (7.1 x 10(4) +/- 4.2 x 10(4) vs 3.4 x 10(4) +/- 0.7 x 10(4) and 500 +/- 306 pg/ml vs 240 +/- 62 pg/ml). In conclusion, we have provided the novel observation that in lung transplant recipients with OB, neutrophilia is present and highly correlated with the presence of IL-8.     

Serial prognostic capabilities of electrocardiographic indices of infarcted and hibernating myocardium in predicting short- and long-term outcome following coronary artery bypass surgery

Concentrations and ex vivo production of interleukin 1 beta (IL-1), tumour necrosis alpha (TNF), interleukin 6 (IL-6), interleukin-1 receptor antagonist (IL-1RA) and TNF soluble receptors (sTNF-receptors, P55 and P75) were measured in bronchoalveolar lavage (BAL) fluid and blood in 23 HIV-seropositive (HIV+) patients with Pneumocystis carinii pneumonia (PCP) and compared with values found in healthy HIV-seronegative (HIV-) controls and asymptomatic HIV+ subjects. Concentrations of the proinflammatory cytokine IL-1 beta were increased in BAL fluid of HIV+ patients with PCP (184 +/- 47 pg mL-1) compared with undetectable levels in healthy control subjects (P = 0.0001). In plasma of these patients higher concentrations of the anti-inflammatory cytokine IL-1RA were found during acute PCP than after recovery (2.1 +/- 0.7 vs. 0.5 +/- 0.2 ng mL-1, P = 0.01). No correlations could be found between cytokine concentrations and clinical severity of the infection. Corticosteroid treatment did not influence cytokine concentrations in BAL or blood, nor did it suppress the production in alveolar cells. In whole-blood cultures, however, lipopolysaccharide (LPS)-stimulated production was significantly suppressed for IL-1 (1.3 vs. 5.5 ng mL-1, P = 0.009) and for IL-6 (0.6 vs. 2.5 ng mL-1, P = 0.01). The overall data show that in HIV+ patients with PCP (similar to what we had found previously in HIV-patients with PCP) proinflammatory cytokines are more prominently present in BAL, whereas anti-inflammatory reaction is predominant in the circulation.     

The content of asbestos bodies in the bronchoalveolar fluid as a parameter of an increased pulmonary asbestos load

Pulmonary asbestos burdens are usually determined by quantitative pulmonary dust analysis. The aim of this study was to investigate the value of bronchoalveolar lavage (BAL) for this purpose. First, the upper limit of normal for asbestos bodies (AB) in BAL fluid was established using a reference group of 371 patients with no evidence of increased exposure to asbestos. 99% of these patients had less than 0.5 AB/ml. In order to see whether BAL fluid AB concentration reflected pulmonary tissue content, BAL fluid and lung tissue from a further 64 patients with diverse histories of asbestos exposure were investigated. There was a positive association between AB concentration in BAL fluid and lung tissue only for the overall group of 64 patients (r = 0.86; P < 0.001). Twelve of 13 patients with more than 1 AB/ml and ten patients with more than 5 AB/ml had more than 1000 AB/cm3 lung tissue, a value that is usually exceeded in asbestosis. When the upper concentration limit was set at 0.5 AB/ml for BAL fluid and 50 AB/cm3 for lung tissue, only two out of 64 patients had a false positive value (specificity 95%), but eleven patients had false negative results (sensitivity 58%). These investigations establish that concentrations of > or = 0.5 AB/ml are a reliable indicator of increased asbestos exposure and concentrations > 1 AB/ml are associated with a higher probability of having more than 1000 AB/cm3 lung tissue. However, exclusion of increased asbestos exposure is not possible on the basis of negative BAL findings, since the sensitivity of the method is too low.     

New approaches to Pseudomonas aeruginosa lower respiratory tract infections

Since 1973, the occurrence of respiratory tract infections due to P. aeruginosa has increased associated with the development of broad-spectrum penicillins. A clinical entity, diffuse panbronchiolitis (DPB) is a representative disease of chronic P. aeruginosa infections in Japan. In this paper, recent advances of research on pathogenesis and treatments of chronic P. aeruginosa lower respiratory tract infections in our department are reported. We examined sputum from patients with chronic P. aeruginosa infections under the electron microscope. Mucoid type of microcolonies were observed with fibrous matrix of exopolysaccharide. Neutrophils were found to be partially surrounding the microcolony in an attempt to defense. Debris was formed mainly by the destruction of the neutrophils. Most neutrophils were found full of phagocytized debris. These data support that instead of phagocytizing bacteria, neutrophils phagocytized debris and bacteria were not completely eradicated. This might be a factor in the pathogenesis of persistent colonization of P. aeruginosa. In the airways of patients with chronic airway diseases (CAD), neutrophils enhance the recruitment of more neutrophils through the production of neutrophil chemotactic factors such as interleukin-8 (IL-8) and LTB4, perpetuating a cycle of inflammation in the lung. We demonstrated increased levels of IL-8, a chemotactic cytokine, in bronchoalveolar lavage (BAL) fluid from patients with CAD associated with P. aeruginosa infections. We also documented a significant correlation between neutrophil numbers and IL-8 levels or IL-1 beta levels or neutrophil elastase levels in BAL fluids from patients with CAD. By immunohistochemical studies and in vitro data, three major sources of IL-8 in the airways of CAD patients were found to be alveolar macrophages, bronchial epithelial cells, and migrated neutrophils. In Japan, the clinical effectiveness of oral erythromycin (EM) for CAD, including DPB seems to be established, but its pharmacological mechanism remains unclear. In addition, we found a marked decrease of IL-8 levels in BAL fluid from two patients with CAD after treatment with EM. Therefore, we postulated that EM inhibited IL-8 production by stimulated respiratory cells. EM and Roxythromycin, suppressed IL-8 production in Pseudomonas-stimulated neutrophils in a dose-dependent manner. 1 alpha, 25-dihydroxy vitamin D3 also inhibited neutrophil-derived IL-8. Our data encourage the development of new anti-IL-8 agents against persistent P. aeruginosa lower respiratory tract infections.     

Time-dependent changes of inflammatory mediators in the lungs of humans exposed to 0.4 ppm ozone for 2 hr: a comparison of mediators found in bronchoalveolar lavage fluid 1 and 18 hr after exposure

Acute exposure of humans to ozone results in reversible respiratory function decrements and cellular and biochemical changes leading to the production of substances which can mediate inflammation and acute lung injury. While pulmonary function decrements occur almost immediately after ozone exposure, it is not known how quickly the cellular and biochemical changes indicative of inflammation occur in humans. Increased bronchoalveolar lavage (BAL) fluid levels of neutrophils (PMNs) and prostaglandins (PGE2) have been reported in humans as early as 3 hr and as late as 18 hr after exposure. The purpose of this study was to determine whether a broad range of inflammatory mediators are elevated in BAl fluid within 1 hr of exposure. We exposed eight healthy volunteers twice: once to 0.4 ppm ozone and once to filtered air. Each exposure lasted for 2 hr during which the subjects underwent intermittent heavy exercise (66 liters/min). BAL was performed 1 hr after the exposure. Ozone induced rapid increases in PMNs, total protein, LDH, alpha-1 antitrypsin, fibronectin, PGE2, thromboxane B2, C3a, tissue factor, and clotting factor VII. In addition, there was a decrease in the recovery of total cells and alveolar macrophages, and decreased ability of alveolar macrophages to phagocytize Candida albicans. A comparison of these changes with changes observed in an earlier study in which subjects underwent BAL 18 hr after an identical exposure regimen indicates that IL-6 and PGE2 levels were higher 1 hr after exposure than 18 hr after exposure, fibronectin and tissue-plasminogen activator levels were higher 18 hr after exposure, and that PMNs, protein, and C3a were present at essentially the same levels at both times. These results indicate that (i) several inflammatory mediators are already elevated 1 hr after exposure; (ii) some mediators achieve their maximal levels in BAL fluid at different times following exposure. These data suggest that the inflammatory response is complex, depending on a cascade of timed events, and that depending on the mediator of interest one must choose an appropriate sampling time.     

Effects of photochemical air pollution and allergen exposure on upper respiratory tract inflammation in asthmatics

Asthma is an inflammatory disease of the airways, and exacerbations of this disease have been associated with high levels of air pollution. The objective of this study was to examine whether ambient air pollution and/or allergen exposure induces inflammatory changes in the upper airways of asthmatics. Sixty patients with intermittent to severe persistent asthma visited the Hospital's Out Patient Clinic every 2 wk for a period of 3 mo, and on each visit a nasal lavage was obtained. Associations between nasal inflammatory parameters and seasonal allergens and/or air pollution exposures were analyzed using linear regression analysis. The study ran from July 3 to October 6, 1995, during which period ozone (8-h mean: 80 micrograms/m3) and PM10 (24-h mean: 40 micrograms/m3) were the major air pollutants; the major aeroallergen was mugwort pollen (24-h mean: 27 pollen grains/m3). Effects on both cellular and soluble markers in nasal lavage were demonstrated for both ozone and mugwort pollen, but not for PM10. Ambient ozone exposure was associated with an increase in neutrophils (112% per 100 micrograms/m3 increase in 8-h average ozone concentration), eosinophils (176%), epithelial cells (55%), IL-8 (22%), and eosinophil cationic protein (ECP) (19%). Increases in environmental mugwort pollen counts were associated with an increase in nasal eosinophils (107% per 100 pollen/m3) and ECP (23%), but not with neutrophils, epithelial cells, or lL-8. This study demonstrated that both ambient ozone and allergen exposure are associated with inflammatory responses in the upper airways of subjects with asthma, although the type of inflammation is qualitatively different.     

Biochemical and cellular composition of alveolar epithelial lining fluid in anesthetized healthy lambs

Pulmonary toxicity of inhaled materials is often evaluated by (repetitive) assessment of the composition of bronchoalveolar lavage (BAL) fluid or of epithelial lining fluid (ELF) in sheep and lambs. Knowledge of the typical constituents of these fluids obtained from healthy animals is essential for identification of pathologic changes. Few studies have dealt with normal constituents of BAL fluid or ELF in sheep and lamb. The comparability of these studies, however, is limited for reasons concerning the choice of model and BAL technique. The biochemical and cellular composition of alveolar ELF obtained by a standardized BAL procedure was examined in 15 pento-barbital anesthetized 4 months old Merino lambs unexposed to inhaled substances. ELF volume was calculated by using the urea dilution method. We found 20.3 x 10(5) leucocytes per ml ELF, 87.5% of which were alveolar macrophages. Basophils and neutrophils were practically absent while 5% of the counted cells were lymphocytes. 76% of recovered cells were viable. The ELF contained 7 mg/ml total protein; enzyme activities of LDH and AP were 1692 U/l and 145 U/l, respectively.     

Soluble L-selectin concentration in bronchoalveolar lavage fluid obtained from infants who develop chronic lung disease of prematurity

AIMS: To explore the changes in neutrophil adhesion molecule expression and release into bronchoalveolar lavage fluid (BAL) obtained from infants who developed chronic lung disease (CLD). METHODS: BAL fluid was obtained from 37 infants: 18 (median gestation 26 weeks, birthweight 835 g) who developed CLD, 12 (29 weeks, 1345 g) with respiratory distress syndrome (RDS) and seven control infants (33 weeks, 2190 g). RESULTS: Soluble L-selectin (sL-selectin) in BAL fluid from the CLD and non-CLD groups was similar immediately after birth, but in infants who subsequently developed CLD, sL-selectin remained persistently increased (at day 7: CLD 42.6 vs RDS 6.0 ng/ml, p < 0.05; CLD vs controls 1.5 ng/ml; p < 0.05). CD11b/CD18 expression on neutrophils obtained by BAL increased with time to reach a maximum at 17 days of age in infants who developed CLD. CONCLUSIONS: These results suggest that leucocyte traffic persists in infants who develop CLD and may have an important part to play in the pathogenesis of CLD.     

Alkalinizing water-soluble local anesthetic solutions by addition of cyclodextrin

OBJECTIVE: To correlate indices of airway reactivity to bronchoalveolar lavage (BAL) fluid cytologic features in horses with a recent decline in exercise tolerance. ANIMALS: 20 actively working horses from 2 to 24 years old. PROCEDURE: Bronchoalveolar lavage fluid samples were obtained and analyzed. Forced oscillatory mechanics (1-7 Hz) technique was used for measurements of total respiratory system resistance (RRS), compliance (CRS), and resonant frequency (fres). Changes in RRS (1 Hz) during histamine challenge were used to generate histamine dose-response curves, from which the provocative concentrations that evoked a 75 or 100% increase in baseline RRS (PCRRS75 and PCRRS 100, respectively) were determined. Age, sex, baseline lung mechanics, and BAL cytologic findings were correlated with PCRRS75 and PCRRS100. RESULTS: No horse of the study had clinical signs or history of obstructive pulmonary disease or increased percentage (> 7%) of neutrophils in bronchoalveolar lavage fluid samples. Mean (+/- SEM) RRS, CRS, and fres were 0.67 +/- 0.06 cm of H2O/L/s, 0.52 +/- 0.04 L/cm H2O, and 2.46 +/- 0.02 Hz, respectively. There was no correlation between age or sex, and RRS, CRS, fres, PCRRS75, or PCRRS100. There was a significant correlation (rs = -0.78, P < 0.001) between percentage of BAL fluid mast cells and PCRRS75 or PCRRS100, but correlation with other cell types and indices of airway reactivity were not observed. CONCLUSION: The strong association between mast cell percentage in BAL fluid and airway reactivity in this group suggests that mast cell products may contribute to bronchospasm, airway wall thickening, and/or loss of elastic recoil, which underlie airway hyperreactivity. Alternatively, mast cells may contribute to nonspecific airway reactivity in horses through unknown mechanisms.     

Neutrophil recruitment by human IL-17 via C-X-C chemokine release in the airways

IL-17 is a recently discovered cytokine that can be released from activated human CD4+ T lymphocytes. This study assessed the proinflammatory effects of human (h) IL-17 in the airways. In vitro, hIL-17 increased the release of IL-8 in human bronchial epithelial and venous endothelial cells, in a time- and concentration-dependent fashion. This effect of hIL-17 was inhibited by cotreatment with an anti-hIL-17 Ab and was potentiated by hTNF-alpha. In addition, hIL-17 increased the expression of hIL-8 mRNA in bronchial epithelial cells. Conditioned medium from hIL-17-treated bronchial epithelial cells increased human neutrophil migration in vitro. This effect was blocked by an anti-hIL-8 Ab. In vivo, intratracheal instillation of hIL-17 selectively recruited neutrophils into rat airways. This recruitment of neutrophils into the airways was inhibited by an anti-hIL-17 Ab and accompanied by increased levels of rat macrophage inflammatory protein-2 (rMIP-2) in bronchoalveolar lavage (BAL) fluid. The BAL neutrophilia was also blocked by an anti-rMIP-2 Ab. The effect of hIL-17 on the release of hIL-8 and rMIP-2 was also inhibited by glucocorticoids, in vitro and in vivo, respectively. These data demonstrate that hIL-17 can specifically and selectively recruit neutrophils into the airways via the release of C-X-C chemokines from bronchial epithelial cells and suggest a novel mechanism linking the activation of T-lymphocytes to recruitment of neutrophils into the airways.