Enhanced reactive oxygen species metabolism of air space cells in hypersensitivity pneumonitis

Reactive oxygen species (ROS) are produced by phagocytic cells as part of host defense mechanisms, but these same products released by air space cells have been shown to contribute to pulmonary inflammation in interstitial lung diseases and likely represent a general mechanism of lung injury. However, the possible contribution of these compounds to lung inflammation in hypersensitivity pneumonitis (HP) has yet to be reported. We performed 11 bronchoalveolar lavage (BAL) studies in six patients with HP and compared the results with results from studies in 21 healthy normal volunteers. In patients with HP, spontaneous and stimulated measures of ROS metabolism by air space cells were significantly higher than those seen in normal volunteers. When alveolar macrophages were purified by depleting neutrophils and eosinophils on density gradients of Percoll (specific gravity 1.075 gm/ml), ROS metabolism remained elevated when compared with that in cells obtained from healthy controls, confirming that alveolar macrophage ROS metabolism is enhanced in patients with HP. Further, we found significant elevations in BAL total protein, lymphocytes, eosinophils, and neutrophils in patients with HP when they were compared with normal volunteers, with an increased proportion of BAL T lymphocytes expressing CD8 and natural killer surface antigens, consistent with previous work. Lavage samples from patients with HP with clinically active disease had higher proportions of BAL eosinophils and concentrations of total protein, lower forced expiratory volume in 1 second, lower forced vital capacity, and lower arterial oxygen tensions, and higher indices of ROS metabolism than samples from patients with HP with inactive disease. HP is associated with evidence of air space inflammation, to which alveolar macrophage-derived ROS may contribute.

T cells, macrophages and platelets in asthma

The role of T cells, macrophages and platelets in asthma is discussed. Peripheric T cell populations are normal as well in atopic as in non atopic. Macrophages can release histamine releasing factors and PAF in presence of allergens. Platelets stimulated by contact with allergens or PAF decreased the aggregation pattern induced by common inducers. These data show that different cells can play a role in the inflammatory process in asthma.

Expression of 1,25(OH)2D3 receptors on alveolar lymphocytes from patients with pulmonary granulomatous diseases

1,25(OH)2D3 is known to be produced at sites of granulomatous reactions. In order to characterize the cell types that are targets for this immunoregulatory hormone, we have evaluated the expression of 1,25(OH)2D3 receptors on peripheral blood T-lymphocytes and those recovered from the lung by bronchoalveolar lavage from patients with pulmonary granulomatous diseases (tuberculosis and sarcoidosis) and from normal control subjects using combined autoradiographic and immunohistochemical techniques. Lavage T-lymphocytes from patients with tuberculosis or with sarcoidosis, but not those from normal control subjects, expressed 1,25(OH)2D3 receptors as demonstrated by binding of [3H]1,25(OH)2D3, which was inhibited by the presence of excess unlabeled 1,25(OH)2D3, but not by the presence of unlabeled 25(OH)D3 (receptor-positive lymphocytes: sarcoidosis, 20 +/- 12%; tuberculosis, 31 +/- 17%). In contrast, blood lymphocytes from patients with granulomatous diseases did not express detectable 1,25(OH)2D3 receptors. The percentage of lavage T-lymphocytes expressing 1,25(OH)2D3 receptors was significantly greater for patients with tuberculosis presenting with isolated hilar adenopathy than for patients with pulmonary infiltrates and/or cavities. 1,25(OH)2D3 receptors were expressed to a greater extent on CD8+ T-lymphocytes than on CD4+ T-lymphocytes in sarcoidosis, whereas a greater proportion of CD4+ than of CD8+ T-lymphocytes from patients with tuberculosis were receptor-positive. These findings support the conclusion that the interaction of 1,25(OH)2D3 with its receptor on T-lymphocytes may play an important role in the regulation of granulomatous reactions, but because these receptors are expressed on different lymphocyte populations, the net effect of this potent immunoregulatory molecule is likely different in sarcoidosis and tuberculosis.

[Three cases of minocycline-induced pneumonitis]

All three patients complained of cough, fever and dyspnea. Their chest X-ray films revealed interstitial changes such as Kerley B lines. The results of lymphocyte stimulation tests were all negative for Minocycline (MINO), whereas the provocation tests were all positive in three cases. The onsets of symptoms appeared 7, 12 and 9 hours after administration of MINO respectively, which suggested type III allergy in terms of the latency period. In cases No. 1 and No. 3, lung tissue specimens obtained by transbronchial biopsy showed findings of mild acute eosinophilic pneumonia. The bronchoalveolar lavage fluid of case No. 3 showed eosinophilia. On diagnosing MINO-induced pneumonitis, the lymphocyte stimulation test is not always beneficial, whereas the provocation test is supposed to be a safe and sure method.

Therapeutic intervention in a rat model of adult respiratory distress syndrome: II. Lipoxygenase pathway inhibition

The present study was designed to investigate the role of 5-lipoxygenase (5LO) metabolites in an endotoxin (LPS)-induced model of the adult respiratory distress syndrome (ARDS) in the rat. The therapeutic value of two 5LO inhibitors and a specific LTB4 and a LTD4 receptor antagonist were examined. Rats were treated 1 hr prior to administration of aerosolized LPS. Rats were either unexposed (n = 11), or pretreated with vehicle sham (n = 63), 50 mg/kg phenidone t.i.d. (n = 7, n = 10 for assessment of mortality), 30 mg/kg SK&F 103842 b.i.d. (n = 6), 50 mg/kg SK&F 106203 t.i.d. (n = 11), or 5 mg/kg SK&F 107324 b.i.d. (n = 6) 1 hr prior to the administration of aerosolized endotoxin (LPS, 7 mg/kg) or phosphate-buffered saline (PBS, n = 22). Twenty-four hours later, blood samples were collected for hematologic evaluation and after wet lung weight was determined, broncho-alveolar lavage (BAL) was performed to measure cells counts and total protein (TP). 5LO inhibition and LTD4 receptor antagonism reduced LPS-induced mortality to zero compared to 35% in rats pretreated with vehicle sham. Pretreatment with the LTD4 receptor antagonist attenuated the LPS-induced increased in wet/dry lung weight (W/D) whereas 5LO inhibition reduced TP increases. Both 5LO inhibition and LTD4 receptor antagonism attenuated the LPS-induced BAL erythrocyte increase. The LPS-induced thrombocytopenia was attenuated by phenidone, the 5LO receptor antagonist. We conclude that the increased microvascular permeability was associated with the formation of 5LO products since 5LO inhibition lessened the severity of the LPS-induced increase in W/D and TP.(ABSTRACT TRUNCATED AT 250 WORDS)

Correlation of lower respiratory tract inflammation with changes in lung function and chest roentgenograms in patients with untreated tropical pulmonary eosinophilia

Forty-one patients with untreated tropical pulmonary eosinophilia (TPE) were studied to determine whether there was any relationship between lower respiratory tract inflammation and either changes in lung function or abnormalities in chest roentgenograms. Total number of inflammatory cells in bronchoalveolar lavage (BAL) fluid, consisting of alveolar macrophages, lymphocytes, eosinophils and neutrophils had significant negative correlations with transfer factor (TLCO) (r = 0.519, p less than 0.001), transfer coefficient (KCO) (r = 0.312, p less than 0.05) and total lung capacity (TLC) (r = 0.352, p less than 0.05). The absolute count of eosinophils in BAL fluid had a significant negative correlation with TLCO (r = 0.430, p less than 0.01) and KCO (r = 0.300, p = 0.05), but not with forced vital capacity (FVC), forced expiratory volume in 1 second (FEV1) or TLC. However, the absolute count of alveolar macrophages had a significant negative correlation with FVC (r = 0.343, p less than 0.05), FEV1 (r = 0.341, p less than 0.05) and TLC (r = 0.305, p less than 0.05), but not with TLCO or KCO. The total number of lymphocytes had a negative correlation with TLC (r = 0.315, p less than 0.05). There was no correlation between the types of cells recovered in BAL fluid and changes in chest radiographs as assessed by the ILO classification for occupational lung diseases. These data suggest that there may be a dissociation of pulmonary pathophysiological changes produced by different inflammatory cells in the lower respiratory tract. Macrophages and lymphocytes may produce more harm to the lung, as evidenced by significant negative correlations of these cells with lung volumes.

Therapeutic intervention in a rat model of adult respiratory distress syndrome: III. Cyclooxygenase pathway inhibition

Current strategies for the treatment of ARDS have been unsuccessful in reducing mortality. In the present study, we have evaluated the role of cyclooxygenase (CO) products in a rat model of ARDS by testing naproxen, indomethacin, ibuprofen, and a thromboxane A2 (TXA2) receptor antagonist (SK&F 96148). Rats were treated 1 hr prior to endotoxin (LPS) exposure and 24 hr later, survival, body weight changes, wet/dry lung weight (W/D), total protein content (TP) of the bronchoalveolar lavage (BAL) fluid, and total erythrocyte and differential leukocyte counts of the BAL fluid were measured. In addition, the following hematologic measurements were taken: hemoglobin (Hb), hematocrit (Hct), circulating erythrocyte, differential leukocyte, and platelet counts. Treatment with the TXA2 receptor antagonist reduced mortality to zero after 24 hr after LPS administration. Other compounds had no significant effect on LPS-induced mortality. Pretreatment with CO inhibitors or the TXA2 receptor antagonist attenuated the LPS-induced increase in TP and W/D. Although all compounds tended to reduce the LPS-induced increase in BAL erythrocytes, only the TXA2 receptor antagonist did so significantly. The LPS-induced increase in BAL neutrophil counts was significantly reduced by 30 mg/kg ibuprofen, but not by the other compounds. In fact, the TXA2 receptor antagonist actually exacerbated BAL neutrophil counts, but diminished the peripheral neutrophilia and lymphopenia induced by LPS. None of the CO inhibitors tested significantly affected LPS-induced hematologic responses. We conclude that by virtue of its protection against LPS-induced mortality, the TXA2 receptor antagonist was the most effective compound in this model. However, it did cause certain negative side effects such as increased pulmonary inflammation.(ABSTRACT TRUNCATED AT 250 WORDS)

[Histopathological diagnosis of diffuse interstitial lung diseases]

The histopathological diagnosis of chronic diffuse infiltrative lung diseases rests on elements provided by bronchoalveolar lavage, fibroscopic transbronchial biopsy and, less frequently, surgical lung biopsy. The microscopic study sometimes leads to an accurate diagnosis that fits with the clinical context, but in other cases the morphological evaluation is purely lesional and must be discussed in the light of clinical, radiological and functional data.

Bronchoalveolar lavage cell data in amiodarone-associated pneumonitis. Evaluation in 22 patients

To assess the value of bronchoalveolar lavage (BAL) for diagnosis, understanding, and treatment of amiodarone-associated pneumonitis, we examined the results of BAL total and differential cell counts and phenotyping of lymphocytes in 22 patients with this lung disorder and in 33 normal subjects. Overall, the total cell count was found to be almost the same as that seen in control subjects; the macrophage population was significantly reduced, and the lymphocyte, neutrophil, and eosinophil populations were increased in absolute number and percentage. When results were analyzed individually, BAL data appeared to be distributed according to two patterns. In the first pattern, there was no abnormal lymphocytosis. In the second pattern a lymphocyte alveolitis was found in percentage and in absolute number. This lymphocyte alveolitis was present either alone or associated with neutrophil alveolitis or with eosinophil alveolitis. In the first pattern, despite the normal level of the lymphocyte population, the percentage of CD4 T-lymphocytes and the CD4:CD8 T-lymphocyte ratio were significantly lowered. In the second pattern the CD8 T-lymphocyte count was increased in absolute number and percentage, with a low CD4:CD8 ratio. In six patients relavaged two to four months after amiodarone withdrawal, there was a significant fall in alveolar lymphocytosis, but the progressive increase in the neutrophil population over time seemed to be associated with the seriousness and progression of the disease. Finally, these findings closely resembled those obtained in patients with hypersensitivity pneumonitis due to inhalation of organic dust and suggest that an underlying immunologic cell-mediated mechanism may play a role in this iatrogenic pulmonary disease.

Effect of corticosteroid therapy on the acute injury and recovery stage of oleic acid induced lung injury in the rat

In the rat model of lung injury induced by oleic acid (OA), we studied the effect of corticosteroid therapy on pulmonary inflammation and compliance at acute (1 day post OA) and recovery (3 and 7 days post OA) stages. Methylprednisolone (MP) and dexamethasone (DM) were examined for therapeutic benefit in this model. Histologic examination, lung compliance, and analysis of bronchoalveolar lavage (BAL) fluid were used to assess lung injury. Our results demonstrated that, at 1 day post OA, both steroids effectively reduced pulmonary inflammation and restored lung compliance when compared to animals that received only OA. In comparison to DM, MP was more effective in inhibiting the pulmonary inflammation induced by OA, but was less effective in restoring lung compliance. However, at 3 and 7 days post OA, cell and/or protein levels in BAL fluid from both MP- and DM-treated OA animals were significantly higher than levels observed in animals that received only OA. Lung compliance returned to normal by 3 days in animals that received only OA. This effect, however, was blocked in OA animals that were treated with either steroid, MP, or DM. Our data suggest that steroid therapy can be beneficial in the acute stage of OA-induced lung injury, but appears to be detrimental during the early recovery stage, perhaps by inhibiting the repair process.

Epithelial injury, inflammation, and repair in the hamster lung following intratracheal instillation of enzyme-generated oxidants

Oxidant-induced inflammatory and morphologic changes evoked by intratracheally instilled glucose, active glucose oxidase, and lactoperoxidase in hamsters are described. Similar solutions containing heat-denatured (DE) glucose oxidase served as a control treatment. During the 7-week post-treatment period, animals were sacrificed and lavaged, and their lungs were preserved for later study. Although a neutrophil-rich alveolitis was observed initially in both groups, the leukocytic influx and mild morphologic changes in DE-treated animals resolved within 7 days. In contrast, glucose oxidase mixtures caused necrotic alveolar epithelium, fibrin-like exudate, and significantly higher neutrophil and protein levels in bronchoalveolar lavage fluid (BALF) after 1 day. At 4 days, type II cell hyperplasia was extensive and BALF levels of all inflammatory cell types were significantly greater than BALF counts in DE animals. By 7 days, BALF macrophage and lymphocyte levels remained significantly elevated, and epithelial hyperplasia coincided with marked increases in lung hydroxyproline and interstitial cells. BALF parameters suggested that inflammation induced by glucose oxidase resolved within 15 days, yet total hydroxyproline levels remained elevated at 15 days and epithelial lesions were still detectable at 29 days. Oxidant-induced inflammation and epithelial injury were transient and preceded moderate collagen deposition.

Diagnosis of cytomegalovirus pneumonitis on bronchoalveolar lavage fluid: comparison of cytology, immunofluorescence, and in situ hybridization with viral isolation

Forty-three bronchoalveolar lavage (BAL) specimens from 40 immunocompromised patients were studied for the presence of cytomegalovirus (CMV) by rapid diagnostic methods. DNA in situ hybridization, cytology, and immunofluorescence were compared to conventional cell culture. Eleven (25%) of the 43 BAL samples grew CMV in culture. In situ hybridization detected 6 of these 11 for sensitivity, specificity, and predictive values of positive and negative of 55%, 94%, 75%, and 86%, respectively. Cytology had a sensitivity of 73% and specificity of 100%. Six Papanicolaou-stained cytospins were screened cytologically versus one hybridization cytospin, and the higher sensitivity of cytology may reflect this extensive sampling. The immunofluorescent method had a sensitivity equal to that of cytology (73%): however, the specificity (72%) was significantly less than that of either the probe or cytology. These data suggest that although in situ hybridization can be a rapid, useful method for detecting CMV in BAL specimens, cytology appears to be a more sensitive method.

Endobronchial biopsy positive sarcoidosis: relation to bronchoalveolar lavage and course of disease

Sixty-two patients with newly diagnosed sarcoidosis were examined with fibreoptic bronchoscopy, endobronchial biopsies and bronchoalveolar lavage (BAL) were analysed. Epithelioid granulomatosis in endobronchial biopsies were found in 28 (45%) of the patients (BPOS). The patients in this BPOS group showed higher inflammatory activity in BAL fluid compared to those with negative biopsies (BNEG), with significant increases in lymphocyte and mast cell counts, and concentrations of procollagen III peptide and albumin. The patients were followed over a period of 2 years. The BPOS group tended to have a worse clinical course with more patients having a progressive disease and more patients requiring treatment with systemic steroids. We conclude that the findings of epithelioid granulomatosis in endobronchial biopsies may reflect a more intense and widespread inflammation in the lung.

[CD8+T-cell lymphocytic alveolitis in sarcoidosis. 4 cases]

We report 4 cases of histologically proven sarcoidosis with lymphocytic alveolitis. The T CD4+/T CD8+ ratio was below 1 in the bronchoalveolar lavage fluid. Since there was no clinical and paraclinical evidence of extrinsic allergic alveolitis or HIV infection, and since 3 of the patients were nonsmokers and the 4th one smoked moderately, we considered that the T CD8+ lymphocytic alveolitis was related to the sarcoidosis. In 3 patients the presence of mediastinal adenopathy suggested that sarcoidosis was of recent onset. The fact that T CD4+/T CD8+ ratio was normal in blood indicated that T CD8+ lymphocytes were predominant only in the lung. Thus, the finding of T CD8+ lymphocytic alveolitis should not exclude a diagnosis of sarcoidosis.

Phenotypic expression of bronchoalveolar lavage cells in lung rejection and infection

The differentiation of episodes of lung allograft rejection from infection continues to be a problem. Bronchoalveolar lavage (BAL) has recently gained some success in the diagnosis and management of interstitial lung disease. To assess the usefulness of BAL in differentiating between lung allograft rejection and infection, we examined the differences in cellular subsets of BAL and peripheral blood (PBL) samples in a controlled canine model of rejection or pneumonia. Single-lung allotransplants were allowed to undergo rejection by withdrawing immunosuppressive agents (n = 6). In another group of dogs (n = 5), pneumonia was induced by transbronchial injection of Pseudomonas aeruginosa and melted agar followed by bronchial fulguration. Cells obtained from bronchoscopic BAL and PBL samples were labeled with functionally characterized cross-reactive murine monoclonal antibodies. Transthoracic needle biopsies and transbronchial biopsies were done to assess their adequacy in examining the rejecting or infected lungs and were compared with open lung biopsies. We found the following: (1) the percentage of DT2-labeled cells was significantly higher (p less than 0.05) in BAL samples from rejecting lungs compared with infected lungs; (2) the PBL/BAL ratio of DT2-labeled cell percentages was significantly higher in pneumonia (1.7 +/- 0.3) than rejection (0.5 +/- 0.2) (p less than 0.004); (3) the percentage of E11-labeled cells in PBL samples was significantly higher (p less than 0.02) in rejection than in infection; and (4) the ratio of WIG4 to DT2 cellular subset percentages in BAL samples from rejection (26.8 +/- 9.9) was significantly lower than from infection (61.0 +/- 22.9) (p less than 0.03). Transthoracic and transbronchial biopsies did not always yield representative specimens.(ABSTRACT TRUNCATED AT 250 WORDS)

Pathology of pulmonary parasitic migration: morphological and bronchoalveolar cellular responses following Nippostrongylus brasiliensis infection in rats

Nippostrongylus brasiliensis has an obligatory migratory phase through the lungs during its development in rats. This migration is associated with marked tissue damage and pronounced cellular reaction. Given that cells from the lower respiratory tract, especially alveolar macrophages, can adhere to and kill larvae of N. brasiliensis in vitro, we studied the time course of morphological changes associated with parasitic migration. Compared to a primary infection, a secondary infection resulted in significant changes in the pulmonary tissue characterized by an early acute inflammation leading to granulomatous reaction in the parenchyma and a leucocytosis in the bronchoalveolar lavage fluids with an anamnestic increase in absolute numbers of neutrophils, alveolar macrophages, eosinophils, and lymphocytes. Scanning electron microscopy showed that inflammatory cells, especially alveolar macrophages, granulocytes, lymphocytes, erythrocytes, and platelets, adhered to the larvae following secondary infection and this adhesion was associated with disruption of cuticular surface in some larvae. Secondary infection also resulted in retention of larvae in granulomatous lesions in the lungs even up to 21 days postinfection. There was mast cell and type II pneumocyte hyperplasia and these cells appeared to be activated. Thus, the histopathological changes in lungs correlated with the bronchoalveolar cellular responses and further document the inflammatory and immunological reactions during the migration of N. brasiliensis larvae.

Frequent identification of HIV-1 DNA in bronchoalveolar lavage cells obtained from individuals with the acquired immunodeficiency syndrome

Tissue macrophages are recognized as a cellular target for infection with the human immunodeficiency virus type 1 (HIV-1). To characterize the nature of this cell-retrovirus interaction within the lower respiratory tract we analyzed fluid and cells obtained by bronchoalveolar lavage (BAL) of eight individuals with acquired immunodeficiency syndrome (AIDS) who were undergoing diagnostic fiberoptic bronchoscopy. Of these eight individuals, seven had active infection with Pneumocystis carinii; one had suspected cytomegalovirus pneumonitis. At the time of study two were receiving the antiretroviral drug zidovudine (azidothymidine [AZT]). HIV-1 could not be isolated from any of the eight samples of BAL fluid concentrated by ultracentrifugation through 20% sucrose. HIV-1 antigen (p24) was detected in one of eight samples of concentrated BAL fluid but could not be found in eight samples of media conditioned by overnight incubation with adherent BAL cells. Despite the infrequent detection of HIV-1 antigen it was possible to identify HIV-1 genomic sequences by the use of a DNA amplification technique, the polymerase chain reaction, in all eight BAL cell preparations. In BAL cells adherent for up to 5 days in culture this method detected retroviral DNA that hybridized to a complementary pair of primers located in the env and gag gene regions of HIV-1. These studies demonstrate the uniform presence of HIV-1 harboring cells within the airways of the lung in individuals with AIDS and active respiratory infection and may have implications for local organ defense.(ABSTRACT TRUNCATED AT 250 WORDS)

A bradykinin antagonist modifies allergen-induced mediator release and late bronchial responses in sheep

We assessed the role of bradykinin (BK) in allergen-induced early and late bronchial responses, airway inflammation, mediator release, and antigen-induced airway hyperresponsiveness in allergic sheep by studying the effects of the BK B2 receptor antagonist, NPC-567 (D-Arg-[Hyp3, D-Phe7]-BK), on these parameters. Antigen challenge was performed on two occasions greater than 3 wk apart, once with placebo (control) and once after high-dose (10 mg/ml) and low-dose (5 mg/ml) treatments with aerosol NPC-567. In the control trials (n = 14) antigen challenge resulted in an early and late increase in specific lung resistance (SRL). The early response was associated with increases (p less than 0.05) in prostaglandin (PG) D2, immunoreactive kinin, tosyl-L-arginine methyl ester (TAME)-esterase, and PGE2 in bronchoalveolar lavage (BAL) fluid. The late response was associated with increases (p less than 0.05) in leukotrienes (LT) B4 and C4, thromboxane (TX) B2, 6-keto-PGF10, and PGE2. There was a significant influx of neutrophils in the BAL fluid during the late response, and airway hyperresponsiveness to carbachol aerosol was apparent 4 h after challenge. In six sheep the high-dose NPC-567 treatment (given before, during, and 4 h after antigen challenge) did not attenuate the early bronchoconstrictor response or the early release of mediators but caused a significant reduction in the late response (p less than 0.05). This protective effect was accompanied by reductions (p less than 0.05) in both the concentrations of all the mediators associated with the late response and the severity of the BAL neutrophilia. High-dose NPC-567 did not attenuate the airway hyperresponsiveness or the cellular inflammatory response seen 24 h after challenge. In eight sheep treated with the low dose of NPC-567 (given before, during, and 4, 8, and 24 h after challenge) the early response was not blocked but the late response was again inhibited, as were the mediators associated with the late response. At the low dose the drug did not prevent the airway inflammation at 8 or 24 h. The additional treatments did, however, prevent the 24 h hyperresponsiveness. These data suggest that kinin generation during antigen-induced airway anaphylaxis may be important for controlling the release of arachidonic acid metabolites from airway inflammatory cells that contribute to the development of the late response in the allergic sheep model.

Cellular and biochemical characteristics of bronchoalveolar lavage fluid in symptomatic nonallergic asthma

We have undertaken cellular and biochemical examination of bronchoalveolar lavage fluid from nonallergic patients with asthma to determine the nature and degree of inflammatory process in symptomatic asthma. Six patients with asthma (mean methacholine provocative concentration causing a 20% fall in FEV1 was 0.26 mg/ml) and six control subjects underwent fiberoptic bronchoscopy with bronchoalveolar wash. The patients with asthma shed a higher number of epithelial cells into lavage fluid than normal control subjects (p less than 0.05). Their lavage fluid also contained increased numbers of neutrophils (p less than 0.025), eosinophils (p less than 0.025), and basophilic cells (p less than 0.025), and increased proportion of activated T cells (p less than 0.05). The basophilic cells were mast cells, as indicated by positive labeling with the monoclonal antibody MCG35. Biochemical analysis of lavage fluid demonstrated exudation of protein molecules in airways of patients with asthma with increased contents of albumin (p less than 0.05) and fibronectin (p less than 0.05). In the lavage fluid of patients with asthma, there were also increased amounts of interleukin-1-beta (IL-1-beta) (p less than 0.025), interleukin-6 (IL-6) (p less than 0.025), and granulocyte-macrophage, colony-stimulating factor (GM-CSF) (p less than 0.05), as compared with lavage fluid of normal control subjects. Immunocytochemical evaluation of lavage cells demonstrated that IL-1-beta, IL-6, and GM-CSF were mostly produced by nonciliated epithelial cells and/or monocytes. IL-1, IL-6, and GM-CSF can prime granulocytes to respond to other stimuli and can promote T cell activation.(ABSTRACT TRUNCATED AT 250 WORDS)

Protected bronchoalveolar lavage. A new bronchoscopic technique to retrieve uncontaminated distal airway secretions

We tested the effectiveness of protected bronchoalveolar lavage (PBAL), performed through a protected transbronchoscopic balloon-tipped (PBT) catheter, in collecting distal airway secretions with a minimal degree of contamination. The PBAL had less than or equal to 1% squamous epithelial cells in 91% of specimens and an absence of bacterial growth in 59% of patients without pneumonia. Using a threshold of 10(4) cfu/ml we had one false positive result in 33 patient without pneumonia and one false negative in 13 patients with pneumonia. Quantitative bacterial cultures of the PBAL specimens had a diagnostic sensitivity of 97% and a specificity of 92%, with a positive predictive value of 97% and a negative predictive value of 92%. The diagnostic efficiency was 96%. The presence of intracellular organisms in much greater than or equal to 2% of the recovered alveolar cells (Giemsa stain) was seen in all but two patients with pneumonia (on corticosteroids) and in none of the patients without pneumonia. Gram stains of the PBAL specimens were positive in all but one patient with pneumonia and negative in all but one patient without infection (patient with endobronchial narrowing secondary to neoplasm with false positive cultures). Either the Giemsa or the Gram stain was positive in all patients with pneumonia, allowing early and accurate diagnosis of lower respiratory tract infection before the results of cultures were available. The time off antibiotic therapy before bronchoscopy did not affect the result of PBAL cultures, contrary to what we observed for the protected brush specimen.

Eosinophil activation in systemic sclerosis

Circulating levels of eosinophil cationic protein (ECP) were increased 4-fold in patients with systemic sclerosis (SSc) compared with those in healthy control subjects. There was no correlation between the ECP concentrations and laboratory indices of inflammatory activity or visceral involvement. Mean ECP levels were higher in patients with a history of occupational exposure to silica, even though patients who had no such history also had ECP levels higher than normal. The patients had increased bronchoalveolar levels of ECP, which correlated with impaired lung functioning. Skin infiltration with activated eosinophils and extracellular deposits of ECP were present in skin biopsy samples from the SSc patients. We conclude that eosinophil activation is part of the inflammatory process in SSc.

Ozone stress initiates acute perturbations of secreted surfactant membranes

To identify the early changes of surfactant secretion in response to acute oxidant stress, the authors evaluated morphometrically centriacinar type II cells and lavage fluid surfactant forms obtained immediately after exposure of adult rats to 3 ppm ozone for 1, 2, 4, or 8 hours. In this model, the rat lung develops progressive alveolar edema with significant elevation of lavage fluid proteins at 2 to 8 hours of exposure. Ultrastructural changes in type II cells at 1 and 2 hours included enhanced lamellar body (LB) fusion with significant increase in the compound and vacuolated LB compartments. Parallel changes of lavage fluid surfactant membranes included a sustained, twofold increase in the proportion of loosely coiled multilamellar structures at 1 to 8 hours, with reciprocal decrease in the proportion of tubular myelin from control value of 56% to 34%. The proportion of densely coiled LB-like forms in lavage fluid increased significantly at 4 and 8 hours, whereas the proportions of unilamellar structures remained unchanged. The results indicate that ozone-induced alveolar injury initiates time-dependent defects in the organization of stored and secreted surfactant membranes. The acute ozone stress inhibits unfolding of secreted lamellar body membranes as well as their organization into tubular myelin, thereby perturbing the proportions of extracellular surfactant membranes that are available for adsorption onto the surface film.

Bronchoalveolar lavage fluid cytologic findings in horses with pneumonia or pleuropneumonia

Bronchoalveolar lavage was performed in 22 horses with pneumonia or pleuropneumonia. All horses had clinical evidence of pneumonia or pleuropneumonia on the basis of physical, radiographic, ultrasonographic, tracheobronchial aspirate or post-mortem findings. Results of lavage fluid analysis were normal in 9 horses, equivocal in 3 horses, and abnormal in 10 horses. Abnormal lavage fluid had increased total cell count, increased relative and absolute neutrophil counts, degenerative neutrophils, and decreased relative and absolute macrophage and lymphocyte counts.