Efficacy of two breath condensers

BACKGROUND

Examination of Exhaled Breath Condensate has been suggested to give information about inflammatory airway diseases.

OBJECTIVES

The aim was to compare efficacy and variability in gain of two commercially available exhaled breath condensers, ECoScreen and RTube in an in vitro set up.

METHODS

Test fluids containing myeloperoxidase (MPO) or human neutrophil lipocalin (HNL) in addition to saline and bovine serum albumin were nebulized and aerosols were transferred by a servo ventilator to either of the two condensers. Analyses of MPO, HNL, or chlorine were done by means of ELISA, RIA, or a modified adsorbed organic halogen technique (AOX), respectively.

RESULTS

Recoveries of HNL were higher when using ECoScreen than RTube (P<0.05). In contrast, there were no significant differences between the two condensers in recoveries of MPO or chlorine. The spread of data was wide regarding all tested compounds.

CONCLUSION

Variability in gain was large and ECoScreen was more efficacious then RTube in condensing the tested solutes of HNL, but not those of MPO or chlorine.

Mesangial IgA glomerulonephritis in adults. Clinical and histopathological observations

This report evaluates 29 patients with IgA glomerulonephritis. Patients with the least intensity of immunofluorescent staining for IgA had the highest glomerular filtration rate. The pattern or intensity of the staining gave little or no indication of the severity of the morphological changes or of the short-term prognosis. Histological changes with increased amounts of adherences were found in a significantly higher proportion of kidneys with decreased function. Older patients had a longer history and a higher incidence of low renal function, and they showed more glomerular adherences and global fibrosis than younger patients.

Indices of inflammatory cell activity and pulmonary function in different stages of sarcoidosis

The present study was carried out to compare radiological and physiological changes in sarcoidosis with biochemical markers for inflammatory cell populations. Of 53 patients with sarcoidosis, 28 had respiratory symptoms and 30 past or present bilateral hilar adenopathy without symptoms. A clinical score based on lung function tests and radiological findings correlated well with elevations of lysozyme and beta2-microglobulin in serum, indicating increased inflammatory cell activity in patients with more severe lung affection. A covariation between beta2-microglobulin and lysozyme was found, suggesting concomitant activation of macrophages and lymphocytes in sarcoidosis. Serum levels of lactoferrin were elevated in patients with a disease of short duration but did not correlate with the severity of the lung affection. The closing volume also seems to be abnormal in the early course of the disease, while elevated lysozyme and beta2-microglobulin levels rather seem to reflect the extent of the pulmonary affection.

Quantitative assessment and repeatability of chlorine in exhaled breath condensate

BACKGROUND

Airway condition is presumably reflected in epithelial lining fluid (ELF). Exhaled breath condensate (EBC) has been used as a surrogate marker of the composition of ELF.

OBJECTIVES

This study aimed at assessing the technical repeatability of chlorine measurements in EBC and comparing two separate condensators (Ecoscreen and R Tube regarding recovery and repeatability. Furthermore, the association between condensate recoveries and variations in the airway status were scrutinized.

METHODS

EBC was collected using two condensators from 10 healthy volunteers. In addition, 13 asthmatic patients produced EBC with or without an added resistance of 5 cm H2O (Res5), applied to the outflow tract of Ecoscreen. All tests were done in random order. Chlorine levels (analyzed by a coulometric technique) in EBC served as a tool for investigation.

RESULTS

Chlorine was measurable in all samples. The coefficient of repeatability of chlorine measurements was <10%. Chlorine levels were higher in EBC obtained from R Tube (p < 0.001), and differences in recoveries and variability in chlorine levels were presumably related to technical differences in the condensators and not to the repeatability of chlorine measurements per se. Air-flow-dependent chlorine levels were obtained from healthy volunteers. Application of Res5, recruiting additional alveoli, resulted in increased recovery of the EBC volume, but not of chlorine, from those that had the most pronounced airway obstruction (p = 0.05).

CONCLUSION

We conclude that by employing a sensitive analysis technique, chlorine is repeatedly measurable in EBC. We suggest that the bulk of chlorine in EBC originates from large airways and not from the alveolar area. Both condensators were comparable regarding repeatability but differed regarding chlorine recovery.

Eosinophil cationic protein (ECP) in saliva: a new marker of disease activity in bronchial asthma

Eosinophil cells play a crucial role in the pathogenesis of asthma, and concentration of eosinophil cationic protein (ECP) in serum has been used to monitor activity of the disease. Our aim was to determine the feasibility and usefulness of measuring ECP in saliva and to use it as a marker of the disease. Thirty-eight patients with asthma and 16 healthy volunteers were included in this study. Repeatability of measurements of ECP in saliva was acceptable [intra-class correlation coefficients (Ri) = 0.74 and coefficients of repeatability (CR) = 0.37 in five healthy subjects]. Levels of ECP in saliva were higher in asthmatics than in volunteers (P < 0.01). There was a significant inverse association between a surrogate variable reflecting disease activity (i.e. change over a few weeks in dose of inhaled corticosteroid required by a change in clinical status of asthma) and a change over the same time period in salivary ECP in 19 patients with stable asthma (r = -0.64, P = 0.02). Our findings indicate that levels of salivary ECP are elevated in patients with asthma and associated with presumed activity of disease as recorded by alteration of taken dose of inhaled corticosteroid.

Human neutrophil lipocalin (HNL) and myeloperoxidase (MPO). Studies of lung lavage fluid and lung tissue

Myeloperoxidase (MPO) and human neutrophil lipocalin (HNL) are proteins which are stored in neutrophil granulocytes, in the primary and secondary granules, respectively. These granules or their contents of MPO and HNL are secreted upon activation of the cells, and measurement of these soluble markers in biological fluids, such as bronchoalveolar lavage (BAL), has been proposed to mirror the degree of neutrophil activity in the tissue. We conducted a BAL study in 10 healthy volunteers, with the aim to evaluate the intra-individual variability of the concentration of HNL and MPO recovered in sequential aspirations, during a time period when the concentrations of HNL and MPO in BAL fluids were considered to have equilibrated with those in the underlying tissues. The concentrations of HNL were less variable than those of MPO (coefficients of variability 0.33 +/- 0.07 vs. 0.92 +/- 0.28; P = 0.01), suggesting HNL to be a more useful marker of neutrophil activity within the airspace. The specificity of HNL as a selective index of neutrophil cells was confirmed by means of immunohistochemical staining of uninvolved lung tissue specimens obtained from patients referred to pulmonectomy due to carcinoma. While HNL was located only to intracellular spaces of neutrophils, MPO was in addition located to other cells as well. We speculate that the dynamic changes of pressure across the membranes and flow of solutes during a lavage process might mobilize particulate matter and adherent cells, some of which may be loaded with MPO, and that this may introduce larger variability in the recovery of MPO than of HNL. We conclude that using HNL as a soluble indicator of neutrophil presence is more feasible than using MPO.

Stereoselective pharmacokinetics of S-salbutamol after administration of the racemate in healthy volunteers

Racemic R,S-salbutamol is taken to relieve bronchial constriction. Only the R-enantiomer has bronchodilating properties. The S-enantiomer has been proposed to cause in vitro bronchial hyperreactivity in guinea-pigs. Stereoselective elimination of salbutamol has been shown, with S-salbutamol being eliminated at a slower rate than R-salbutamol. This study questioned whether rates of stereoselective elimination were similar after oral or lung delivery, and whether the S:R ratio would increase after repeated inhalations in a situation resembling a common clinical use. Eighteen healthy volunteers received single-dose racemic salbutamol as a solution instilled in the trachea during anaesthesia, as inhaled micronized powder and/or as ingested tablets. Five volunteers inhaled repeated doses of racemic salbutamol. Concentrations in plasma and urine were measured using a technique which allowed chiral separation of samples with concentrations as low as 0.1 ng x mL(-1). The bioavailability of S-salbutamol was significantly higher than that of R-salbutamol after the different modes of administration. Stereoselective elimination was more pronounced after oral administration than after inhalation. Repeated inhalations resulted in successive increases in the S:R ratio as steady state was approached. In conclusion, the clinical consequences of increasing plasma concentrations of S-salbutamol need to be further assessed.

The diagnostic capacity of forced oscillation and forced expiration techniques in identifying asthma by isocapnic hyperpnoea of cold air

The measurement of forced expiratory volume in one second (FEV1) is often used to assess the effect of bronchial provocations, and deep inspiration is required beforehand. This may briefly alter the bronchial tone in a variable way in some subjects. The forced oscillation technique (FOT) is a test used to characterize the mechanical impedance of the respiratory system, and prior deep inspiration is not required. We tested the hypothesis that measurable bronchoconstriction would occur in all asthmatic subjects stimulated with isocapnic hyperventilation of dry cold air (IHCA). Twenty patients with mild asthma and nine healthy controls were exposed to IHCA, at 70% of their maximal voluntary ventilatory capacity for 4 min and the results were assessed both by applying the FOT and by measuring FEV1. Optimal cut-off levels were defined by receiver operating characteristic (ROC) curve analyses of the changes in respiratory resistance and reactance at 5-35 Hz, resonant frequency (fres) and FEV1. A positive result was present in the asthmatics when measured by FOT, and using ROC analyses the discriminative capacity to correctly diagnose asthma was greatest for responses in fres; the sensitivity was 89% and the specificity 100%. The sensitivity of FEV1 to correctly diagnose asthma was only 73%, and the specificity 88%. In conclusion, the results of this study suggest that the use of forced expiratory volume in one second for bronchial provocation tests by isocapnic hyperventilation of dry cold air may be misleading and that the bronchoconstriction thus elicited is measured with greater sensitivity and specificity by the forced oscillation technique than by forced expiratory volume in one second.

Relative effects of inhaled corticosteroids on immunopathology and physiology in asthma: a controlled study

BACKGROUND

Although corticosteroids are recognised as the most efficacious treatment for bronchial asthma, their mode of action remains unclear. A placebo controlled trial was undertaken of the effect of inhaled corticosteroids on physiological and immmunopathological parameters in asthmatic patients in whom the correlations between these indices were tested after treatment.

METHODS

Sixteen patients (two women) with asthma entered a double blind, placebo controlled, parallel study during which they inhaled either budesonide 800 micrograms twice daily or matching placebo for six weeks. Spirometric parameters and bronchial reactivity to histamine and terbutaline were measured and endobronchial biopsy samples were taken before and after treatment. Patients recorded morning and evening flow rates during the treatment period. The biopsy samples were subjected to immunohistological analysis to determine the disposition of inflammatory cells within the bronchial wall.

RESULTS

Treatment with budesonide resulted in a significant improvement in the 25-75% forced expiratory flow (FEF25-75) from a mean of 133 l/min before treatment to 169 l/min after treatment, and in the morning peak expiratory flow rate (PEFR) from a mean of 384 l/min before treatment to 415 l/min after treatment. No changes were seen in the placebo group. Comparison between the changes in the immunopathological indices after six weeks of treatment with placebo or budesonide showed a significant reduction in the numbers of mast cells (0.5/unit area to 0.2/ unit area), activated eosinophils, and the expression of HLA-DR antigens (relative density -1.9 before to 1.02 after treatment) on inflammatory cells in response to treatment with budesonide. Although reductions in the numbers of other inflammatory cells within the bronchial wall were recorded using immunohistological analysis, these changes were not statistically significant. Significant correlations were found between changing immunological indices and lung physiology.

CONCLUSIONS

This controlled study shows that inhaled corticosteroids cause improvement in physiological and immunopathological parameters in patients with stable asthma that are not seen with placebo, and that cause and effect relationships may exist between these two measures of disease status.

Early and late allergic skin reactions in T cell deficient patients

Impaired delayed type skin sensitivity is supposed to be due to abnormalities in T lymphocyte functions. Lately it has been assumed that T cells play an important part also in the development of late allergic reactions in the skin and in the lungs. Patients with sarcoidosis, lung carcinoma or with uremia were skin tested with anti IgE antibodies to challenge the hypothesis that the same sort of T cell deficiency as impaired the delayed skin sensitivity also attenuated the late allergic skin reactions. All patients obtained an early reaction and with a size similar to that of normal controls. In most of the patients late reactions were seen, but the frequency varied between 67% for patients with uremia and 100% for those with sarcoidosis. The cancer patients had significantly smaller late reactions than the normal controls while patients with uremia or sarcoidosis had a normal size of their reaction. No correlation could be found between delayed reactions to PPD and late reactions to anti IgE. It is concluded that the type of lymphocyte abnormality giving impaired delayed type reactivity in e.g. sarcoidosis patients does not affect the allergic early or late skin reactivity. Testing for late allergic reactivity may be a new tool for evaluating the immune status of, for example, cancer patients.

Increased adhesion to vascular cell adhesion molecule-1 and intercellular adhesion molecule-1 of eosinophils from patients with asthma

Adhesion of peripheral blood eosinophil and neutrophil granulocytes to the endothelial cell adherence receptors E-selectin, vascular cell adhesion molecule-1, and intercellular adhesion molecule-1 has been measured. The study included patients with allergic rhinitis, patients with mild allergic and nonallergic asthma, and healthy individuals; 10 persons were in each group. In addition, assay of eosinophil and neutrophil cell surface expression of the receptor complex CD11b/CD18 was performed. Increased eosinophil adhesion to vascular cell adhesion molecule-1 (p < 0.05) and intercellular adhesion molecule-1 (p < 0.05) was demonstrated in the patients with a more labile asthma, that is, a peak expiratory flow rate variability of more than 10%, suggesting a relationship to the degree of ongoing inflammation in the airways of the patients. The increased eosinophil adhesion was most probably due to a functional upregulation of the CD11b/CD18 and very late activation antigen-4 receptors, because the number of receptors measured as cell surface expression was unaltered. The increased eosinophil adhesion in the patients with high peak expiratory flow rate variability appeared independent of atopy. The increased adhesion was not entirely specific to the eosinophils, because neutrophils from patients with a peak expiratory flow rate variability of more than 10% also demonstrated increased adhesion to intercellular adhesion molecule-1 (p < 0.05) when compared with neutrophils from the patients with low peak expiratory flow rate variability. In conclusion, the demonstrated priming of eosinophil adhesion to vascular cell adhesion molecule-1 and intercellular adhesion molecule-1 might be one contributing mechanism behind the selective accumulation of eosinophils in the lung tissue of patients with asthma.

Kinetic retrieval of eosinophil cationic protein, hyaluronan, secretory IgA, albumin, and urea during BAL in healthy subjects

Determination of absolute concentrations of various soluble components of the epithelial lining fluid (ELF) may be valuable to estimate inflammatory activities within the underlying lung tissue. Internal standards may then be used as markers of dilution of bronchoalveolar lavage (BAL). The aim of this study was to determine whether different dwell times would affect the relationship between the concentrations of any of the three potential internal standards (secretory IgA [SIgA], albumin, and urea), and the concentrations of two potential markers of inflammation (eosinophil cationic protein [ECP] and hyaluronan [HA]) in BAL. A series of aliquots of BAL fluid were aspirated every 60 s up to 8 min after a bolus instillation of saline solution in 20 healthy subjects (10 smokers). The BAL concentrations of albumin and urea increased with time, consistent with continuous diffusion from the body water pool, absorption of the BAL fluid, or both. The rate constant of diffusion was 1,000 times higher for urea than for albumin (3.38 x 10(-1) and 3.64 x 10(-4), respectively), reflecting the difference in molecular weights, and in agreement with the notion that albumin and urea appeared in BAL fluid by a rate-limited procedure related to osmotic transfer. Biexponential increases of SIgA were recorded, suggesting a two-compartmental origin of this compound, normally located to mucosal membranes and presumed to be dissolved in ELF. Time-dependent increases in BAL fluid of HA also were recorded, but on the other hand, the ECP concentrations tended to level off after an initial increase, suggesting that the bulk of ECP appeared in BAL by a nonosmotic mechanism. We conclude that the kinetics of these three internal standards in BAL fluid differs greatly from each other and from the kinetics of the two selected markers of inflammation. Consequently, internal standards for determination of absolute concentrations of markers of inflammation in ELF should be carefully selected because of the requirement of matched kinetics of the markers.

The bronchial response, but not the pulmonary response to inhaled methacholine is dependent on the aerosol deposition pattern

The clinical effect of inhaled radio-labeled (Technetium-99m diethylenetriamine-pentaacetic acid) methacholine was studied in two separate experiments performed in eight symptom-free asthmatics with bronchial hyperresponsiveness. Aerosols were formed by two different nebulizers, producing either mainly small aerosol particles (2-microns mass median aerodynamic diameter [MMAD]) for peripheral, or mainly large aerosol particles (9-microns MMAD) for large airway deposition. The intended site of deposition was confirmed by gamma camera recordings. Changes in specific airway conductance (sGaw) were set as an index of central airway constriction, and functional alterations in the gas exchanging parts of the lung were estimated by multiple inert gas elimination technique (MIGET) and arterial blood gas analyses. The main finding was that the responses, as measured by the changes in arterial blood gases and by MIGET, were similar in the two experiments, while the fall in sGaw was significantly larger after deposition in the main bronchi than in the peripheral airways (p < 0.05). The time courses of the abnormalities in the gas exchanging elements were much longer than those of the responses of the central airways, and the abnormalities were recorded still at the end of the experiment 2 h after challenge in most patients. A discrepancy in dose dependency and time courses suggests differences in mechanism and/or dynamics of the responses exerted by the various target organs. Interaction in the process of clearance from the lung of inhaled methacholine by the bronchial circulation may have contributed to the observed discrepancies.

Tremor in healthy volunteers after bambuterol and terbutaline CR-tablets

Bambuterol tablets, 10 and 20 mg, and terbutaline CR-tablets, 5 and 7.5 mg, have been compared for their capacity to produce subjectively determined tremor in a randomised, double-blind, cross-over study in 40 healthy volunteers. The duration of each treatment was one week, with an intervening washout period of at least 2 weeks. On the second and the last treatment days in each period, tremor was subjectively assessed on six occasions. In addition, an overall assessment of night and day tremor was made each morning and evening. Analyses were made for the second and last treatment days and during the treatment week. Paired comparisons for tremor during daytime showed a significant difference between the treatments, with the exception of bambuterol 20 mg and terbutaline 5 mg. Bambuterol 10 mg caused less tremor and terbutaline 7.5 mg caused more tremor than the other treatments. At the end of the week, the differences were smaller and were only significant when comparing bambuterol 10 mg with the 20 mg dose and with high dose terbutaline. Terbutaline 7.5 mg caused more tremor at night than the other treatments. The tremor experienced was generally mild, and after bambuterol 10 mg it was almost negligible (mean 0.13 after the first dose). Two subjects recorded a score of 3 after terbutaline 7.5 mg. The results indicate that, in doses equipotent with regard to bronchodilation, tremor is less pronounced after bambuterol as compared to controlled release tablets of terbutaline.

Determination of theophylline in plasma using different capillary electrophoretic systems

Theophylline was determined in human plasma by capillary electrophoresis (CE). The drug was used as a model substance to study a simple sample pretreatment often used in HPLC: to 200 microliters of plasma were added 400 microliters of acetonitrile to precipitate the plasma proteins and the supernatant was injected into the capillary after centrifugation. Three capillary electrophoretic systems were compared with respect to migration time and electrophoretic migration reproducibility. UV detection at 280 nm was applied. The separation was preferably made in an uncoated fused-silica capillary (57 cm x 75 microns I.D.) with 10 mM phosphate-borate buffer (pH 9.0) as the electrophoretic buffer. A linear calibration graph was obtained in the concentration range studied, 1.8-36 micrograms/ml (10-200 microM). The method permits the determination of theophylline in plasma at therapeutic concentrations of 4.5-20 micrograms/ml (25-110 microM) with acceptable precision.

Markers for eosinophils and T-lymphocytes as predictors of late asthmatic response

Bronchial allergen challenge was performed on 12 allergic asthmatics during a stable phase of their disease. After resolution of the immediate bronchial response, fractional lung lavage was performed twice, two and 24 h post-challenge. The recovery of eosinophils, eosinophil cationic protein (ECP), eosinophil chemotactic activity (ECA) and immunohistochemical staining of the phenotypically distinct population stainable by the monoclonal antibody CD45RO, agreed to indicate T-memory cells, were assessed in the two lavages. Serial measurements of lung function, and serum concentration of ECP were also done. We found that although the recoveries in bronchial washes of eosinophil cells and ECP tended to increase during the trial, none of these variables predicted the emergence of late phase bronchial response (LPR). Instead, the proportion in the 2-h lavages, of memory-cells or ECA predicted the LPR. These two variables were inversely correlated to each other in the first lavage, suggesting the T-cells to be potential major sources of ECA. The fact that T-cells and ECA, but not markers for eosinophil activation in lavage, predicted the LPR, may suggest T-cell activation to precede the activation of the eosinophils within the lung after a bronchial allergen challenge. There was a close correlation between LPR and serum concentration of ECP obtained at the end of the trial, 24 h post-challenge, suggesting either a delayed or a continuous activation of circulating eosinophils after bronchial allergen challenge.

[Current aspects of asthma]

Knowledge of the pathophysiology and aetiology of asthma has expanded greatly during recent years, and hopes are strong that within the foreseeable future it will be possible to alleviate asthmatic symptoms even more effectively. This review covers some of this new knowledge, and presents viewpoints on the practical clinical management of asthma patients.

Integrity of the alveolar-capillary barrier and alveolar surfactant system in smokers

BACKGROUND

The permeability of the alveolar-capillary barrier to technetium-99m labelled diethylenetriamine pentaacetate (99mTc DTPA) is known to be greatly increased in smokers, but the underlying mechanism is poorly understood. Abnormal permeability of the alveolar epithelium as well as impaired surfactant function has been suggested. The purpose of this study was to examine transudation of urea and albumin into the alveoli and alveolar surfactant function in smokers and non-smokers and to relate these variables to the rate of alveolar-capillary transfer of 99mTc DTPA.

METHODS

Standardised bronchoalveolar lavage was performed and the yield of urea and albumin measured in the lavage fluid. The integrity of the alveolar surfactant system was assessed by measurement of the surface activity and of the yield of phospholipids in alveolar lavage fluid.

RESULTS

The mean decay constant for the pulmonary clearance of 99mTc DTPA was 0.028/min in the smokers and 0.009/min in the non-smokers. The recovery of albumin and urea in alveolar lavage fluid was very similar in the two groups. The surface activity of alveolar lavage fluid was lower in smokers than in non-smokers (minimum surface tension 37.9 versus 28.6 mN/m) and the yield of phospholipids was reduced (2.08 versus 3.86 mg). The rate constant for the pulmonary clearance of 99mTc DTPA correlated with the yield of phospholipids at bronchoalveolar lavage.

CONCLUSIONS

The study shows that increased alveolar-capillary transfer of 99mTc DTPA in smokers is not accompanied by increased transudation of small or large molecules into the alveoli. The findings support the hypothesis that increased clearance of 99mTc DTPA in smokers is related to surfactant dysfunction.

Exercise increases the rate of pulmonary absorption of inhaled terbutaline

The purpose of the study was to investigate whether a constant submaximal exercise challenge affected the plasma pharmacokinetics of an inhaled beta 2-adrenoceptor agonist, terbutaline sulfate. Eight healthy nonsmokers participated in a study comprising measurements of plasma concentrations of terbutaline on two separate study days. Plasma samples were frequently collected at rest during study day 1, and on the second study day, during and after a 30-min exercise challenge, which was performed immediately after inhalation of the drug. The rate of increase of plasma concentrations and the maximal plasma concentrations were higher during exercise than during rest (p less than 0.01 and p less than 0.05, respectively). The plasma concentration fell rapidly after cessation of the exercise and approached those obtained at rest. We suggest that increased pulmonary and/or bronchial blood flow and altered surface tension of the liquid lining of the air space may contribute to the enhancement of absorption of this hydrophilic compound during exercise. Based on the levels of the maximal plasma concentrations reached during exercise in this study, the results would be to increase the frequency of administration of the drug, rather than to increase the administered doses, if the aim is to prevent or ameliorate exercise-induced asthma and potential systemic side effects.

T-cell dominated inflammatory reactions in the bronchi of asthmatics are not reflected in matched bronchoalveolar lavage specimens

Samples of bronchoalveolar lavage (BAL) and endobronchial biopsies were obtained from five patients with clinically diagnosed asthma (ATS criteria). A comparison was made of the presence and distribution of immunocompetent lymphocytes and macrophages within each sample. Significantly raised numbers of T lymphocytes, CD45RO+ lymphocytes, RFD1+ macrophage-like cells and RFD7+ macrophages were seen in the bronchial biopsies. In contrast four out of five of the BAL specimens showed a normal differential cell count, the one exception being a patient exhibiting a degree of lymphocytosis. Further, immunocytological investigation demonstrated a normal distribution of T-cell subsets and macrophage subsets in asthmatic BAL with the exception that in four out of five of these patients a raised number of macrophage-like cells exhibiting phenotypic markers of monocytes was observed. Correlation between BAL and biopsy data was seen in the number of CD45RO+ T-cells present. No other parameters exhibited a significant correlation. Raised expression of HLA-DR was recorded in all asthmatic biopsies, yet lavage cells from the same patients failed to exhibit any increase of HLA-DR density over normal. It is concluded that the immune-associated inflammation present in endobronchial biopsies of clinically stable asthmatics is not reflected in bronchoalveolar lavage samples taken from the same patients.

T-cell dominated inflammatory reactions in the bronchi of asthmatics are not reflected in matched bronchoalveolar lavage specimens

Samples of bronchoalveolar lavage (BAL) and endobronchial biopsies were obtained from five patients with clinically diagnosed asthma (ATS criteria). A comparison was made of the presence and distribution of immunocompetent lymphocytes and macrophages within each sample. Significantly raised numbers of T lymphocytes, CD45RO+ lymphocytes, RFD1+ macrophage-like cells and RFD7+ macrophages were seen in the bronchial biopsies. In contrast four out of five of the BAL specimens showed a normal differential cell count, the one exception being a patient exhibiting a degree of lymphocytosis. Further, immunocytological investigation demonstrated a normal distribution of T-cell subsets and macrophage subsets in asthmatic BAL with the exception that in four out of five of these patients a raised number of macrophage-like cells exhibiting phenotypic markers of monocytes was observed. Correlation between BAL and biopsy data was seen in the number of CD45RO+ T-cells present. No other parameters exhibited a significant correlation. Raised expression of HLA-DR was recorded in all asthmatic biopsies, yet lavage cells from the same patients failed to exhibit any increase of HLA-DR density over normal. It is concluded that the immune-associated inflammation present in endobronchial biopsies of clinically stable asthmatics is not reflected in bronchoalveolar lavage samples taken from the same patients.

Lung function and immunopathological changes after inhaled corticosteroid therapy in asthma

Six patients with asthma (American Thoracic Society (ATS) criteria), maintained on inhaled beta 2-agonists alone, were treated with inhaled corticosteroid (budesonide 400 micrograms b.d.) for a period of three months. Prior to steroid therapy, baseline spirometry, bronchodilator response and bronchial hyperresponsiveness were documented and endobronchial biopsies were obtained for immunopathological analysis. Frozen sections of the biopsies were investigated using immunoperoxidase methods, with a panel of monoclonal antibodies selected to reveal the presence and distribution of lymphocyte and macrophage subsets and HLA-DR expression. After three months the studies were repeated. Studies before steroid therapy revealed a T-cell-dominated inflammation in the bronchial wall of all subjects. Baseline airway obstruction, median (range) forced expiratory volume in one second (FEV1) 78.5 (61-109)% of predicted, with a significant bronchodilator response 20.8 (14-33)% and bronchial hyperresponsiveness to histamine geometric mean (SD) PC20FEV1 0.69 (2.5) mg was documented. Steroid therapy caused a significant reduction in bronchial hyperresponsiveness to histamine, with an increase in geometric mean PC20FEV1 to 2.22 (3.2) mg post steroid (p less than 0.03). Concurrent with a reduction in bronchodilator response and an increase in spirometric variables (improved forced midexpiratory flow (FEF25-75) p less than 0.03), there were marked reductions observed in the overall numbers of T-lymphocytes (CD 2, 5, 8), the numbers of CD45RO+ T-cells, and the numbers of macrophages (RFD1+) with the phenotype of antigen presenting cells. In all six subjects, reductions in the quantitative expression of HLA-DR molecules were also seen.(ABSTRACT TRUNCATED AT 250 WORDS)

Increased eosinophil chemotactic activity in bronchial washes obtained from patients with asymptomatic allergic alveolitis

The chemotactic activities of eosinophils and neutrophils were measured in bronchial washes obtained from 6 symptom-free patients with previous extrinsic allergic alveolitis and 9 healthy volunteers. An increased chemotactic activity was found in the washes obtained from the patients, and the recovery of eosinophils was correlated with the eosinophil chemotactic activity, suggesting a causal relationship. Chromatography of the fluids obtained suggested that low molecular weight compounds were principally responsible for the increased chemotactic activity. A mild disturbance of the integrity of the alveolocapillary barrier could to some extent add to the explanation of the increased chemotactic activity in the washes obtained from the patients.

Lung function and immunopathological changes after inhaled corticosteroid therapy in asthma

Six patients with asthma (American Thoracic Society (ATS) criteria), maintained on inhaled beta 2-agonists alone, were treated with inhaled corticosteroid (budesonide 400 micrograms b.d.) for a period of three months. Prior to steroid therapy, baseline spirometry, bronchodilator response and bronchial hyperresponsiveness were documented and endobronchial biopsies were obtained for immunopathological analysis. Frozen sections of the biopsies were investigated using immunoperoxidase methods, with a panel of monoclonal antibodies selected to reveal the presence and distribution of lymphocyte and macrophage subsets and HLA-DR expression. After three months the studies were repeated. Studies before steroid therapy revealed a T-cell-dominated inflammation in the bronchial wall of all subjects. Baseline airway obstruction, median (range) forced expiratory volume in one second (FEV1) 78.5 (61-109)% of predicted, with a significant bronchodilator response 20.8 (14-33)% and bronchial hyperresponsiveness to histamine geometric mean (SD) PC20FEV1 0.69 (2.5) mg was documented. Steroid therapy caused a significant reduction in bronchial hyperresponsiveness to histamine, with an increase in geometric mean PC20FEV1 to 2.22 (3.2) mg post steroid (p less than 0.03). Concurrent with a reduction in bronchodilator response and an increase in spirometric variables (improved forced midexpiratory flow (FEF25-75) p less than 0.03), there were marked reductions observed in the overall numbers of T-lymphocytes (CD 2, 5, 8), the numbers of CD45RO+ T-cells, and the numbers of macrophages (RFD1+) with the phenotype of antigen presenting cells. In all six subjects, reductions in the quantitative expression of HLA-DR molecules were also seen.(ABSTRACT TRUNCATED AT 250 WORDS)

Recoveries of phosphatidylcholine and alveolar macrophages in lung lavage from healthy light smokers

Twenty-one healthy volunteers, 11 light smokers and 10 non-smokers, were studied by broncho-alveolar lavage. The levels of the phosphatidylcholine (PC) in broncho-alveolar lavage were measured and used as an index of surfactant. The PC levels in broncho-alveolar lavage obtained from the smokers were significantly lower than in lavage fluid from the non-smokers. There was an inverse correlation between PC levels and cumulated tobacco smoke exposure, as estimated by the number of pack-years, and to current smoking habits as estimated by the number of cigarettes smoked per day. The number of alveolar macrophages was significantly higher in broncho-alveolar lavage obtained from smokers, and there was a significant inverse correlation between PC levels and numbers of alveolar macrophages in the lavage fluids. The potential role of alveolar macrophages in the elimination of surfactant lipids is discussed.

T cell dominated inflammatory reactions in the bronchioles of asymptomatic asthmatics are also present in the nasal mucosa

Endobronchial and nasal mucosa biopsies were obtained from 5 patients with clinically-stable, diagnosed asthma (ATS criteria). A comparison was made of the presence and distribution of immunocompetent lymphocytes and macrophages within each sample. The distribution of immunocompetent cells within the nasal biopsies of the asthmatic patients reflected a very similar inflammatory infiltrate to that seen in the bronchial biopsies. Significantly raised numbers of T lymphocytes, CD45RO + lymphocytes, RFD1 + macrophage-like cells and RFD7 + macrophages were seen in both the nasal mucosa and the bronchial biopsies. Increases in HLA-DR expression were also seen in the nasal mucosa biopsies from asthmatics although the increases over normal did not reach statistical significance. It is concluded that inflammation present in the nasal mucosa of asymptomatic asthmatics exhibits cellular characteristics also seen in endobronchial biopsies. This observation offers the possibility that mucosal biopsy may be an alternative and less invasive approach for studying the cells involved in the bronchial inflammatory reaction that possibly predisposes asthmatics to bronchial hyper-responsiveness.

Granulocytes and their secretory products, myeloperoxidase and eosinophil cationic protein, in bronchoalveolar lavage fluids from two lung lobes in normal subjects

The interlobar variability of lavage neutrophils and eosinophils was studied in twelve healthy subjects. In addition, the interlobar variation of the neutrophil cell marker myeloperoxidase (MPO) and the eosinophil cell marker eosinophil cationic protein (ECP) was assessed. Bronchial washes (BW), as defined by the first aspirated lavage aliquot, and bronchoalveolar lavage (BAL) fluids were compared. One subsegment of the right middle lobe and one subsegment of the right lower lobe were lavaged in the same session. Interlobar consistency of neutrophil and eosinophil cell recoveries was observed but, in contrast, the levels of MPO or ECP did not correlate in lavage fluids aspirated from the two lobes. These results suggest that BAL cell content from a single lobe of the lung in healthy subjects does reflect the cell populations throughout the airways, while the levels of soluble proteins may differ between the lobes. Such a variation questions the correlation between cells and their secretory products or the correlation between levels of solutes in lavage fluid and in the underlying tissue. Further methodological studies appear warranted to elucidate whether cell and solute recoveries accurately reflect the underlying pathology.

Granulocytes and their secretory products, myeloperoxidase and eosinophil cationic protein, in bronchoalveolar lavage fluids from two lung lobes in normal subjects

The interlobar variability of lavage neutrophils and eosinophils was studied in twelve healthy subjects. In addition, the interlobar variation of the neutrophil cell marker myeloperoxidase (MPO) and the eosinophil cell marker eosinophil cationic protein (ECP) was assessed. Bronchial washes (BW), as defined by the first aspirated lavage aliquot, and bronchoalveolar lavage (BAL) fluids were compared. One subsegment of the right middle lobe and one subsegment of the right lower lobe were lavaged in the same session. Interlobar consistency of neutrophil and eosinophil cell recoveries was observed but, in contrast, the levels of MPO or ECP did not correlate in lavage fluids aspirated from the two lobes. These results suggest that BAL cell content from a single lobe of the lung in healthy subjects does reflect the cell populations throughout the airways, while the levels of soluble proteins may differ between the lobes. Such a variation questions the correlation between cells and their secretory products or the correlation between levels of solutes in lavage fluid and in the underlying tissue. Further methodological studies appear warranted to elucidate whether cell and solute recoveries accurately reflect the underlying pathology.

Glucocorticoid receptor mRNA expression in pulmonary alveolar macrophages in sarcoidosis

The presence of the glucocorticoid receptor was demonstrated by immunocytochemistry in pulmonary alveolar macrophages obtained by bronchoalveolar lavage. Also, GR mRNA content was determined by solution hybridization in PAM from 12 healthy volunteers and in 6 patients with sarcoidosis. No significant differences with regard to GR mRNA expression was detected between the two groups examined. For comparison, lung tissue from three patients undergoing thoracic surgery was examined and found to contain GR mRNA levels in the same range. As an indication of GR function, we also determined the mRNA levels of a glucocorticoid-regulated gene, metallothionein IIA, during basal conditions and after in vitro incubation of PAM with dexamethasone. Neither the control sample nor the dexamethasone-stimulated MTII mRNA values in PAMs differed significantly between the two groups. Solution hybridization is a rapid, sensitive and convenient assay which enables accurate and specific quantitation of GR mRNA in PAM. The GR mRNA content and basal as well as dexamethasone-induced MTII mRNA levels in PAM from patients with sarcoidosis is not significantly different from those in healthy volunteers.

The distribution of myeloperoxidase, eosinophil cationic protein, albumin and urea in sequential bronchoalveolar lavage

The distribution of myeloperoxidase (MPO) and eosinophil cationic protein (ECP), secreted from activated neutrophils and eosinophils, was estimated in bronchoalveolar lavage fluid in a sequential lavage study performed on 12 healthy subjects. Four 50 ml aliquots were sequentially injected into the right middle lobe and immediately aspirated. Recent studies, using radiological methods, have revealed proximal airway distribution of the first infused lavage aliquot, and more peripheral distribution of the following ones. We found significantly higher concentrations of MPO (p less than 0.001) and ECP (p less than 0.001) in the first aspirated aliquots as compared to the following three. These findings are compatible with the concept that these substances are, to a substantial part, distributed to the surface of the proximal airways. In contrast, the sequential recovery of albumin and urea showed a homogeneous recovery pattern. The findings were compatible with those of a small series of sixteen 10 ml lavage aliquots, sequentially infused and aspirated, also indicating a continuous diffusion of these small molecules through the lung membranes into the lavage fluid during the lavage process. We conclude that the difference in recovery pattern and distribution on the bronchial surface makes albumin and urea unsuitable as denominators in ratios to MPO and ECP, for the estimation of quantitative local concentration in epithelial lining fluid.

The distribution of myeloperoxidase, eosinophil cationic protein, albumin and urea in sequential bronchoalveolar lavage

The distribution of myeloperoxidase (MPO) and eosinophil cationic protein (ECP), secreted from activated neutrophils and eosinophils, was estimated in bronchoalveolar lavage fluid in a sequential lavage study performed on 12 healthy subjects. Four 50 ml aliquots were sequentially injected into the right middle lobe and immediately aspirated. Recent studies, using radiological methods, have revealed proximal airway distribution of the first infused lavage aliquot, and more peripheral distribution of the following ones. We found significantly higher concentrations of MPO (p less than 0.001) and ECP (p less than 0.001) in the first aspirated aliquots as compared to the following three. These findings are compatible with the concept that these substances are, to a substantial part, distributed to the surface of the proximal airways. In contrast, the sequential recovery of albumin and urea showed a homogeneous recovery pattern. The findings were compatible with those of a small series of sixteen 10 ml lavage aliquots, sequentially infused and aspirated, also indicating a continuous diffusion of these small molecules through the lung membranes into the lavage fluid during the lavage process. We conclude that the difference in recovery pattern and distribution on the bronchial surface makes albumin and urea unsuitable as denominators in ratios to MPO and ECP, for the estimation of quantitative local concentration in epithelial lining fluid.

Difference in pulmonary absorption of inhaled terbutaline in healthy smokers and non-smokers

Pathophysiological studies have shown that the alveolocapillary transfer of small solutes is much faster in healthy smokers than in non-smokers. The effects of smoking on the pulmonary absorption of inhaled terbutaline were examined in normal subjects. Nine healthy smokers and 13 healthy non-smokers inhaled nebulised terbutaline and dry terbutaline powder on two study days. Plasma concentrations of terbutaline were measured up to 240 minutes after the inhalation. The plasma concentration of terbutaline rose much faster in smokers than in non-smokers, the mean time to peak terbutaline concentration being 17 minutes in the smokers and 50 minutes in the non-smokers. The peak plasma concentration was nearly twice as high in the smokers as in the non-smokers, being 21 mmol/l and 23 mmol/l for the dry powder inhalation and nebuliser respectively in the smokers and 12 mmol/l and 14 mmol/l in the non-smokers. It is concluded that smoking increases the rate of terbutaline absorption and the peak plasma concentration achieved. The rapid pulmonary absorption of terbutaline in smokers may affect the onset of action of the drug and the duration of its therapeutic effects.

Myeloperoxidase in human lung lavage. I. A marker of local neutrophil activity

The origin of myeloperoxidase (MPO) in bronchoalveolar lavage (BAL) was investigated in the first part of the study. Radioimmunoassay of the cellular and supernatant MPO content as well as the peroxidase-antiperoxidase (PAP) technique were employed to determine the cellular source of MPO. The concentrations of MPO were measured in serum and BAL in the second part of the study. The aim was to determine whether the capillary bed was also a source of MPO. Neutrophil numbers in BALs obtained from 20 healthy subjects correlated significantly to the concentrations of MPO in cell-free BAL supernatants (r = 0.643, P less than or equal to 0.01). The cellular content of MPO in mixed BAL cells was significantly correlated to the number of neutrophils in the mixture (r = 0.536, P less than 0.05), but not to the number of any other cells. Moreover, the PAP-technique identified MPO in lung tissue neutrophils in resection specimens obtained from three patients undergoing surgery. This technique also revealed strong MPO activity in all BAL neutrophils and a weak activity in merely 4% of the alveolar macrophages in cytospin preparations obtained from seven BALs. High BAL/serum ratio of MPO concentrations suggests that MPO is of local origin, rather than passively diffused from the circulating pool. We therefore conclude that strong evidence suggests that MPO in BAL originates from lung neutrophils and that BAL MPO content may be used to estimate the neutrophil presence or activation in epithelium lining fluid.

Myeloperoxidase in human lung lavage. II. Internalization of myeloperoxidase by alveolar macrophages

Bronchial wash and bronchoalveolar lavage were performed in 12 healthy subjects (five smokers), in order to elucidate whether or not material of neutrophil origin may be phagocytized by lung macrophages in vivo. Cells from different levels in the bronchial tree were obtained by sequential injection and subsequent aspiration of either four 50-ml or five 10-ml aliquots. Each aliquot was used for the determination of total and differential cell counts. The proportion of myeloperoxidase-positive alveolar macrophages was determined by specific immune histochemical staining. The percentage of myeloperoxidase-positive macrophages was highest (median 94.8%, range 37-98.5%) in the 10-ml aliquots and lowest in the last three 50-ml aliquots (median values 1-2.5%) (P less than 0.001). A significant correlation was obtained between the fraction of myeloperoxidase-positive macrophages and the percentage count of bronchoalveolar lavage neutrophils (r = 0.466, P less than 0.05). Furthermore, the cellular myeloperoxidase showed a significant inverse correlation (r = -0.46, P less than 0.05) to the viability of the bronchoalveolar lavage cells. Our findings are compatible with previous demonstrations in animals of neutrophil phagocytosis by lung macrophages and show that this phenomenon in particular occurs in the more proximal airways. The internalization of neutrophils or neutrophil components by airway macrophages may be an important scavenger mechanism for protection of the lung from the deleterious effects of activated neutrophils.

Transfer of 99mTc DTPA and bronchoalveolar lavage findings in patients with asymptomatic extrinsic allergic alveolitis

An investigation was performed to determine whether symptom free patients with previously diagnosed extrinsic allergic alveolitis had signs of inflammation in the lung. Pulmonary clearance of inhaled technetium-99m labelled diethylene triamine penta-acetic acid (DTPA) was measured in seven patients with a history of extrinsic allergic alveolitis but with no symptoms at the time of the study and in 12 control subjects. Monoexponential clearance curves were obtained in all 12 control subjects. In contrast, lung clearance was abnormal in five of the seven patients: biexponential clearance curves were noted in four and an abnormally rapid monoexponential curve in one. Bronchoalveolar lavage was performed in all patients. Fluid from the second and third aliquots showed increased concentrations of albumin and urea in fluids from the patients, suggesting increased plasma leakage through the alveolocapillary membranes. More eosinophils and more eosinophil cationic protein were also found in the lavage fluid from the patients. The trend towards increased numbers of eosinophils in patients with abnormal lung clearance of DTPA suggests that this may be due to a continuing inflammatory reaction. Lung inflammation was also suggested by the fact that less leukotriene B4 was secreted by cultured alveolar macrophages obtained from patients than by control macrophages. It is concluded that symptom free patients with previous extrinsic allergic alveolitis have continuing alveolar disease as shown by lung clearance and lavage findings.

Extensive surgery for left atrial leiomyosarcoma diagnosed by echocardiography. A case report

A case of malignant leiomyosarcoma presenting as a left atrial cardiac tumor is described and its echocardiographic features are discussed. Tumor masses invading the atrial walls were extensively resected and the atrial wall was reconstructed with two patches of bovine pericardium.

C3b receptor-mediated phagocytosis in sarcoidosis with extra-thoracic manifestations

Two groups of sarcoidosis patients were studied. One group of 24 patients had previously had erythema nodosum (EN+), and the other group of 54 patients had never had any such extrathoracic manifestation of the disease (EN-). The two groups were similar with respect to age, disease duration, chest radiographic appearance, and granuloma mass as estimated from the serum concentration of lysozyme. Neutrophil phagocytic function was studied by a kinetic method which allows distinction between Fc- and C3b-receptor-mediated uptake. Fc-receptor function was normal in both groups. The function of C3b receptors was normal in the EN+ groups but significantly reduced in the EN- group. This observation indicates that sarcoidosis associated with erythema nodosum may represent a separate disease entity with respect to the pathogenetic mechanism involved in granuloma formation.

Hyaluronate in bronchoalveolar lavage fluid: a new marker in sarcoidosis reflecting pulmonary disease

Hyaluronate (hyaluronic acid) was not detectable in bronchoalveolar lavage fluid from smoking or nonsmoking healthy volunteers but was present in fluid from 23 patients with sarcoidosis; the mean concentration was 16 micrograms/1 returned fluid (range less than or equal to 5-430) or, expressed in relation to the amount of albumin recovered, 0.22 micrograms/mg albumin (range less than or equal to 0.05-3.6). The serum hyaluronate concentrations in the patients with sarcoidosis were normal. There was a significant inverse correlation between vital lung capacity and hyaluronate concentrations in bronchoalveolar lavage fluid (p less than 0.001), and patients with abnormal lung volumes had hyaluronate concentrations that were on average six times higher than those in patients with normal vital capacity. Duration of disease, pulmonary radiological findings, and markers for macrophage activation (angiotensin converting enzyme) and lymphocyte activation (beta 2 microglobulin) were not correlated with bronchoalveolar lavage fluid hyaluronate. It was concluded that in sarcoidosis release of hyaluronate into the airways is related to lung volume and therefore to the course of the disease. Increased synthesis of hyaluronate in lung parenchyma may reflect activation of fibroblasts, and measurements of hyaluronate may have clinical value for prognosis and treatment.

Neutrophil phagocytosis in sarcoidosis. Reduced C3b receptor-mediated phagocytosis in active and silent sarcoidosis

The phagocytic and complement receptor function of polymorphonuclear neutrophils (PMN) from patients with sarcoidosis was studied using a kinetic assay which allows the distinction to be made between Fc receptor-mediated and C3b receptor-mediated particle uptake. The study included one group (A) of patients with active disease (n = 20), and one group (B) with silent or inactive disease who since 10 years had no symptoms or radiological signs of sarcoidosis (n = 11). Abnormal C3b receptor function was observed in both groups but the impairment was most pronounced in the A group. The presence of C3b receptor dysfunction in both groups with a quantitative difference between the groups, is compatible with C3b receptor dysfunction being a primary causal factor of sarcoidosis.

Serum-mediated stimulation and inhibition of neutrophil locomotion in sarcoidosis

Chemotactic and chemokinetic activity was studied in sera from 57 patients with various stages of sarcoidosis. Reduced chemotactic activity was observed in 39% of the sera, mainly in sera from patients with parenchymal densities on chest radiographs. Increased chemokinetic activity was noted in more than one third of the fresh sarcoid sera. Asymptomatic patients showed higher chemokinetic activity in their sera than patients with symptoms. The presence of heat-stable chemokinetic inhibitors was suggested in one third of the cases. No relationship was found between these inhibitors and the inhibitors of neutrophil phagocytosis previously demonstrated in sarcoid sera. Although many of the findings show minor differences to those of normal sera, the liability in sarcoidosis to produce a variety of inhibitors directed against various functions of neutrophils would theoretically hamper the elimination of putative antigens. The presence of serum mediated stimulation and inhibition of neutrophil locomotion could be significant for the pathogenesis of the disease.

Sarcoidosis: epidemiology and prognosis. A 15-year European study

A 15-year study of patients with sarcoidosis is presented. In most patients, the disease was discovered at a general health screening examination. The mean total incidence among persons 15 yr of age or older was 19 per 100,000 per year (21.7 for women and 16.5 for men). There was a peak incidence in both sexes between the ages of 20 and 34, and in older women, there was a second but lower and broader peak. The frequency of symptoms was greater in older women than in other patients. The accumulated lifetime risk of sarcoidosis was 1.3% for women and almost 1% for men. Patients with Stage I sarcoidosis, i.e., with bilateral hilar adenopathy alone, had the best prognosis, with 50% of the patients showing a normal radiographic picture 15 months after the discovery of the disease. Among patients with Stage II sarcoidosis (both bilateral hilar adenopathy and pulmonary infiltration), it was 36 months before 50% returned to normal radiographically. Resolution of all radiographic evidence of the disease could still occur many years after the first pathologic findings were made on chest films.

Quantitation of immunoglobulin-producing cells in small intestinal mucosa of patients with IgA nephropathy

The numbers and proportions of immunocytes producing IgA, IgM, or IgG were found to be normal in the proximal small intestinal mucosa of patients with IgA nephropathy. There was no indication of any quantitative aberration in the mucosal humoral immune system at this secretory tissue site.

Kinetic studies of phagocytosis. IV. Cellular defects and humoral inhibition as causes of impaired neutrophil phagocytosis in sarcoidosis

Kinetic measurements of the serum-independent uptake of IgG-coated or complement-opsonized latex particles have been performed in 58 patients with sarcoidosis. The mean rate for phagocytic uptake of IgG particles was 0·56 min^-1 which was not different from that of the controls (0·59 min^-1). The phagocytosis of complement-opsonized particles was in the patient group 0·53 min^-1 and significantly (P<0·001) reduced compared to the rate of the controls (mean rate 0·94 min^-1), indicating neutrophil C3b-receptor dysfunction in sarcoidosis. PMNs from patients with sarcoidosis were not stimulated by the presence of autologous serum in contrast to PMNs from normals and in individual cases even a reduced uptake was found. More than one-third of the sarcoid sera also inhibited the phagocytosis of normal PMNs indicating the presence of a phagocytosis-inhibitory activity in sarcoid sera. Patients with more severe lung affection as estimated by measurements of total lung capacity, central airway obstruction, small airway function and pulmonary X-ray changes had a more reduced PMN phagocytosis in the presence of autologous serum than those with minor signs of lung affection (P<0·05). The phagocytosis-inhibitory activity of sarcoid serum was also more pronounced in those individuals who had high pulmonary score (P<0·05) or radiographic stage II-IV sarcoidosis (P<0·01). No correlation was found between serum levels of lactoferrin or lysozyme and any of the phagocytic variables while elevated β₂-microglobulin levels were associated with more pronounced serum-mediated inhibition of PMN phagocytosis (P<0·05). The relevance of these findings to the pathogenesis of granuloma formation in sarcoidosis is discussed.