Asbestos bodies in bronchoalveolar lavage fluid and in lung parenchyma

Numerical concentrations of asbestos bodies (AB) were measured by light microscopy both in samples of bronchoalveolar lavage (BAL) fluid and in samples of lung parenchyma from 69 patients with suspected asbestos-related diseases who had had lavages and later open lung biopsies or autopsies. Objectives were to study the recovery of pulmonary AB by BAL and the ability of BAL concentrations to predict parenchymal concentrations. BAL and parenchymal concentrations were both spread over 6 orders of magnitude and were positively correlated (r = 0.74 between logarithmic values). It is believed that, by a process of progressive elution, AB firmly adherent to the alveolar wall become suspended in BAL fluid; such suspended bodies represent roughly 2% of all the bodies stored in the portion of lung lavaged. Recovery is associated with great interindividual variations. When a measured BAL concentration exceeds 1 AB/ml, it can be quite confidently predicted, however, that the parenchymal concentration is in excess of 1,000 AB/g and that the patient has experienced a nontrivial asbestos exposure.     

Exogenous mineral particles in the human bronchial mucosa and lung parenchyma. I. Nonsmokers in the general population

We extracted mineral particles from 7 different regions of the bronchial tree and 4 regions of lung supplied by these airways from 11 morphologically normal adult autopsy right lungs. All patients were nonsmokers. Particles were identified, counted, and sized by analytical electron microscopy. Both particle concentration and particle size showed a significant negative correlation with airway diameter; detailed analysis showed that the correlation for concentration was only true of large particles. Distance from the carina (pathlength) showed a weaker correlation with particle concentration. The lowest particle concentration was found in the mainstem bronchi, and there was a consistent (case to case) increase in particle concentration with airway generation. Parenchyma supplied by the apical segmental bronchus had a higher particle concentration than that in other sample sites. Segmental bronchial particle size was consistently larger than particle size in the supplied lung tissue, and particles from both upper-lobe tissue sample sites were slightly larger than those from the two lower-lobe sample sites. Bronchial mucosa from all sites showed a predominance of silica, whereas tissue sites appeared to preferentially concentrate silicates, especially kaolin and mica. These observations suggest that in morphologically normal lungs from lifetime nonsmokers (1) in the noncarinal portions of the larger airways, airway diameter and, to a much lesser extent, pathlength are the major influences on long-term bronchial particle concentration and size; (2) tissue particle concentration does not appear to relate to pathlength; (3) the airways accumulate very specific sizes and types of particles compared to the parenchyma, an effect that may influence the location of specific pathologic lesions; and (4) the pattern of long-term particle concentration appears to be fairly similar to acute bronchial deposition patterns seen in experimental human systems, an observation that may imply that long-term burden is the result of translocation of a fraction of the locally deposited particles to the interstitial tissues.     

Comparison between lung parenchyma and bronchoalveolar lavage collagenolytic activity

We have evaluated, in an experimental model of silicosis in guinea pigs, if the presence of collagenolytic activity in bronchoalveolar lavage (BAL) fluid reflects the collagen catabolism in lung parenchyma. We measured simultaneously BAL collagenase activity, using as substrate [³H]type I collagen, and lung collagenolytic activity by the tissue pellet assay. Animals (n = 30) were instilled intratracheally with 50 mg of quartz DQ-12 and sacrificed 15, 30, and 60 days after silica administration. Guinea pigs instilled with saline solution were used as controls. Our results showed that lung parenchymal collagenolytic activity was present in all experimental and normal guinea pigs. There were no statistical differences between silicotic and normal animals at 15 and 30 days. At 60 days, however, a significant decrease in tissue collagenolytic activity was observed in silicotic animals (161 ± 100 vs. 400 ± 152 units of collagenase activity; p < 0.001). In contrast, BAL collagenolytic activity was revealed only in 7 of 10 silicotic animals at 15 days and 30 days, and in 4 of 10 at 60 days. Normal guinea pigs did not exhibit BAL collagenase activity. BAL and tissue collagenase activity from each experimental animal were analyzed by straight line regression and no significant relationship was observed (r = 0.082; p = 0.87). This suggests that BAL collagenolytic activity does not reflect lung tissue collagen turnover. Offprint requests to: M. Selman     

Interstitial lung disease in scleroderma. Immune complexes in sera and bronchoalveolar lavage fluid

Interstitial lung disease is a common feature of scleroderma (systemic sclerosis), and it may be a major determinant of morbidity and mortality. Analysis of bronchoalveolar lavage fluid from patients with scleroderma has shown evidence of inflammation in the lower respiratory tract of many patients. We have analyzed sera and bronchoalveolar lavage fluid from scleroderma patients for the presence of immune complexes, which may play a role in the inflammatory process. Using a solid-phase C1q enzyme-linked immunosorbent assay, we detected immune complexes in the sera of 6 of 23 patients (26%) and in none of 32 controls (P less than 0.01). All 6 patients with serum immune complexes had inflammatory cells in bronchoalveolar lavage fluid, and the presence of serum immune complexes correlated with the percentage of neutrophils in lavage fluid (P less than 0.02). Immune complexes were detected in lavage fluid of 11 of 21 patients (52%) compared with 1 of 7 normal controls (14%). Subjects having immune complexes in lavage fluid had a lower forced vital capacity than did those without lavage fluid immune complexes (P less than 0.05). The levels of immune complexes in bronchoalveolar lavage fluid exceeded those in serum by a mean of 45-fold, suggesting either local formation or selective deposition of immune complexes in the lower respiratory tract of some scleroderma patients.     

Processing of lung lavage fluid causes variability in bronchoalveolar cell count

To study the effects on cell counts of different ways of processing bronchoalveolar lavage (BAL) fluid, we performed 77 BAL in 19 healthy control subjects and in 58 patients with sarcoidosis. We investigated the role of readers, hemocytometers, mode of identification of macrophages, cell washing, and speed of cytocentrifugation. No significant effect of reader or hemocytometer was observed. The percentage of macrophages, determined as large cells stained with neutral red in a Malassez hemocytometer (63.9 +/- 24.6%, mean +/- SD) was lower than the percentage of macrophages determined by May Grunwald Giemsa staining (76.3 +/- 19.2%, p less than 10(-9)). Cell counts decreased 34% after 2 washings (p less than 0.001), and more lymphocytes were counted after cytocentrifugation at 90 g (33.2 +/- 25.3%) than at 23 g (27.7 +/- 22.1%). We conclude that bronchoalveolar cell counts vary with changes in processing lung lavage fluid and that this variability should be considered when using BAL cell counts.     

Vitronectin in bronchoalveolar lavage fluid is increased in patients with interstitial lung disease.

Vitronectin, also known as S-protein, is a 75,000-dalton serum glycoprotein that has a variety of functions, including the capacity to interact with the terminal components of the complement cascade, the coagulation system, and cell surfaces. By virtue of its ability to interact with cells, vitronectin is capable of mediating cell-spreading and adhesion and may also influence cell differentiation and cell growth. To investigate the possibility that vitronectin might contribute to the pathogenesis of interstitial lung disease, vitronectin was measured in bronchoalveolar lavage fluid from patients with sarcoidosis, idiopathic pulmonary fibrosis, and, for comparison, normal volunteers. Vitronectin was detected in lavage fluid and serum of all study subjects. Increased lavage fluid concentrations were found in patients with interstitial lung disease when compared with normal subjects (p less than 0.005), and glucocorticoid-treated patients with interstitial lung disease had lower vitronectin levels than did untreated patients. Furthermore, on SDS-PAGE and Western blot analysis lavage fluid vitronectin comigrated with serum vitronectin, suggesting similar molecular size. Thus, vitronectin is a normal constituent of the epithelial lining fluid, and lavage fluid vitronectin is similar to serum vitronectin. The increase of vitronectin concentrations in the epithelial lining fluid of patients with interstitial lung disease suggests that vitronectin may contribute to the pathogenesis of interstitial lung disease.     

农民肺与支气管肺泡灌洗液中的中性粒细胞相关性的Meta分析

目的从循证医学角度综合分析农民肺疾病进程中的中性粒细胞变化及其与农民肺的相关性。方法采用Rev-Man 5.0分析软件对农民肺病人及模型小鼠支气管肺泡灌洗液（BALF）中的中性粒细胞的数量及百分比的文献进行系统综合定量分析。结果共纳入12个研究,分别对有相同统计内容且可以合并统计的中性粒细胞数量和百分比合并SMD并计算95%C I。依次为中性粒细胞数量：SMD=3.39,95%C I（2.04,4.73）;中性粒细胞百分比：SMD=1.34,95%C I（0.76,1.92）。结论农民肺BALF中的中性粒细胞数量和百分比均明显高于对照组,中性粒细胞与农民肺的疾病进程密切相关。     

Platelet-activating factor in bronchoalveolar lavage fluid from asthmatic subjects

Bronchoalveolar lavage (BAL) was performed on 28 asthma patients, 7 patients with emphysema and 11 control subjects. Total and differential cell counts were performed and cellular metabolic activity was assessed using luminol and lucigenin amplified chemiluminescence. BAL supernatants were assayed for platelet-activating factor (PAF) and lyso-PAF using a sensitive guinea-pig bioassay. Eight of the asthma patients but none of the emphysema patients or control subjects had PAF in their BAL fluid. Lyso-PAF was measurable in BAL fluid in most subjects and no differences were detected between groups. Among the asthma patients, the presence of PAF in BAL supernatant was significantly associated with a combination of low neutrophil and high lymphocyte counts (p less than 0.05) and with macrophage metabolic activity as assessed by lucigenin chemiluminescence (p less than 0.05).     

Increased soluble CD14 in bronchoalveolar lavage fluid of stable lung transplant recipients.

Macrophages, neutrophils and infection have been implicated in the genesis of the bronchiolitis obliterans syndrome (BOS) post lung transplantation. sCD14 is a soluble form of a shed-cell surface protein. It is capable of promoting cytokine-induced inflammation and it's presence in clinically stable lung transplant recipients (LTR) might be important as an early marker of BOS. Bronchalveolar lavage (BAL) and blood samples were taken from 26 stable LTR, at or near their best forced expiratory volume in one second who were free from infection. sCD14 levels were measured via enzyme-linked immunosorbent assay. Cell counts were performed on unfiltered BAL. LTR neutrophil count, BAL sCD14 and serum sCD14 levels were higher than controls (median 3.8% versus 1.3%, p<0.05; 11.5 ng x mL(-1) versus 6 ng x mL(-1), p<0.001; 6.2 microg x mL(-1) versus 2.4 microg x mL(-1), p<0.05, respectively). BAL albumin and sCD14 correlated (regression coefficient: 0.77, p<0.001). In this hypothesis-generating, cross-sectional study, the authors have described for the first time soluble CD14 levels in the bronchoalveolar lavage and serum of stable lung transplant recipients, and show that these are elevated compared to controls. This is a practicable candidate marker system, which can be tested for a predictive role in bronchiolitis obliterans syndrome following lung transplantation. The origin of this cellular protein and its temporal relationship to the development of the bronchiolitis obliterans syndrome remains to be elucidated in more definitive longitudinal studies, which should include other measurements potentially relevant to the innate immune system, such as bronchoalveolar lavage endotoxin levels.     

Antibacterial components in bronchoalveolar lavage fluid from healthy individuals and sarcoidosis patients.

Antibacterial peptides and proteins are an integral part of the epithelial defense barrier that provides immediate protection against bacterial invasion. In humans, alpha-defensins are mainly bactericidal effectors in circulating granulocytes, beta-defensin-1 is synthesized in epithelial cells, and LL-37 is produced in granulocytes but is also induced in skin epithelia during inflammation. To investigate the importance of these defense effectors in disease, we analyzed bronchoalveolar lavage fluid (BALF) for bactericidal activity. Antibacterial activity was found in BALF material from healthy individuals and sarcoidosis patients, with enhanced activity in BALF from the patients. The activity was present as several antibacterial components, of which we have so far characterized LL-37, lysozyme, alpha-defensins, and antileukoprotease. In addition, the antibacterial peptide LL-37 was located in alveolar macrophages, bronchial epithelial cells, and bronchial glands, suggesting that it has a defensive role in airway mucosa. In conclusion, the airway epithelium is protected by a complex antibacterial defense system. This is activated in sarcoidosis, and may explain why these patients seldom develop severe respiratory tract infections.     

Interlobar differences in bronchoalveolar lavage fluid from children with cystic fibrosis.

Bronchoalveolar lavage (BAL) performed in specialist centres has improved the understanding of infant cystic fibrosis (CF) lung disease. As most researchers sample from a single lobe, it was determined whether BAL results could be generalized to other lung segments. Thirty-three CF children, aged 1.5-57 months, underwent in random order sequential BAL of their right middle and lingula lobes. Specimens from each lobe had separate quantitative bacteriology, cytology and cytokine analysis. Bacterial counts > or = 1 x 10(5) colony forming units (cfu) x mL(-1) were observed in nine (27%) subjects, including six involving only the right middle lobe. These six children had similar inflammatory indices in their right middle and lingula lobes, and interleukin (IL)-8 concentrations in the latter were significantly higher than that observed within the lingula lobes of the 24 CF children with bacterial counts < 1 x 10(5) cfu x mL(-1). Lingula neutrophil and IL-8 levels correlated best with right middle lobe bacteria numbers. This observational study in cystic fibrosis children suggests that while inflammation is detected in both lungs, bacterial distribution may be more inhomogeneous. Bronchoalveolar lavage microbiological findings from a single lobe may therefore, not be generalized to other lung segments. When performing bronchoalveolar lavage in cystic fibrosis children, it is important to sample from multiple sites.     

Fractional processing of sequential bronchoalveolar lavage fluid from intubated babies.

Two groups of intubated newborn babies were studied to determine the clinical effects of interrupted bronchoalveolar lavage (BAL) by suction catheter (S-BAL) and the similarities to adult fibreoptic BAL of fractional processing of sequential lavage fluid (BALF). Both groups were lavaged by two aliquots of 1 ml.kg-1, instilled via a blindly placed suction catheter, wedged on two separate insertions through the right main bronchus. In 14 infants, (sequential lavage group), BALF aliquots were analysed separately. There were no differences in the volumes recovered or total cell counts between the first and second BALF aliquots. Where cell morphology was visible (n = 11), the percentage of macrophages, but not the absolute number, increased in the second BALF aliquot (p less than 0.01). BALF urea and epithelial lining fluid volume estimated by urea dilution were similar between the two aliquots (n = 8). In a separate group (blood gas group), vital signs were recorded in 10 infants undergoing S-BAL. At 1 min after lavage there was a rise in mean arterial blood pressure (39 vs 49.5 mmHg, p less than 0.05) and a fall in transcutaneous oxygenation (10.6 vs 7.5 kPa, p less than 0.05). Recovery was present at 3 min post-S-BAL, but mean blood pressure remained elevated (39 vs 45 mmHg, p less than 0.05) and transcutaneous oxygen continued to be lower when compared to baseline values (10.6 vs 9.2 kPa, p less than 0.05). S-BAL of intubated infants appears to sample both the proximal and distal airways and results in changes in vital signs similar to routine non-selective endotracheal suctioning.     

Interleukin 5 and granulocyte-macrophage colony-stimulating factor levels in bronchoalveolar lavage fluid in interstitial lung disease.

The purpose of this study was to evaluate the role of several eosinophil growth factors including interleukin (IL)-5, interleukin (IL)-3 and granulocyte-macrophage colony-stimulating factor (GM-CSF) in the pathogenesis of interstitial lung disease with eosinophilia. IL-5, IL-3 and GM-CSF in bronchoalveolar lavage fluid (BALF) were measured by enzyme-linked immunosorbent assay (ELISA) in patients with eosinophilic pneumonia (EP), bronchiolitis obliterans organizing pneumonia (BOOP), idiopathic pulmonary fibrosis (IPF), sarcoidosis and healthy volunteers. IL-5 in BALF was high only in patients with EP. IL-3 in BALF was undetectable in the majority of patients with these diseases. GM-CSF in BALF was detectable in 30-67% of each group of patients. In patients with BOOP and IPF, the number of eosinophils in BALF was higher in patients with detectable GM-CSF than in patients in whom GM-CSF was below the detection limit. Eosinophil cationic protein (ECP) was detected in all patients with EP and some with BOOP and IPF. There was a significant correlation between ECP levels and percentage or number of eosinophils in BALF. The results suggest the possibility that interleukin 5 in eosinophilic pneumonia, and granulocyte-macrophage colony-stimulating factor in bronchiolitis obliterans organizing pneumonia and idiopathic pulmonary fibrosis may play important roles in eosinophil recruitment in the lung. Activation of eosinophils in the lung is likely to be induced by both interleukin 5 and granulocyte-macrophage colony-stimulating factor.     

Mast cells in bronchoalveolar lavage fluid of patients with interstitial lung diseases

Mast cells play an important role in tissue inflammation, fibrosis and remodelling. They are found in bronchoalveolar lavage fluid (BAL) of healthy persons only in small numbers. We investigated the number of mast cells in interstitial lung diseases and analysed our data for correlations with clinical parameters, cellular and non-cellular parameters of BAL. We found following counts of mast cells in % of total BAL cells: Sarcoidosis (n = 123); 0.22 +/- 0,04 %, idiopathic pulmonary fibrosis (IPF) (n = 35); 0.39 +/- 0.47 %, cryptogenic organising pneumonia (COP) (n = 27); 2.05 +/- 2.19 %, hypersensitivity pneumonitis (HP) (n = 24); 1.02 +/- 1.05 %, rheumatoid lung (n = 20); 0.21 +/- 0.21 %, respiratory bronchiolitis-associated interstitial lung disease (RBILD) (n = 11); 0.16 +/- 0.29 %) and control group (n = 16); 0.06 +/- 0.16 %. Compared to controls mast cells were increased in COP (p < 0.001) and HP (p < 0,01). Correlation analysis showed that an increased mast cell count correlated with: Higher age (sarcoidosis (p = 0.03); smaller vital capacity (sarcoidosis (p = 0.01)), smaller FEV 1 (sarcoidosis (p = 0.04), RBILD (p = 0.04)); higher alkaline phosphatase in BAL (sarcoidosis (p = 0.004), HP (p = 0.02), COP (p = 0.04); higher albumin level in BAL (sarcoidosis (p = 0.000), IPF (p = 0.003); higher cell counts in BAL (sarcoidosis (p = 0.013), COP (p = 0.04)); lower portion of macrophages in BAL cells (sarcoidosis (p = 0.001), HP (p = 0.02), COP (p = 0.02)); higher portion of lymphocytes in BAL cells (sarcoidosis (p = 0.03)); higher portion of neutrophils in BAL cells (sarcoidosis (p = 0.007)); higher portion of eosinophils in BAL cells (sarcoidosis (p = 0.001), HP (p = 0.006)). Correlations to smoking history in pack years and to lymphocyte surface markers CD3, CD4, CD8 were not found. In conclusion comparing different interstitial lung diseases we found significantly increased mast cell counts in COP and HP. Moreover there were correlations of increased mast cell counts with more intensive alveolitis and exudation.     

Low neutral endopeptidase levels in bronchoalveolar lavage fluid of lung cancer patients

Neutral endopeptidase (NEP) is a cell surface enzyme found in normal human lung and which hydrolyzes small bioactive peptides, some of which act as growth factors for normal and malignant airway epithelial cells. Expression of NEP varies widely in human lung tissue from different individuals. NEP is often expressed at low or undetectable levels in both small-cell and non-small-cell lung cancer, and inhibits the growth of lung cancer cell lines. Variation in the expression of NEP could be a factor in susceptibility to lung cancer. We hypothesized that NEP could be measured in bronchoalveolar lavage fluid (BALF) and that airway levels of NEP would be low in lung cancer patients as compared with normal controls. We measured NEP and total protein in cell-free BALF supernatant, and expressed the respective concentrations as a ratio. NEP levels showed wide variation in BALF of healthy volunteers. Most patients with lung cancer had no NEP detectable in BALF. The mean NEP/total protein ratio was significantly lower in patients with lung cancer (0.87 +/- 0.7 ng NEP/mg protein) than in normal healthy subjects (14.0 +/- 4.3, p < 0.0003). We conclude that NEP levels are highly variable in BALF of normal volunteers, and are low or undetectable in most BALF specimens from patients with lung cancer. Low NEP levels in the airways may be a factor in the pathogenesis of carcinoma of the lung.     

Proangiogenic activity in bronchoalveolar lavage fluid from patients with asthma

RATIONALE: Asthmatic airways have an increased number and size of vascular structures, which contribute to airflow obstruction and hyperresponsiveness. OBJECTIVES: We examined whether proangiogenic mediators are elevated in bronchoalveolar lavage fluid (BALF) from subjects with asthma and if this translated to induction of angiogenesis. METHODS: Angiogenic activity in BALF from 12 healthy, nonatopic subjects and 10 atopic subjects with mild asthma was evaluated by examining tubule formation at 11 days in cocultures of human endothelial cells with dermal fibroblasts. Vascular structures were visualized by anti-CD31 labeling and quantified by image analysis. Angiogenic growth factors in BALF from healthy subjects and subjects with asthma were identified using antibody arrays and by ELISA. MEASUREMENTS AND MAIN RESULTS: Angiogenic activity induced by BALF from healthy subjects was not different from basal tubule formation (p>0.05). However, induction of tubular structures by asthmatic BALF was 2.5-fold greater (p<0.001) compared with healthy samples. Similarly, levels of proangiogenic growth factors (angiogenin, vascular endothelial growth factor [VEGF], monocyte chemotactic protein-1) were increased approximately 2.5-fold (p<0.05) in BALF from subjects with asthma, whereas antiangiogenic factors (endostatin, Ang-2) were unchanged. A blocking anti-VEGF antibody abolished tubule formation induced by BALF from either healthy subjects or subjects with asthma (p<0.01). Immunodepletion of VEGF had no effect on basal tubule formation induced by healthy BALF but abrogated enhanced tubule formation by asthmatic BALF (p<0.01). CONCLUSIONS: BALF collected from subjects with asthma but not healthy subjects is functionally active in promoting angiogenesis in vitro. The proangiogenic capacity of BALF from subjects with asthma resides in elevated VEGF derived from asthmatic airways. This observation supports VEGF as a key factor in vascular remodeling in asthma.     

Role of bronchoalveolar lavage in interstitial lung disease.

Bronchoalveolar lavage remains an important research tool in understanding ILD. It is still an important part of the clinical management of patients with ILD. It is most useful in detecting unusual forms of ILD. It helps the clinician narrow down the possible causes of the interstitial pattern. It also can confirm a clinical impression of certain conditions. Although rarely diagnostic, it is often supportive. In conjunction with high-resolution CT scan, most patients with ILD can be diagnosed using relatively noninvasive methods.     

Cotinine levels in serum and bronchoalveolar lavage fluid

Cotinine is a major metabolite of nicotine. This study was planned to investigate the relationship between bronchoalveolar lavage (BAL) fluid cotinine levels and serum cotinine levels in smokers and nonsmokers with various pulmonary diseases and to investigate whether these levels are affected by passive smoking. Serum and BAL fluid cotinine levels were measured in 27 patients. BAL cotinine levels were measured using a sensitive ELISA kit produced to measure cotinine in saliva. Plates were read by microuant (BioTek, USA) micro plate reader. All patient serum cotinine levels were detectable except for one nonsmoker patient. However, BAL fluid cotinine levels were measurable in only 6 patients (two of them were nonsmokers). A significant positive correlation was seen between serum and BAL fluid cotinine levels (r = 0.726; p = 0.000). Serum cotinine levels were significantly higher in present smokers than non-smokers (21.0 +/- 16.01; 5.35 +/- 7.65; p = 0.004). However, there were no significant differences in BAL fluid cotinine levels between smokers and nonsmokers. Passive smoking can increase nicotine metabolites in serum and other body fluids, including BAL fluid. Since BAL fluid and serum cotinine levels were well correlated, there is no need to use invasive procedures, such as bronchoscopy and expensive, time consuming BAL fluid analyses. Serum cotinine levels can give a rough idea of smoking status. BAL fluid cotinine meaurements should be done for only scientific reasons.