SELDI-TOF derived serum biomarkers failed to differentiate between patients with beryllium sensitisation and patients with chronic beryllium disease.

BACKGROUND: People exposed to beryllium may develop beryllium sensitisation (BeS) and, in some cases, progress to chronic beryllium disease (CBD). OBJECTIVES: The objective of this study was to test the ability of proteomic technology to identify patterns of serum protein biomarkers that allow differentiation between BeS and CBD and thus remove the need for invasive bronchoscopic procedures. METHODS: Initially, SELDI-TOF methodology and analysis was performed on serum samples from 30 CBD and 31 BeS patients. RESULTS: This 'starter set' yielded two distinct biomarker pattern sets with eight candidate proteins. The first set differentiated between BeS and CBD with 83.3% sensitivity and 82.3% specificity, with 10-fold cross-validation of 75% and 79%, respectively. The second set of biomarkers yielded higher sensitivity (90.0%) and higher specificity (90.3%), with 10-fold cross-validation of 71.7% and 82.3%, respectively. Due to its greater sensitivity and specificity, the second set of biomarkers was used as the framework for differentiating between CBD and BeS in a second set of serum samples from 450 patients with BeS and CBD. When this larger set of samples was subjected to the biomarker framework in a blinded fashion, it yielded a sensitivity of 43.53% and a specificity of 38.93%. CONCLUSIONS: Due to these low sensitivity and specificity values, we have concluded that, currently, the unique set of SELDI-TOF derived biomarkers does not possess the qualities that would allow it to differentiate between a CBD patient and a BeS patient using serum protein biomarkers. Future refinements in sample collection or proteomic technology may be needed to improve biomarker discovery.

CC chemokine receptor 5 gene polymorphisms in beryllium disease.

CC chemokine receptor 5 (CCR5) is expressed on type-1 T-helper cells, which are involved in the pathogenesis of the granulomatous lung disease chronic beryllium disease (CBD). CCR5 gene (CCR5) polymorphisms are associated with sarcoidosis severity. The present study explores associations between CCR5 polymorphisms and CBD and its disease progression. Eight CCR5 polymorphisms were genotyped in CBD (n = 88), beryllium sensitisation (BeS; n = 86) and beryllium-exposed nondiseased controls (n = 173) using PCR with sequence-specific primers. Pulmonary function and bronchoalveolar lavage data were examined for associations with genotypes. There were no significant differences in genotype and allele frequency between CBD, BeS individuals and controls. In CBD, associations were found with decline in forced expiratory volume in 1 s and forced vital capacity and the CCR5 -3458 thymidine (T)T genotype (p<0.0001), and an increase in alveolar-arterial oxygen tension difference at rest (p = 0.003) and at maximum exercise (p = 0.01) and the -5663 adenine allele. Increased bronchoalveolar lavage lymphocyte numbers were associated with CCR5 -2459 guanine/-2135T (p = 0.01) only in the combined CBD and BeS group. This is the first study showing that CCR5 polymorphisms are associated with worsening pulmonary function over time in CBD, suggesting that CCR5 is important in the progression of pulmonary function in CBD. Further studies would be useful to clarify the mechanism whereby CCR5 polymorphisms affect progression of CBD.

A novel adaptor-related protein complex.

Coat proteins are required for the budding of the transport vesicles that mediate membrane traffic pathways, but for many pathways such proteins pathways, but for many pathways such proteins have not yet been identified. We have raised antibodies against p47, a homologue of the medium chains of the adaptor complexes of clathrin-coated vesicles (Pevsner, J., W. Volknandt, B.R. Wong, and R.H. Scheller. 1994. Gene (Amst.). 146:279-283), to determine whether this protein might be a component of a new type of coat. p47 coimmunoprecipitates with three other proteins: two unknown proteins of 160 and 25 kD, and beta-NAP, a homologue of the beta/beta'-adaptins, indicating that it is a subunit of an adaptor-like heterotetrameric complex. However, p47 is not enriched in preparations of clathrin-coated vesicles. Recruitment of the p47-containing complex onto cell membranes is stimulated by GTP gamma S and blocked by brefeldin A, indicating that, like other coat proteins, its membrane association is regulated by an ARF. The newly recruited complex is localized to non-clathrin-coated buds and vesicles associated with the TGN. Endogenous complex in primary cultures of neuronal cells is also localized to the TGN, and in addition, some complex is associated with the plasma membrane. These results indicate that the complex is a component of a novel type of coat that facilitates the budding of vesicles from the TGN, possibly for transporting newly synthesized proteins to the plasma membrane.

Increased levels of nerve growth factor in the airways of patients with sarcoidosis.

OBJECTIVES: Nerve growth factor (NGF) is a potent neuronal growth factor with inflammatory properties that recently has been proposed to be of importance in airway pathology. A role for NGF in the inflammatory granulomatous lung disease sarcoidosis is not well elucidated. The aims of this study were to investigate the secreted levels of NGF in bronchoalveolar lavage fluid (BALF) from sarcoidosis patients compared with patients with resolved disease, patients with another granulomatous disease--chronic beryllium disease (CBD)--and healthy subjects and also to investigate the relationship between NGF levels and markers of inflammation. METHODS AND RESULTS: NGF levels in BALF from 56 patients with active sarcoidosis (22 with Löfgren's syndrome), nine subjects with resolved sarcoidosis, six patients with CBD, and 31 healthy subjects were compared. A 10-fold elevation of NGF levels was found in patients with active sarcoidosis compared with subjects with clinically resolved sarcoidosis, patients with CBD and healthy subjects. In sarcoidosis patients, positive correlations between concentrations of NGF and lymphocytes, eosinophils and interferon-gamma, interleukin (IL)-4, IL-10, IL-12 were found. CONCLUSIONS: We demonstrate that secreted levels of NGF are markedly enhanced in the airways in active pulmonary sarcoidosis. Furthermore, a relationship between NGF and pulmonary inflammation in sarcoidosis is supported.

HLA and environmental interactions in sarcoidosis.

Sarcoidosis is a systemic granulomatosis of unknown etiology despite being described over 100 years ago. While both genetic predisposition and environmental exposures have been proposed as playing a role in this disease, there have not been any systematic investigations of gene-environmental interaction in this disease. In the ACCESS dataset, detailed environmental histories and high resolution HLA class II typing were performed on 476 cases of newly diagnosed sarcoidosis and 476 matched controls from the patients' community. We evaluated gene-environmental interactions in exposures or HLA class II alleles that were present in > 5% of the population and had an odd ratio of > 1.0. Four exposures and four HLA Class II alleles met these criteria and were evaluated. Significant interaction was observed between HLA DRB1*1101 and insecticide exposure at work (p < 0.10) and suggestive interaction was observed between HLA DRB1*1101 and exposure to mold and musty odors and DRB1*1501 and insecticide exposure at work (P < 0.15). In addition, HLA DRB1*1101 and insecticide exposure at work was associated with extrapulmonary sarcoidosis, specifically cardiac sarcoidosis and hypercalcemia (p<0.05) and HLA DRB1*1101 and exposure to molds and musty odors was associated with pulmonary only sarcoidosis (P < 0.05). These studies suggest that sarcoidosis is due to an interaction of genetic predisposition and environmental exposure in at least some cases of sarcoidosis. Future studies in defined phenotypes of sarcoidosis may be necessary to define environmental and genetic associations with sarcoidosis.

Clonal expansion of lung V delta 1+ T cells in pulmonary sarcoidosis.

Sarcoidosis is a multisystem disease of unknown etiology characterized by the presence of noncaseating granulomas in involved tissues. To investigate a potential role for gamma/delta T cells in the pathogenesis of pulmonary sarcoidosis, we studied lung and blood T cells from patients for preferential expression of particular gamma/delta T cell receptors. An abnormally high percentage of gamma/delta cells was found in the blood of some patients. However, the increased percentage did not reflect an increase in absolute number, and appeared to be secondary to a decrease in T cells expressing alpha/beta receptors. Furthermore, as in normals, the circulating gamma/delta cells in patients predominantly expressed V gamma 9/V delta 2 receptors, a subset that was not enriched at the site of disease. In contrast, in the lung, an increased percentage of gamma/delta cells expressing V delta 1 was found in a subset of patients. Importantly, these cells demonstrated evidence of prior activation by selectively expanding in vitro in the presence of interleukin 2. Furthermore, an analysis of junctional region sequences revealed their clonal nature. These clonal expansions of V delta 1+ cells in pulmonary sarcoidosis provide evidence for a disease process that involves specific recognition of a local antigen by T cells, and contributes new information regarding the nature of the as yet undefined antigenic stimulus.

Significance of the blood beryllium lymphocyte proliferation test.

The blood beryllium lymphocyte proliferation test (BeLPT) is an in vitro measure of the beryllium antigen-specific cell-mediated immune response. This response to beryllium is now understood to play a central role in the immunopathogenesis of chronic beryllium disease (CBD). Although there remain some unresolved methodologic issues with testing, the blood BeLPT has already undergone sufficient development and field assessment to lead to a number of important conclusions: a) The BeLPT identifies beryllium sensitization and CBD earlier and better than any other clinical test presently available. b) The CBD cases identified with the blood test are clinically significant. c) A subset of the people identified by the BeLPT who do not yet have clinical disease will progress and require treatment with corticosteroids for impairing illness. d) The BeLPT can be used to improve clinical diagnostic accuracy and to correct mistaken diagnoses. e) The blood test can be used in screening large numbers of exposed workers because it is sensitive and specific and has high positive and negative predictive value for CBD. f) In every workforce studied to date, the BeLPT has identified beryllium sensitization and CBD that had been missed by conventional screening efforts. g) Worker populations that have been characterized using the BeLPT can help to elucidate the role of exposure genetics and dysregulated inflammation in the genesis of occupational lung disease.

The natural history of beryllium sensitization and chronic beryllium disease.

With the advent of in vitro immunologic testing, we can now detect exposed individuals who are sensitized to beryllium and those who have chronic beryllium disease (CBD) with lung pathology and impairment. Earlier detection and more accurate diagnostic tools raise new questions about the natural history of sensitization and granulomatous disease. Preliminary data suggest that early detection identifies people who are sensitized to beryllium and that these individuals are at risk for progressing into clinical disease. This article discusses the historical, recent, and ongoing studies germane to our understanding of CBD natural history, including the immunologic and inflammatory basis of the disease, the environmental and host risk factors for disease progression, biological markers of disease severity and activity that may help predict outcome, and the implications for broad-based workplace screening to identify patients at the earliest stages of beryllium sensitization and disease.

Inorganic dust pneumonias: the metal-related parenchymal disorders.

In recent years the greatest progress in our understanding of pneumoconioses, other than those produced by asbestos, silica, and coal, has been in the arena of metal-induced parenchymal lung disorders. Inhalation of metal dusts and fumes can induce a wide range of lung pathology, including airways disorders, cancer, and parenchymal diseases. The emphasis of this update is on parenchymal diseases caused by metal inhalation, including granulomatous disease, giant cell interstitial pneumonitis, chemical pneumonitis, and interstitial fibrosis, among others. The clinical characteristics, epidemiology, and pathogenesis of disorders arising from exposure to aluminum, beryllium, cadmium, cobalt, copper, iron, mercury, and nickel are presented in detail. Metal fume fever, an inhalation fever syndrome attributed to exposure to a number of metals, is also discussed. Advances in our knowledge of antigen-specific immunologic reactions in the lung are particularly evident in disorders secondary to beryllium and nickel exposure, where immunologic mechanisms have been well characterized. For example, current evidence suggests that beryllium acts as an antigen, or hapten, and is presented by antigen-presenting cells to CD4+ T cells, which possess specific surface antigen receptors. Other metals such as cadmium and mercury induce nonspecific damage, probably by initiating production of reactive oxygen species. Additionally, genetic susceptibility markers associated with increased risk have been identified in some metal-related diseases such as chronic beryllium disease and hard metal disease. Future research needs include development of biologic markers of metal-induced immunologic disease, detailed characterization of human exposure, examination of gene alleles that might confer risk, and association of exposure data with that of genetic susceptibility.

Cytokine production by bronchoalveolar lavage cells in chronic beryllium disease.

Chronic beryllium disease (CBD) begins as a sensitizing cell-mediated immune response to beryllium antigen that progresses to granulomatous lung disease. Previous studies demonstrated the involvement of proinflammatory cytokines in the disease process, but the pattern and regulation of cytokine release is unknown. Using bronchoalveolar lavage (BAL) cells from CBD patients in short-term tissue culture, we evaluated cytokine protein levels by enzyme-linked immunosorbent assay and T-lymphocyte proliferation by tritiated thymidine incorporation. We observed the beryllium-stimulated release of tumor necrosis factor-alpha (TNF-alpha), interleukin-6 (IL-6), interleukin-2 (IL-2), and interferon-gamma (IFN-gamma) but not interleukin-4 (IL-4). Beryllium-stimulated IFN-gamma release was sustained to 168 hr in culture, whereas IL-2 concentrations returned to baseline after 24 hr. Neutralization of IL-2 decreased beryllium-stimulated T-lymphocyte proliferation, but the level of proliferation remained elevated in comparison to unstimulated BAL cells. These data suggest that T helper 1 (Th1) lymphocytes participate in the beryllium disease process; that IFN-gamma levels remain elevated after IL-2 levels return to baseline; and that IL-2 participates directly in beryllium-stimulated T-cell proliferation, but other T-lymphocyte mitogenic cytokines may be involved.

Quantitative computed tomography detects air trapping due to asthma.

OBJECTIVE: The purpose of this study was to prospectively see if quantitative computed tomography (QCT) could separate asthmatic patients from normal control subjects. The QCT results were also correlated with the pulmonary function tests (PFT) that were done on both the asthmatic patients and control subjects. SUBJECTS AND METHODS: Eighteen adult nonsmoking asthmatics and 22 adult control subjects were entered into the study. Quantitative CT was performed at the level of the transverse aorta and just above the diaphragm at both end inspiration and end expiration in all patients and control subjects: 10-mm and 1.5-mm collimation using a high spatial frequency algorithm was used to obtain the QCT examinations. The percent of pixels below -900 Hounsfeld units, pixel index, in each of the QCT axial images of the lungs was calculated for each asthmatic and control subject in the study. Pulmonary function testing was performed on both the asthmatics and control subjects and included determination of FEV1, FVC, FRC, RV, and TLC. Unpaired Student's t test analysis of the QCT data was done to statistically compare the asthmatics with the control subjects. Linear regression analysis was done to compare the QCT results with PFT data on the asthmatics and control subjects. RESULTS: When scans were performed at end expiration, at a level immediately superior to the diaphragm, the mean pixel index was significantly higher in asthmatic subjects compared with normal individuals on both CT (mean for normal subjects 0.16 vs 4.45 for asthmatics, p < 0.004) and high-resolution CT (HRCT) images (mean for normal subjects 1.04 vs 10.03 in asthmatics, p < 0.0001) indicating more areas of low attenuation in asthmatics. The CT and HRCT images from the lower lung zones that were performed at end expiration provided the best separation between the groups. The pixel index on expiration correlated with the degree of air trapping and airflow limitation in the asthmatic group based on FEV1, FRC, RV, and to a lesser extent, FVC. CONCLUSION: Expiratory QCT is a useful method to assess air trapping in asthmatic patients. The percent of abnormal lung in asthmatics as determined by QCT has a significant correlation with the PFTs that reflect air trapping in asthmatic patients. Quantitative CT may be helpful in assessing degrees of air trapping present in other diseases affecting the airways.

Indirect and direct gas exchange at maximum exercise in beryllium sensitization and disease.

STUDY OBJECTIVES: To determine whether pulse oximetry accurately estimates arterial blood gas measurements during exercise in the assessment of chronic beryllium disease (CBD) and beryllium sensitization (BeS). DESIGN: Participants underwent maximal exercise physiology testing in a clinical-practice setting. Oxygen saturation in the blood was measured through an indwelling arterial line and by pulse oximetry. SETTING: All exercise physiology tests were performed in the pulmonary physiology unit of the National Jewish Medical and Research Center (NJMRC) between December 1985 and November 1998. PATIENTS: We analyzed the exercise physiology data for 168 individuals who were referred to NJMRC for evaluation of possible CBD and underwent exercise testing. On evaluation, they subsequently received diagnoses of either CBD or BeS. RESULTS: In BeS subjects, the percentage of oxygen saturation as measured by pulse oximetry (SpO(2)) often underestimated the percentage of arterial oxygen saturation (SaO(2)) (mean [+/- SD] underestimation, 0.88 +/- 4.6%) at maximum exercise and showed no significant correlation (r = -0.13; p = 0.3). The use of SpO(2) misclassified 14.9% of BeS subjects as having abnormal gas exchange levels (< 90%) that were normal by arterial blood gas measurement. In contrast, SpO(2) and SaO(2) values correlated at maximum exercise in CBD subjects (r = 0.55 [corrected]; p = 0.0001) without exhibiting SpO(2) underestimation of SaO(2), and misclassification occurred in only 5.9%. CONCLUSIONS: These data suggest that pulse oximetry cannot be used reliably to distinguish between CBD and BeS and, thus, is not an adequate substitute for arterial blood gas analysis with exercise.

Suppurative mediastinitis after open heart surgery. A case control study of risk factors.

Suppurative mediastinitis occurred in 68 of 9,965 patients (0.7 percent) who underwent median sternotomy at Emory University Hospital from 1973 through 1982. Case-control methodology was used to identify preoperative, intraoperative, and postoperative risk factors for the development of poststernotomy mediastinitis. The following 12 individually significant risk factors were identified by univariate analysis: preoperative factors: history of chronic obstructive pulmonary disease (COPD), history of prior sternotomy, pyuria, low ejection fraction, and high left ventricular end-diastolic pressure; intraoperative factors: valvular or aortic aneurysm surgery, prolonged bypass pump time, repeat placement on bypass, duration of surgery; and postoperative factors: surgical reexploration due to postoperative hemorrhage, cardiopulmonary resuscitation in the immediate postoperative period, prolonged time (greater than 48 hours) on mechanical ventilation. By logistic regression analysis, three of these factors were found to be associated independently with increased odds of developing mediastinitis: duration of surgery, history of COPD, and prolonged postoperative mechanical ventilation.

Recent findings on preventable hospitalizations.

Disparities in health outcomes for low-income populations as documented by rates of preventable hospital admission remains large in the United States, even with the moderate expansion of Medicaid and efforts at the state and local levels to improve primary care services that began in the mid-1980s. These differences in outcome for rich and poor are not an isolated phenomenon of a few old and decaying Northeast urban centers but are documented in a broad range of urban areas. Much smaller differences are found in urban areas in Ontario, where universal coverage may help to reduce barriers to care.

Occupational asthma. Diagnosis, management, and prevention.

Occupational asthma is the most common work-related respiratory disorder but frequently goes undetected, leading to poorer clinical outcomes for asthmatic patients. Inhalational exposures to both allergens and irritants in the workplace cause asthma. The likelihood of recovery hinges on early recognition and avoidance of further exposure. This article outlines the clinical approach to the detection, management, and prevention of occupational asthma, emphasizing recent advances and practical advice on how to investigate the causes of reactive airway disease.

Bronchoalveolar lavage macrophage-lymphocyte clusters in granulomatous disease are linked to lymphocytosis.

BACKGROUND AND AIM OF THE WORK: Clusters of macrophages associated with lymphocytes (ML clusters) have been observed among the bronchoalveolar lavage (BAL) cells of patients with pulmonary disease. We tested the hypothesis that ML clusters might be found among the BAL cells from patients with granulomatous disease. METHODS: We measured the number of ML clusters among the BAL cells from normal controls (n = 13), sarcoidosis patients (n = 18), beryllium-sensitized (BeS) patients (n = 21) and chronic beryllium disease (CBD) patients (n = 15). RESULTS: ML clusters were observed in the BAL cells of all groups, but at different frequencies: normal 8.5% (median, range 2-15%); BeS 7% (range 2-31%); sarcoidosis 14% (range 4-50%); and CBD 17% (range 6-73%). This data suggested that ML clusters were increased in granulomatous lung disease. However, the percentage of ML clusters strongly correlated with the BAL lymphocyte percentage (rho = 0.79). Cohort analysis showed that increases in macrophages having 2, 3 or > 3 associated lymphocytes correlated with an increase in lymphocyte percentage. CONCLUSIONS: An increase in ML clusters in BAL cells is not specific for granulomatous disease and is associated with the increase in BAL lymphocytes.

Beryllium-stimulation does not activate transcription factors in a mouse hybrid macrophage cell line.

We tested the hypothesis that beryllium (Be) could stimulate H36.12j cell (12j) TNF-alpha production by transcription factor-mediated pathways similar to those induced by either LPS- or IFN-gamma stimulation. Unstimulated 12j cells produce constitutive levels of TNF-alpha (175+/-18 pg/ml, mean +/- SEM) detected by ELISA of culture supernatants after 24 h. Beryllium-stimulated (100 microM BeSO4) 12j cell TNF-alpha (724+/-47 pg/ml) was observed after 24 h while LPS-stimulated (1 microg/ml) TNF-alpha (515+/-151 pg/ml) after 6 h. Recombinant-Mu-IFN-gamma (10 U) stimulated 12j cell TNF-alpha at lower levels (284+/-31 pg/ml) while rMu-IFN-gamma + Be-stimulated 12j cells produced 1195+/-225 pg/ml TNF-alpha. Constitutive levels of transcription factors were observed in unstimulated 12j cell nuclei. In LPS-stimulated 12j cells IkappaBalpha was degraded in the cytoplasm and increased levels of NF-kappaB were found in nuclei after 30 min. After 3 h there were increased levels of AP-1 and CREB, with increased amounts of Fos family, Jun B and Jun D transcription factors. In contrast, Be-stimulation failed to increase the levels of any transcription factor tested, NF-kappaB, AP-1, AP-2, CREB, C/EBP, Sp-1, Egr-1, Ets, NF-Y or Oct-1, in 12j cells. A pattern of increased transcription factors, similar to that observed for LPS-stimulation, was found in 12j cell nuclei after stimulation with rMu-IFN-gamma. However, NF-kappaB was increased at 3 h while AP-1 (Jun B and Jun D) and CREB were increased at 15 h. Co-stimulation of 12j cells with rMu-IFN-gamma + Be increased the levels of NF-KB in 12j cell nuclei at 3 h, and the levels of AP-1 and CREB at 15 h, however, only Jun B was increased. Our data show 12j cell TNF-alpha production was associated with increased levels of transcription factors present in nuclei with disparate kinetics and patterns of expression depending on the trigger. We reject our initial hypothesis and conclude that Be-stimulation signals 12j cell TNF-alpha synthesis via a transcription factor-independent pathway. Beryllium may induce novel pathways of macrophage cytokine gene regulation.

Beryllium-stimulated production of tumor necrosis factor-alpha by a mouse hybrid macrophage cell line.

Chronic beryllium disease (CBD) results from exposure to the light-weight metal beryllium (Be). In vitro stimulation of bronchoalveolar lavage cells from CBD subjects causes the production of high levels of TNF-alpha, IFN-gamma and IL-6. We tested the hypothesis that Be-stimulation might induce the production of TNF-alpha by macrophage cell lines. We observed that H36.12j cells (12j), a mouse hybrid macrophage cell line, but not other mouse and human macrophage cell lines, produced TNF-alpha upon Be-stimulation. The response was maximal at 100 microM BeSO4 and did not occur when 12j cells were stimulated with either aluminum sulfate or cobalt sulfate. Beryllium-stimulated the production of 725+/-25 pg/ml (mean +/- SEM) TNF-alpha protein by 12j cells as measured by ELISA of culture supernatants after 24 h. As measured by RT-PCR, Be-stimulated 12j cell TNF-alpha protein production was accompanied by an increased intracellular TNF-alpha mRNA at 3 and 24 h. The addition of 10U or 100U of rMu-IFN-gamma to Be-stimulated 12j cells further increased TNF-alpha production 1.5-4 fold (1.6+/-0.1 ng/ml) respectively. Bacterial lipopolysaccharide (LPS, 1 microg/ml) stimulated production of TNF-alpha in 12j culture supernatants after 6 h (515+/-151 pg/ml). This early versus late TNF-alpha production suggests that LPS and Be both stimulate 12j cell TNF-alpha synthesis, but through different pathways. We report for the first time, the direct effects of Be stimulation on the ability of 12j cells to produce TNF-alpha. The 12j cell line, contrasted with other macrophage hybrids that do not respond to Be-stimulation, may provide a useful tool to evaluate the mechanisms by which Be stimulates macrophage cytokine production, and by which T cell derived IFN-gamma amplifies TNF-alpha production in granulomatous diseases.

Beryllium-stimulated in vitro migration of peripheral blood lymphocytes.

Inhalation of beryllium (Be) induces both inflammatory and metal antigen-specific immune responses in the lungs characterized by mononuclear cell infiltration and granuloma formation (chronic beryllium disease, CBD). We tested the hypothesis that Be-salts might increase the in vitro migration of peripheral blood mononuclear cells (PBMC). PBMC are mixed cells, consisting of lymphocytes and monocytes. We compared their responses to populations of both purified blood lymphocytes, and purified blood monocytes. Purified blood monocytes and lymphocytes, isolated by Percoll gradients and centrifugal elutriation from normal human subjects (n = 6), were exposed to graded concentrations (0.01 to 100 microM) of BeSO4 or to the control metal-salt Al2(SO4)3. Migratory responses of stimulated PBMC were measured in Boyden Chambers. As controls, PBMC mixed cells or purified lymphocytes or purified monocytes were unstimulated or stimulated with a positive chemoattractant, Zymosan-A treated pooled, normal human serum (ZAS). The migration index (MI) was defined as the distance (micrometers) that cells migrated through a 5 micron filter. The MI for unstimulated PBMC mixed cells was 75+/-4 whereas the MI for ZAS-stimulated PBMC mixed cells was 124+/-4 (P < or = 0.05, Tukey-Kramer). The MI for BeSO4 -stimulated (100 microM) PBMC mixed cells was 136+/-4. The observed increase in the BeSO4-stimulated PBMC mixed cell migration was significant down to 0.1 microM BeSO4. BeSO4, BeCl2 and BeF2, tested at 100 and 10 microM, were equally effective at inducing PBMC mixed cell migration. Equimolar concentrations of Al2(SO4)3 were not as effective at inducing PBMC mixed cell migration, MI < 100 at 100 microM, and did not induce PBMC mixed cell migration at concentrations below 1 microM. The migration of purified monocytes through filters was not increased in response to either BeSO4 or Al2(SO4)3 compared to controls, but did respond to ZAS (MI = 100+/-4). Purified lymphocytes migrated in response to stimulation with all concentrations of BeSO4 tested (100 microM MI = 133+/-9), and Al2(SO4)3 (100 microM MI = 85+/-8). There were no significant differences in the MI for PBMC mixed cells or for purified lymphocytes at the concentrations of BeSO4 tested. Our data show that Be directly induces the in vitro migration of PBMC mixed cells and purified blood lymphocytes, and not purified blood monocytes, across a broad range of Be concentrations. This induction of migration was independent of the molecular form of the Be-salt. Inhaled Be, by promoting lymphocyte emigration to the lung, may create a microenvironment that favors a Be-antigen-specific T-lymphocyte response, chronic inflammation, and CBD.