Bronchoalveolar lavage cell count and differential are not reliable indicators of amiodarone-induced pneumonitis.

Amiodarone-induced interstitial pneumonitis is a serious, frequently fatal untoward effect of a commonly used antiarrhythmic agent. Recent reports suggest that bronchoalveolar lavage (BAL) fluid cellular analysis might be used to diagnose amiodarone-induced pneumonitis. The purpose of this study was to determine if the diagnosis of amiodarone-induced pneumonitis could be made by patient history, pulmonary function evaluation, and examination of BAL fluid. We studied five groups of patients. Three of the five groups received amiodarone: patients receiving amiodarone without evident lung toxic reaction, patients with amiodarone-induced pneumonitis, and amiodarone-treated patients diagnosed as having other pathologic processes involving the lung. The two other groups examined were healthy volunteers and patients with interstitial lung disease from causes other than amiodarone. Pulmonary function tests included vital capacity (FVC), first second forced exhaled volume (FEV1), total lung capacity (TLC), and diffusing capacity for carbon monoxide (DCO). BAL fluid analysis included total and differential cell counts. We found that amiodarone-induced interstitial pneumonitis was not associated with an alteration in pulmonary function or BAL cellular composition which could permit its distinction from amiodarone-treated patients diagnosed as having an unrelated pulmonary process or patients with interstitial lung disease from other causes. The most frequent abnormality encountered in patients with amiodarone toxicity was a reduction in the percentage of macrophages in the differential cell count. The sensitivity, specificity, and predictive value of this finding was 82 percent, 69 percent, and 69 percent, respectively. The sensitivity, specificity, and predictive value of a > or = 15 percent reduction in DCO was 44 percent, 50 percent, and 36 percent, respectively. We conclude that amiodarone-induced interstitial pneumonitis remains a diagnosis of exclusion, and the role of BAL fluid analysis is to narrow the differential diagnosis through microbiologic culture and cytologic examination.     

Bronchoalveolar lavage cell data in alveolar proteinosis.

In bronchoalveolar lavage fluid (BAL) from nine patients with alveolar proteinosis (AP), total and differential cell count and T-lymphocyte phenotyping were done and compared with those in 12 healthy volunteers comparable as to age and tobacco consumption. Although total cell count was not significantly different from that in control subjects, the most prominent feature in patients was an increase in the number of CD4 and CD8 T-lymphocytes within the alveoli. Conversely, the macrophage population was significantly reduced. The ratio of CD4/CD8 T-lymphocytes tended to be high, but this increase did not reach statistical significance. The pathophysiologic mechanism and the meaning of these alveolar cell changes in AP remain to be elucidated.     

Bronchoalveolar lavage cell profiles in Wegener's granulomatosis.

Pulmonary involvement due to Wegener's granulomatosis (WG) can present radiologically either as diffuse infiltrates or as nodular and linear opacities. Clinical experience suggest that these radiological patterns are associated with different bronchoalveolar lavage (BAL) cell profiles, but this has not been examined formally. We compared the BAL cell profile in eight WG patients with diffuse infiltrates on chest X-ray, indicative of highly active pneumonitis, with corresponding findings in 37 patients with nodular, linear and focal low-attenuation infiltrates on high-resolution computed tomography (HRCT) which reflected low-grade, mainly interstitial disease. A control group was composed of 11 patients with pulmonary sarcoidosis. Diffuse infiltrates occurred in association with high systemic disease activity and featured a neutrophilic BAL profile in the presence of generally normal BAL lymphocytes. HRCT findings suggestive mainly of interstitial disease were associated with either a lymphocytic BAL cell profile or a normal cell pattern. Patients with a lymphocytic cell profile generally had a preferential elevation of CD4+ cells in the BAL in the presence of a normal CD4/CD8 ratio in the blood. This was a common feature of WG and pulmonary sarcoidosis. In conclusion, highly active pneumonitis and pulmonary disease of low or moderate activity in WG are associated with disparate BAL cell profiles. It remains to be examined whether the preferential elevation of CD4+ cells in the latter condition reflects a common pathogenetic role of this subset of cells in WG and pulmonary sarcoidosis.     

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

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

Bronchoalveolar lavage and transbronchial biopsy in spondyloarthropathies.

Fourteen patients (12 men, 2 women) with spondyloarthropathies underwent bronchoalveolar lavage (BAL), transbronchial biopsy (TBB) and other respiratory investigations. BAL revealed lymphocytosis and increased nonaltered neutrophil polynuclears in a smoker and an isolated lymphocytosis in one patient with restrictive syndrome and radiographic apical fibrosis. TBB showed interstitial fibrosis in the 2 patients and in 3 others who are all nonsmokers and among whom 2 had a restrictive syndrome. Subclinical alveolitis in spondyloarthropathies is absent. Interstitial fibrosis is not rare and its frequent association in a restrictive syndrome suggests a mechanical origin.     

Bronchoalveolar lavage in immunocompromised patients. Clinical and functional consequences.

Fiberoptic bronchoscopy and bronchoalveolar lavage are major tools in the diagnosis of acute pneumonia in immunocompromised patients. We conducted a prospective study to assess the morbidity associated with this procedure in 14 patients with AIDS and 16 patients with drug-induced immunosuppression. No patient had a PaO2 lower than 70 mm Hg with additional oxygen. Clinical data, chest roentgenogram, pulmonary function test, forced vital capacity, forced expiratory volume in one second, and arterial blood gases were recorded before and after bronchoscopy. Arterial oxygen saturation was monitored during the procedure, and initial, lowest, and final saturation values were noted. The patients were separated into three groups on the basis of chest roentgenographic findings. No procedure-induced pneumonia or need for tracheal intubation occurred. Minor clinical symptoms induced by the lavage in seven patients resolved spontaneously. By contrast, mean SaO2 decreased markedly during the procedure from 94 +/- 3 to 87 +/- 5 percent (p less than 0.0001) and returned to only 89 +/- 5 percent at the end of the procedure. Lowest SaO2 during the procedure and final SaO2 correlated poorly with initial SaO2 but correlated well with initial FVC and FEV1 (p less than 0.01). The PFT values were lower following bronchoscopy. O2 desaturation was more pronounced in patients with severe roentgenographic abnormalities. No significant differences were found between the three groups of patients, or between the AIDS and DII patients in terms of changes in PFT values. We conclude that in immunocompromised patients, bronchoscopy with BAL induces severe arterial oxygen desaturation which is correlated with initial PFT and chest roentgenographic findings, and most of these abnormalities are transient and do not lead to major complications.     

Bronchoalveolar lavage cell and lymphocyte phenotype profiles in healthy asbestos-exposed shipyard workers

The cellular and lymphocyte phenotypic composition of bronchoalveolar lavage (BAL) fluid and peripheral blood (PB) from 15 healthy, nonsmoking, asbestos-exposed shipyard workers (AEW) and 10 nonsmoking, age-matched unexposed workers (UEW) were compared. None of the AEW had clinical, radiographic, or physiologic evidence of asbestosis, but six had radiographic evidence of pleural plaques and/or thickening. The mean duration of asbestos exposure was 16.3 +/- 2.3 yr, and the mean period since exposure was 10.8 +/- 0.5 yr. All but three of the AEW and none of the UEW had asbestos bodies detected in the first 20 ml of BAL fluid recovered (0.1 to 35 asbestos bodies/ml). The AEW had a significantly higher mean percentage (19.1 +/- 2.8% versus 9.7 +/- 1.6%) and concentration (31.6 +/- 5.2 x 10(3) cells/ml versus 14.7 +/- 2.5 x 10(3) cells/ml) of BAL lymphocytes compared with that in the UEW, with an increased mean concentration of each phenotype measured. In PB, the mean lymphocyte concentration was also higher in the AEW than in the UEW (2.0 +/- 0.3 x 10(3) cells/ml versus 1.5 +/- 0.3 x 10(3) cells/ml), but the difference was not statistically significant, and there was no increase of any phenotype measured. BAL lymphocytosis did not correlate with exposure history or BAL asbestos body count, but was greater in AEW with pleural abnormality (30.1 +/- 2.9% versus 11.8 +/- 1.6%). BAL concentrations of CD-20, CD-3, and CD-4, but not of CD-8 cells were significantly increased compared with those in the AEW without pleural abnormality. Further longitudinal studies are needed to determine the prognostic significance of these findings.     

Pulmonary cell populations in the immunosuppressed patient. Bronchoalveolar lavage findings during episodes of pneumonitis

Bronchoalveolar lavage (BAL) cell populations were determined in 47 immunosuppressed patients during episodes of pulmonary disease. Thirty six patients had AIDS and 11 had conventional causes of immunosuppression. Pulmonary disease was due to a variety of infectious and noninfectious causes and was similar in both groups. In the AIDS patients, the mean BAL cell proportions were 64.2 +/- 3.7 percent alveolar macrophages (MACS), 28.7 +/- 3.4 percent lymphocytes, 3.5 +/- 1.8 percent polymorphonuclear cells (PMN) and 1.6 +/- 0.6 percent eosinophils (EOS). The non-AIDS group had similar findings in the BAL, with 59.3 +/- 8.3 percent MACS, 34.8 +/- 7.2 percent lymphocytes, 5.5 +/- 1.7 percent PMN and 0.4 +/- 0.2 percent EOS. The most striking finding in each group was a significant increase in both the proportion and absolute number of lymphocytes compared to controls. This was in marked contrast to the peripheral blood findings of lymphopenia. There was no characteristic cell profile diagnostic of any specific pulmonary disease. There was also no direct relationship of the cells present to respiratory symptoms, roentgenographic abnormalities or survival from pulmonary disease. This study demonstrates that although there was wide individual variation in lavage findings, a local pulmonary inflammatory reaction consisting predominantly of lymphocytes occurs in the immunosuppressed host during episodes of lung disease. The significance of this lymphocyte alveolitis and the complex host pathogen interaction responsible for determining the cell populations present in the lungs of these patients requires further study.     

Bronchoalveolar lavage analysis in Wegener's granulomatosis. A method to study disease pathogenesis

A prospective analysis of bronchoalveolar lavage (BAL) in 13 patients with Wegener's granulomatosis (WG), 20 disease control subjects with idiopathic pulmonary fibrosis (IPF), and 24 normal control subjects was conducted to (1) evaluate the quality of the alveolar inflammatory response associated with active WG; (2) determine whether antineutrophil cytoplasmic antibody (ANCA) is present in alveolar fluid and produced in the lungs of patients with WG; and (3) determine whether inhaled particles or infectious agents may play an etiologic role in WG. BAL in untreated active WG had a marked increase in neutrophils (mean = 42% of total WBC count), and usually in eosinophils (mean = 4%) compared with that in normal control subjects (1.6% neutrophils, 0% eosinophils), and untreated WG in remission (5.9% neutrophils, 0% eosinophils). Disease control subjects with IPF, a process known to be associated with neutrophilic alveolitis, had an increased population of neutrophils (15.4%) and eosinophils (2.7%) in BAL. Leukocyte remnants, as well as intact leukocytes, could be identified within BAL macrophages in the patients with WG and IPF, and rarely in the normal control subjects. Normal subjects and control patients with IPF were all negative for ANCA in serum, whereas ANCA was found in serum and BAL in all patients with active WG who had generalized disease. Protein analysis of BAL revealed a disproportionate increase in the IgG to albumin ration compared with serum values (IgG index) in patients with active untreated disease. The increase in the IgG index suggests that IgG with ANCA reactivity is produced by pulmonary lymphoid tissue. An infectious agent in BAL was not identified by any of the techniques applied in this study.(ABSTRACT TRUNCATED AT 250 WORDS)     

The repeatability of nonbronchoscopic bronchoalveolar lavage differential cell counts.

Airway inflammation in children can be assessed by nonbronchoscopic bronchoalveolar lavage (BAL). Little is known about the repeatability of cell counts in the BAL obtained. Children (n=43) attending for elective surgery were studied. Cell counts were obtained following a nonbronchoscopic lavage. Two samples were obtained with either: 1) the catheter wedged in the same position (n=21) or 2) the catheter reinserted and wedged again (n=22). Slides (n=30) from nonbronchoscopic lavage samples were selected at random and two independent observers counted 500 cells on each slide on two occasions. The repeatability of the lavage sampling and cell counting was assessed for different cell types. The inter- and intra-observer repeatability for the differential cell counting demonstrated that there was good repeatability for all cell types except lymphocytes (interobserver: Lin's concordance coefficient 0.42; repeatability coefficient 0.66). Quantification of eosinophil (%) was highly repeatable using either method (Lin's concordance coefficient 1) 0.99, 2) 0.95; repeatability coefficient 1) 0.58, 2) 1.36). Nonbronchoscopic lavage is a repeatable technique for the quantification of eosinophils. Variation in the sampling method can be reduced by taking two separate samples and averaging the differential cell counts. Furthermore, increasing the number of cells counted should ensure accurate quantification of lymphocytes.     

Bronchoalveolar lavage in alcoholic liver cirrhosis. T-lymphocyte subsets and immunoglobulin concentrations.

The purpose of this study was to determine the phenotype profiles of immune effector cells and the concentrations of immunoglobulins in the lower respiratory tract of non-smoking patients with alcoholic liver cirrhosis (ALC). Nine nonsmoking patients with liver biopsy-proved ALC (grade B or C cirrhosis in Child's classification), free of clinical pulmonary symptoms, and with normal chest roentgenogram were included in the study. The control group included 12 healthy nonsmokers. Each patient had fiberoptic bronchoscopy with bronchoalveolar lavage (BAL). The number of T cells and of lymphocyte subpopulations was determined by immunofluorescence studies using monoclonal antibodies that were specific for CD3, CD4, and CD8 markers. Patients with ALC exhibited a dramatically increased percentage of CD8+ cells in BAL that induced a low CD4/CD8 ratio (0.96 +/- 0.15 vs 1.8 +/- 0.12 in healthy controls). Further characterization of lymphocyte subsets' dual immunofluorescence analysis demonstrated that most of the CD8+ alveolar lymphocytes had a phenotype of cytotoxic cells (CD8+ CD11b-; 48 percent +/- 13 in ALC vs 10 percent +/- 5 in controls). ALC was associated with an appreciable alveolar-capillary "leak" as demonstrated by a significant increase in BAL fluid albumin. In addition, the concentrations of immunoglobulins in BAL fluid were significantly greater in ALC than in controls. However, the relative (to albumin) coefficient of excretion of IgG, A, and M in and alpha 2-macroglobulin BAL fluid was not significantly different between controls and ALC. Our results indicate that increased proportions of CB8+ and especially of CD8+ CD11b- cells are a common feature in the lower respiratory tract of nonsmoking patients with ALC. These changes may be of potential functional importance in the regulation of the local pulmonary immune response in ALC.     

Bronchoalveolar lavage lipids during development of bleomycin-induced fibrosis in rats. Relationship to altered epithelial cell morphology

Alterations in the structure and function of alveolar epithelial cells may contribute to the interstitial fibrosis that can develop following lung injury. The present studies were undertaken to determine if alterations observed in alveolar epithelial cell morphology and cytoskeletal composition are reflected in the profile of bronchoalveolar lavage (BAL) lipids recovered from injured lung. BAL protein and lipid analyses were performed on fluids recovered from control rats and from rats 7, 14, and 28 days after intratracheal instillation of bleomycin, an antineoplastic agent well-known to cause pulmonary interstitial fibrosis. There were increases in recovery of total protein, nonpolar lipid, polar lipid, and phospholipid following bleomycin treatment. The recovery of saturated phosphatidylcholine was increased, but recovery of a second surfactant phospholipid, phosphatidylglycerol, was unchanged, resulting in a significant change in their ratio. The recoveries of cholesterol, cholesterol ester, and triglyceride also were elevated. Changes in the proportional recoveries of neutral lipids, such as cholesterol and saturated phospholipids, could partly explain concurrent reductions in lung compliance that have been described. Changes in lavage lipids paralleled both the process of alveolar reepithelialization and altered expression of alveolar epithelial cell cytoskeletal proteins. Changes in lipid metabolism by alveolar epithelial cells following bleomycin-induced lung injury may be responsible for altered lavage lipid recovery and may directly be related to processes that take place during alveolar type II cell hyperplasia followed by transition to type I cells. BAL lipid analyses thus may provide a relatively noninvasive way of assessing these events.     

Bronchoalveolar lavage in amiodarone pneumonitis. Cellular abnormalities and their relevance to pathogenesis

To investigate the contribution of direct cytotoxicity and immune-mediated hypersensitivity to the pathogenesis of amiodarone pneumonitis, we evaluated cells recovered by bronchoalveolar lavage from 13 patients with amiodarone pneumonitis. Alveolar macrophages from all patients contained two types of abnormal inclusions: small clear vacuoles and large phagolysosomes containing phospholipid in lamellar structures, abnormalities previously attributed to direct cytotoxicity from amiodarone. However, these changes were always associated with abnormalities in the numbers and types of immune and inflammatory cells present in the lower respiratory tract, which closely resemble those seen in hypersensitivity pneumonitis associated with inhaled antigens. Following discontinuation of amiodarone and institution of corticosteroid therapy, clinical improvement correlated with a return toward normal in the pattern of inflammatory cells present in the lung, although alveolar macrophages continued to display evidence of drug-induced cytotoxicity. These findings support the possibility that a cell-mediated immune response usually plays a role in the pathogenesis of amiodarone pneumonitis, although direct cytotoxicity may predispose these patients to the development of this abnormal immune response.     

Asbestosis. Bronchoalveolar lavage fluid proteins and their relationship to pulmonary epithelial permeability

We measured levels of albumin and immunoglobulins in serum and bronchoalveolar lavage (BAL) fluid in 28 men with asbestosis and 11 control subjects. The half-time clearance of inhaled diethylene triamine pentacetate labelled with technetium-99m (99mTc-DTPA) from the lungs (t1/2LB) was measured in 26 patients with asbestosis and in 31 normal nonsmoking controls. In those individuals in whom immunoglobulins were detected in BAL fluid, the mean IgG:albumin ratio in BAL fluid was 0.30 (range, 0.11 to 0.97), significantly less than the ratio of 0.43 (0.28 to 0.66) in control subjects (p less than 0.05). There was no significant difference in IgA:albumin ratios between patients and control subjects. The mean BAL:serum albumin ratio in patients with asbestosis was 2.3 X 10(-3) (range, 0.2 to 9.5 X 10(-3), significantly greater than the ratio of 1.2 X 10(-3) (0.5 to 2.0 X 10(-3] in control subjects (p less than 0.02). The t1/2LB was significantly shorter in both smokers and nonsmokers with asbestosis, compared with 31 normal nonsmoking controls, but there were no relationships between t1/2LB and BAL:serum albumin ratio or any other BAL protein levels in either smokers or nonsmokers with asbestosis.     

Alveolitis of pulmonary asbestosis. Bronchoalveolar lavage studies in crocidolite- and chrysotile-exposed individuals

Bronchoalveolar lavage (BAL) findings in 27 individuals with crocidolite- or chrysotile-induced asbestosis were compared to BAL findings in 29 unexposed control subjects. Alveolitis, defined as an increase in the proportions and/or absolute numbers of inflammatory cells present in BAL fluid compared to values in control subjects, was present in 26 (96 percent) subjects with asbestosis. Most exhibited a neutrophil-eosinophil alveolitis, with neutrophil proportions increased to 7.4 +/- 0.7 percent and eosinophil proportions increased to 2.2 +/- 0.4 percent, compared to 2 +/- 0.5 percent and 0.4 +/- 0.01 percent, respectively, in control subjects (p less than 0.01 for both neutrophils and eosinophils). An increase in the total number of neutrophils and eosinophils per ml of lavage fluid was also seen (neutrophils 23 +/- 5 and eosinophils 13 +/- 4 per ml; p less than 0.05 compared to control subjects). Severity of the alveolitis, defined by the neutrophil or eosinophil proportions, was independent of a history of exposure to cigarette smoke. The pattern and severity of alveolitis in crocidolite- and chrysotile-induced asbestosis were similar. There was a significant correlation between duration of exposure to asbestos and neutrophil proportions (p less than 0.01). No significant difference in the severity of the alveolitis was observed between individuals with radiologic and physiologic evidence of asbestosis compared to those with asbestos exposure and crackles alone, suggesting that, in asbestosis as in other chronic interstitial lung diseases, radiologic and physiologic parameters do not reflect the severity of the alveolitis. This study demonstrates that a neutrophil-eosinophil alveolitis is present in individuals with crocidolite- and chrysotile-induced asbestosis, that this alveolitis is independent of cigarette smoking, and that the severity of the BAL changes is not reflected in radiologic and physiologic changes.     

A technique for accurate use of CD4+ cell counts

Despite uncertainty over their reliability, CD4+ cell counts are used extensively in both clinical and research settings to document progression in HIV infection. We examined, therefore, whether the performance of a simple statistical test would facilitate greater accuracy in the use of this marker. CD4+ cell count data were collected from a cohort of deceased (N = 60) and living HIV-positive gay men (N = 100). Pearson's product moment correlation coefficients were calculated for each individual in order to examine the association between CD4+ counts and time since diagnosis. Correlations of 0.7 or greater were obtained in approximately 50 percent of cases in each cohort. For these individuals, CD4+ cell counts were deemed to be a reliable indicator of rate of progression. The results suggest that the proposed technique ensures greater precision in the use of CD4+ cell counts and that the technique cna be used in individuals with either complete (deceased patients) or partial (living patients) CD4+ data.     

Amiodarone pneumonitis. Bronchoalveolar lavage findings in 15 patients and review of the literature.

Amiodarone (Am) pneumonitis is currently a common and potentially severe adverse reaction, the accurate diagnosis of which remains difficult to establish. OBJECTIVES: To determine the contribution of bronchoalveolar lavage (BAL) in the diagnostic workup of patients suspected of having Am pneumonitis. METHODS: Diagnosis of Am pneumonitis was established on the basis of (1) development of recent symptoms and pulmonary opacities while receiving the drug, (2) exclusion of other possible causes, and (3) improvement following cessation of Am and/or steroid therapy. (4) Confirmatory changes were obtained by histopathologic examination in eight cases. BAL was performed in each patient at the time of initial evaluation. RESULTS: Am pneumonitis was diagnosed in 15 consecutive patients between 1985 and 1991. The disease was associated with significant morbidity and mortality. Six patients died; four died of Am pneumonitis. A neutrophilic BAL was found in nine patients (average PMN = 26.6 percent). A mixed pattern (lymphocytic + neutrophilic) was seen in four patients (average: Ly = 19.9 percent; PMN = 11.9 percent). Two patients had a normal BAL. No patient had a lymphocytic pattern. A low CD4+/CD8+ ratio was seen in two patients. A literature survey indicated 70 cases of Am pneumonitis with detailed information on BAL. The BAL pattern was mixed in 23 (33 percent), neutrophilic in 18 (26 percent), lymphocytic in 15 (21 percent), and normal in 14 (20 percent). No correlation was found between BAL pattern and prognosis. Also, BAL pattern was related neither to daily or total dose of Am nor to duration of treatment with Am. CONCLUSION: The cellular profile of BAL in Am pneumonitis is highly variable, and no cellular pattern of BAL seems to be predictive of a detrimental outcome or of irreversible fibrosis. Aside from excluding other illnesses, and due to its extreme variability, the contribution of BAL differential in the initial workup of patients suspected of having Am pneumonitis is limited.     

Electronic platelet counting after isopycnic differential centrifugation a simple rapid and accurate method

A semi-automatized platelet counting procedure with the use of a Coulter Counter is described. Its originality consists in providing an electronic method of counting of the platelets after a differential centrifugation of the blood sample previously diluted with a hypertonic NaCl solution (density 1.053) which is isopycnic to platelet density. This procedure allows elimination of red and white cells without loss of platelets in the supernatant. The final platelet number can be calculated without further corrections. The method is quick and does not require specially skilled technicians. A single technician can perform 40 counts in one hour. The reproductibility of the method is excellent and the coefficient of variation 2,4%. The accuracy and feasibility of the method is also sustained by two years' experience in an haematological routine laboratory.     

Bronchoalveolar lavage cells from sarcoidosis patients and healthy controls can efficiently present antigens.

OBJECTIVES: The interaction between antigen-presenting cells (APC) and T lymphocytes, that recognize the antigen-HLA complex using its T cell-receptor for antigen, is of crucial importance for a subsequent specific immune response. In patients with pulmonary sarcoidosis, the local antigen-presenting capacity in the lungs has been suggested to be abnormally enhanced, and implicated in the immunopathogenesis of the disease. This study was aimed at increasing the understanding of the capacity to present antigens by APC in the lung compartment. DESIGN AND SUBJECTS: We used bronchoalveolar lavage (BAL) cells and paired peripheral blood mononuclear cells (PBMC) of six sarcoidosis patients and two healthy controls to stimulate in total eight well characterized T-cell clones with known HLA and antigen specificities. All subjects were HLA typed. RESULTS: BAL cells of sarcoidosis patients as well as of healthy controls efficiently induced proliferation of the relevant T-cell clone in an HLA-restricted manner when adding either intact antigen or antigenic peptides. CONCLUSIONS: BAL cells have the capacity to process and present antigens adequately, irrespective of whether they are derived from healthy individuals or from patients with sarcoidosis, implying the alveolar space as an important location for active immune reactions.