High extracellular induced sputum haem oxygenase-1 in sarcoidosis and chronic beryllium disease.

BACKGROUND: Sarcoidosis and chronic beryllium disease (CBD) are inflammatory conditions in which oxidative stress state may be crucial for disease outcome. This study compares haem oxygenase-1 (HO-1) extracellular activity for the first time in patients with sarcoidosis or CBD and in healthy controls. MATERIALS AND METHODS: Induced sputum was recovered using a standard protocol. Pulmonary function tests (PFT) were performed by conventional methods. T lymphocyte subsets (CD4 and CD8) were measured by flow activated cell shorter (FACS). The HO-1 and nitrite levels were measured by a bilirubin-biliverdin reductase-dependent reaction and Greiss reaction respectively. Ferritin and iron levels were measured by enzymatic reaction and chemiluminometric immunoassay respectively. RESULTS: The mean percentage of lymphocytes was significantly higher in the 36 sarcoid patients compared with that in the 17 controls (P=0.001). The mean CD4/CD8 ratio was significantly higher in the sarcoid and the 10 CBD patients compared to that in controls (P=0.000 and 0.002 respectively), as was the mean HO-1 activity (P=0.045 and 0.041 respectively). The HO-1 activity did not differ with the sarcoidosis stage. The HO-1 level and PFT parameters were negatively correlated. The differences in mean nitrite, ferritin and iron levels were non-significant between the three groups. The HO-1 and ferritin levels were correlated (P=0.008). CONCLUSIONS: We succeeded in non-invasively measuring the activity of HO-1 from cells of airways in spite of its being an intracellular enzyme. The HO-1 levels in sarcoidosis and CBD were abnormally elevated.

Morphological and biochemical properties of alveolar fibroblasts in interstitial lung diseases.

The phenotype of alveolar-associated fibroblasts (Afb) in sarcoidosis (SA) and idiopathic pulmonary fibrosis (IPF) is unclear. In the present study, we characterized the cytoskeletal proteins and the contraction properties in alveolar-associated fibroblasts recovered by bronchoalveolar lavage (BAL) in the two diseases. Afb were studied from BAL cells in eight IPF and seven SA patients. Cytoskeletal proteins were identified by ELISA and immunofluorescent methods. Biochemical measurements were done by dry chemistry. Contraction was performed by a gel contraction assay. Afb alpha-SM actin measured by ELISA was higher in IPF than in SA (p = 0.042). Vimentin, desmin, myosin, and fibroblast markers were expressed equally. Only in IPF did the Afb reveal the myofibroblast phenotype showing alpha-SM actin immunofluorescence labeling and, by electron microscopy, filaments with associated dense bodies with rough endoplasmic reticulum. Gel contraction showed that cells in IPF contracted significantly more than in SA (p = 0.046 IPF versus SA). The addition of ET-1 increased contraction in all groups. Dry chemistry analysis showed higher levels (p = 0.0065) of creatine phosphokinase (CPK), lower levels of glucose (p = 0.0082), and similar levels of Ca(2+) and lactate in the IPF and SA Afb. Dinitrofluorobenzene (DNFB), a potent inhibitor of CPK, completely abolished spontaneous cell contraction. Afb differentiates into myofibroblasts with different biochemical and energetic properties in IPF. Moreover, Afb from IPF patients showed increased contractile properties. This may explain the difference in the behavior patterns and outcomes of the two diseases.

Effect of endothelin-1 on alpha-smooth muscle actin expression and on alveolar fibroblasts proliferation in interstitial lung diseases.

Endothelin-1 (ET-1) is a potent constrictor and mitogen peptide which is expressed in several pulmonary diseases. To elucidate the involvement of ET-1 in lung interstitial pathologic events, we assessed ET-1 secretion by alveolar macrophages (AM) and fibroblasts recovered from the bronchoalveolar lavage (BAL) of patients with idiopathic pulmonary fibrosis (IPF), sarcoidosis (SA) and from control subjects. We characterized in vitro alveolar fibroblasts of all subjects using monoclonal antibody specific to alpha-smooth muscle actin (alpha-SM actin) and human fibroblast marker. We also examined the effect of ET-1 on the fibroblasts' mitogenesis and on their cytoskeletal phenotype. The AM recovered from IPF patients showed increased spontaneous secretion of ET-1 compared with cells from SA and control subjects. The expression of alpha-SM actin in the fibroblasts from IPF patients was significantly higher than in SA fibroblasts and normal lung fibroblasts. Assessing alveolar fibroblasts purity revealed a negative staining for alpha-SM actin in all SA and control fibroblasts, while alveolar fibroblasts recovered from IPF were 100% positive for alpha-SM actin, a reliable differentiation marker of myofibroblastic cells. Exposure of SA alveolar fibroblasts to ET-1 resulted in an increased expression of alpha-SM actin. Addition of exogenous ET-1 to alveolar fibroblasts culture stimulated DNA synthesis and proliferation in all groups. Moreover, neutralization of ET-1 by monoclonal antibody was shown to decrease 3H-thymidine incorporation in fibroblasts cultured with AM supernatants. These results suggest possible interactions between AM, myofibroblasts and fibroblasts in interstitial lung diseases (ILD). By modulating alpha-SM actin expression and exertion of the mitogenic effect on alveolar fibroblasts, ET-1 might play an important role in the fibrogenesis of ILD.

Pulmonary alveolar proteinosis in Israel: ethnic clustering.

BACKGROUND: Pulmonary alveolar proteinosis is a rare disease in which a surfactant-like phospholipid-rich protein accumulates in the lungs. The disease is amenable to effective therapy by total lung lavage. OBJECTIVES: To investigate the prevalence, ethnic distribution and course of PAP in Israel. METHODS: A countrywide survey was conducted during which pulmonologists were questioned about patients with PAP. The patients were examined and their charts, radiological images, pathological slides and physiological data were reviewed. RESULTS: The survey yielded 15 patients (8 females) during the period 1976-98 (14 in the last decade), giving a prevalence of 3.7 x 10(6) and an incidence of 0.36 x 10(6)/year. Mean age of the patients was 33 +/- 13 years (range 0.5-46 years). Seven patients were North African (two were siblings), four were from Iraq and two were Arabs; there was only one Ashkenazi Jew (a child). Symptoms at the onset were dyspnea and chest pain. Spontaneous remission occurred in at least 3 patients, and 10 patients required 1-4 bronchoalveolar lavage treatments. The subjective and physiological response was favorable, but there was less consistent radiological improvement. CONCLUSION: The prevalence of PAP in Israel is approximately 3.7 x 10(6). Most cases occurred in Jews who had immigrated from North Africa or Iraq, and two were siblings. The prevalence among the Arab population appears to be similar. This clustering suggests the existence of a genetic predisposition. The course of the disease appears to be similar to that reported elsewhere.

Effect of IL-6 on alveolar fibroblast proliferation in interstitial lung diseases.

Alveolar macrophage-fibroblast interaction may be involved in the pathogenesis of interstitial lung diseases (ILD). Herein, we compared IL-6 secretion from alveolar macrophages (AM) and alveolar fibroblasts (AFb) recovered from patients with sarcoidosis (SA) and with diffuse interstitial fibrosis (DIF). Moreover, we evaluated the effect of IL-6 on the in vitro AFb proliferation in both diseases. AM and AFb from SA patients showed increased spontaneous secretion of IL-6 compared with cells from DIF subjects. Tumor necrosis factor-alpha (TNFalpha) and interleukin-1 (IL-1) enhanced IL-6 secretion and IL-6 mRNA transcription in AFb of SA patients. Addition of anti-IL-6 MoAbs increased AFb proliferation capacity in SA, but suppressed it in DIF. These results show that only SA AM and AFb secrete high levels of IL-6 which have suppressive effect on AFb proliferation. This may indicate a potential role of IL-6 in the fibrogenesis of ILD.

Bronchoalveolar lavage--a sensitive tool for early diagnosis of pulmonary involvement in rheumatoid arthritis.

Bronchoalveolar lavage (BAL) was performed to assess the nature of pulmonary involvement in 12 asymptomatic nonsmoking patients with rheumatoid arthritis (RA). All 12 patients had normal lung function tests, including diffuse capacity for carbon monoxide and normal blood gases. Four patients (33%) had mild basilar interstitial changes on chest radiographs. In these 4 patients an elevated lymphocytic count in BAL fluid (30.7 +/- 8.3%) was found, as compared to the 8 patients with normal chest roentgenograms (7.2 +/- 1.9%; p less than 0.001). We suggest that BAL may be used as a sensitive tool for early diagnosis of pulmonary involvement in patients with RA.