Alveolar Macrophages In Sarcoidosis Research Articles

Functional characterization of small and large alveolar macrophages in sarcoidosis and idiopathic pulmonary fibrosis compared with non-fibrosis interstitial lung diseases.

Sarcoidosis is a granulomatous disease that mostly affects the lungs. Advanced tissue injury caused by this disease can progress to pulmonary fibrosis with similar characteristics shared with idiopathic pulmonary fibrosis (IPF). The initial presentations of both sarcoidosis and IPF may be shared with other interstitial lung diseases (ILDs). Two populations of macrophages have been described in the alveolar space: small alveolar macrophages (AMs) and large alveolar macrophages. Despite their protective function, these cells may also play a role in the initiation and maintenance of inflammation leading to fibrosis. The aim of this study was the functional characterization of small and large AM subpopulations in sarcoidosis and IPF as a pathology with respectively mild and advanced tissue injury causing fibrosis, in comparison with non-fibrosis ILDs. Activation and adhesion surface markers as well as functions of small and large AMs isolated from bronchoalveolar lavage (BAL) were assessed by Flow Cytometry within patients with confirmed sarcoidosis (n= 14), IPF (n= 6), and non-fibrosis ILDs (n= 9). Our results showed that small AMs are immunologically more active, which may be important for airway inflammation. They are also proportionally more abundant in IPF, and therefore they may be more involved in a fibrosis process associated with the down-regulation of HLA-DR, LeuCAM, and CD62L expression. In Sarcoidosis, the inflammatory process appears to be associated with up-regulation of CD38 expression and oxidative burst activity. A relevant potential of the activation and adhesion markers as well as oxidative burst activity expressed on small and large AMs, in the perspective of differential diagnosis of sarcoidosis and IPF.

Application of Proteomics in Sarcoidosis.

Sarcoidosis is a multisystem disease with heterogeneity in manifestations and outcomes. System-level studies leveraging "omics" technologies are expected to define mechanisms contributing to sarcoidosis heterogeneous manifestations and course. With improvements in mass spectrometry (MS) and bioinformatics, it is possible to study protein abundance for a large number of proteins simultaneously. Contemporary fast-scanning MS enables the acquisition of spectral data for deep coverage of the proteins with data-dependent or data-independent acquisition MS modes. Studies leveraging MS-based proteomics in sarcoidosis have characterized BAL fluid (BALF), alveolar macrophages, plasma, and exosomes. These studies identified several differentially expressed proteins, including protocadherin-2 precursor, annexin A2, pulmonary surfactant A2, complement factors C3, vitamin-D-binding protein, cystatin B, and amyloid P, comparing subjects with sarcoidosis with control subjects. Other studies identified ceruloplasmin, complement factors B, C3, and 1, and others with differential abundance in sarcoidosis compared with other interstitial lung diseases. Using quantitative proteomics, most recent studies found differences in PI3K/Akt/mTOR, MAP kinase, pluripotency-associated transcriptional factor, and hypoxia response pathways. Other studies identified increased clathrin-mediated endocytosis and Fcγ receptor-mediated phagocytosis pathways in sarcoidosis alveolar macrophages. Although studies in mixed BAL and blood cells or plasma are limited, some of the changes in lung compartment are detected in the blood cells and plasma. We review proteomics for sarcoidosis with a focus on the existing MS data acquisition strategies, bioinformatics for spectral data analysis to infer protein identity and quantity, unique aspects about biospecimen collection and processing for lung-related proteomics, and proteomics studies conducted to date in sarcoidosis.

Derangement of Metabolic and Lysosomal Gene Profiles in Response to Dexamethasone Treatment in Sarcoidosis

Glucocorticoids (GCs) play a central role in modulation of inflammation in various diseases, including respiratory diseases such as sarcoidosis. Surprisingly, the specific anti-inflammatory effects of GCs on different myeloid cells especially in macrophages remain poorly understood. Sarcoidosis is a systemic granulomatous disease of unknown etiology that occurs worldwide and is characterized by granuloma formation in different organs. Alveolar macrophages play a role in sarcoidosis granuloma formation and progressive lung disease. The goal of the present study is to identify the effect of GCs on transcriptomic profiles and the cellular pathways in sarcoidosis alveolar macrophages and their corresponding blood myeloid cells. We determined and compared the whole transcriptional signatures of alveolar macrophages from sarcoidosis patients and blood CD14+ monocytes of the same subjects in response to in vitro treatment with dexamethasone (DEX) via RNA-sequencing. In response to DEX, we identified 2,834 genes that were differentially expressed in AM. Predominant pathways affected were as following: metabolic pathway (FDR = 4.1 × 10−10), lysosome (FDR = 6.3 × 10−9), phagosome (FDR = 3.9 × 10−5). The DEX effect on AMs is associated with metabolic derangements involving glycolysis, oxidative phosphorylation and lipid metabolisms. In contrast, the top impacted pathways in response to DEX treatment in blood CD14+ monocytes were as following; cytokine-cytokine receptor interaction (FDR = 6 × 10−6) and transcriptional misregulation in cancer (FDR = 1 × 10−4). Pathways similarly affected in both cell types were genes involved in lysosomes, cytoskeleton and transcriptional misregulation in cancer. These data suggest that the different effects of DEX on AMs and peripheral blood monocytes are partly dictated by lineage specific transcriptional programs and their physiological functions.

PPARγ Deficiency in Carbon Nanotube-elicited Granulomatous Inflammation Promotes a Th17 Response to a Microbial Antigen

BackgroundThe pathological consequences of interaction between environmental carbon pollutants and microbial antigens have not been fully explored. We developed a murine model of multi-wall carbon nanotube (MWCNT)-elicited granulomatous disease which bears a striking resemblance to sarcoidosis, a human granulomatous disease. Because of reports describing lymphocyte reactivity to mycobacterial antigens in sarcoidosis patients, we hypothesized that addition of mycobacterial antigen (ESAT-6) to MWCNT might elicit activation in T cells.MethodsMacrophage-specific peroxisome-proliferator-activated receptor gamma (PPARγ) knock out (KO) mice were studied along with wild-type mice because our previous report indicated PPARγ deficiency in sarcoidosis alveolar macrophages. MWCNT+ESAT-6 were instilled into mice. Controls received vehicle (surfactant-PBS) or ESAT-6 and were evaluated 60 days post-instillation. As noted in our recent publication, lung tissues from PPARγ KO mice instilled with MWCNT+ESAT-6 yielded more intensive pathophysiology, with elevated fibrosisResultsInspection of mediastinal lymph nodes (MLN) revealed no granulomas but deposition of MWCNT. MLN cell counts were higher in PPARγ KO than in wild-type instilled with MWCNT+ESAT-6. Moreover, the CD4:CD8 T cell ratio, a major clinical metric for human disease, was increased in PPARγ KO mice. Bronchoalveolar lavage (BAL) cells from PPARγ KO mice instilled with MWCNT+ESAT-6 displayed increased Th17 cell markers (RORγt, IL-17A, CCR6) which associate with elevated fibrosis.ConclusionThese findings suggest that PPARγ deficiency in macrophages may promote ESAT-6-associated T cell activation in the lung, and that the MWCNT+ESAT-6 model may offer new insights into pathways of lymphocyte-mediated sarcoidosis histopathology.

Dual Inhibition of Rip2 and IRAK1/4 Regulates IL-1β and IL-6 in Sarcoidosis Alveolar Macrophages and Peripheral Blood Mononuclear Cells.

Sarcoidosis is a multisystem granulomatous disease of unknown etiology that primarily affects the lungs. Our previous work indicates that activation of p38 plays a pivotal role in sarcoidosis inflammatory response. Therefore, we investigated the upstream kinase responsible for activation of p38 in sarcoidosis alveolar macrophages (AMs) and PBMCs. We identified that sustained p38 phosphorylation in sarcoidosis AMs and PBMCs is associated with active MAPK kinase 4 but not with MAPK kinase 3/6. Additionally, we found that sarcoidosis AMs exhibit a higher expression of IRAK1, IRAK-M, and receptor interacting protein 2 (Rip2). Surprisingly, ex vivo treatment of sarcoidosis AMs or PBMCs with IRAK1/4 inhibitor led to a significant increase in IL-1β mRNA expression both spontaneously and in response to TLR2 ligand. However, a combination of Rip2 and IRAK-1/4 inhibitors significantly decreased both IL-1β and IL-6 production in sarcoidosis PBMCs and moderately in AMs. Importantly, a combination of Rip2 and IRAK-1/4 inhibitors led to decreased IFN-γ and IL-6 and decreased percentage of activated CD4(+)CD25(+) cells in PBMCs. These data suggest that in sarcoidosis, both pathways, namely IRAK and Rip2, are deregulated. Targeted modulation of Rip2 and IRAK pathways may prove to be a novel treatment for sarcoidosis.

Interleukin-2 receptor expression in pulmonary granulomatous diseases

Interleukin-2 receptor expression (IL-2R) on monocytes and alveolar macrophages (AM) was determined in patients with sarcoidosis and pulmonary tuberculosis. In sarcoidosis and tuberculosis, IL-2R on monocytes was detectable, while it was undetectable in healthy controls. IL-2R on AM in sarcoidosis and tuberculosis was significantly increased as compared to healthy controls. IFN-gamma, which has been shown to be increased in sarcoidosis and tuberculosis as compared to healthy controls, induced IL-2R on monocytes in healthy controls, suggesting that IFN-gamma is at least in part responsible for the induction or enhancement of IL-2R on monocytes or AM in sarcoidosis and tuberculosis. Phorbol myristate acetate which is known to be protein kinase C (PKC) activator induced IL-2R on monocytes, and PKC inhibitor, H7, inhibited IFN-gamma-induced IL-2R on monocytes in healthy controls. Calcium ionophore, A23187, induced IL-2R on monocytes and calmodulin antagonist, W7, inhibited IFN-gamma-induced IL-2R on monocytes. Based on these results, it seems that not only the PKC pathway but also the calcium-calmodulin pathway is involved in IFN-gamma-induced IL-2R.

A study on assay method and dynamics of Fc-receptor activity of pulmonary alveolar macrophages in sarcoidosis

A study on assay method and dynamics of Fc-receptor activity of pulmonary alveolar macrophages in sarcoidosis

Tumour necrosis factor-α processing in interstitial lung disease: a potential role for exogenous proteinase-3

Tumour necrosis factor (TNF) blockade has become an important immunomodulatory therapy, particularly in patients refractory to conventional immunosuppression, but responses can be unpredictable. Understanding the complex biology of TNF processing may be key to predicting such responses and reduce unwanted side effects. TNF bioavailability is regulated partly by TNF-alpha converting enzyme (TACE) cleavage; however, it can also be cleaved by proteinase-3 (PR-3). We have demonstrated this mechanism previously in healthy human alveolar macrophages (AM), leading us to hypothesize that PR-3-mediated TNF processing may be an important mechanism in inflammatory lung disease. Furthermore, this may be more apparent in diseases with a neutrophil component typical of usual interstitial pneumonia (UIP), compared with sarcoidosis, where lymphocytes predominate. We isolated AM from patients with UIP and sarcoidosis and healthy subjects. We found increased TACE expression on AM in sarcoidosis. In contrast, TACE was not increased in UIP; we found increased cleavage of glutathione S-transferase-proTNF) substrate, relative to both sarcoidosis and healthy controls. Furthermore, cleavage was subject to inhibition by serine protease inhibitor, rather than a TACE inhibitor BB-3103. Cleavage was proportional to the number of neutrophils isolated from bronchoalveolar lavage, whereas there was an inverse relationship between neutrophils and BB-3103 inhibition. There was also increased PR-3 on the AM surface in UIP relative to healthy controls. These data provide evidence for PR-3-mediated cleavage in UIP, which may have implications for future therapeutic targeting of TACE.

Increased expression of the 25-hydroxyvitamin D(3)-1alpha-hydroxylase gene in alveolar macrophages of patients with lung cancer.

25-Hydroxyvitamin D(3)-1alpha-hydroxylase (1alpha-hydroxylase) plays a central role in calcium metabolism by synthesizing the active hormone 1alpha,25-dihydroxyvitamin D(3) in the kidney. Its increased expression in the extrarenal tissues has been found in alveolar macrophages in sarcoidosis but not in any other pathological conditions. We found that 1alpha-hydroxylase-mRNA in alveolar macrophages measured by semiquantitative RT-PCR was 2-fold greater in patients with lung cancer than in control subjects (0.61 +/- 0.20 vs. 0.34 +/- 0.11, respectively; P < 0.0001). When the clinical stages of lung cancer were divided into early (stage IA-IIIA) and advanced (stage IIIB and IV) and the expression of 1alpha-hydroxylase gene was compared among the control, early, and advanced groups, the advanced group showed the highest expression, followed by the early group, then the control group (0.34 +/- 0.11, 0.52 +/- 0.11, and 0.69 +/- 0.23 for control, early, and advanced groups, respectively; P < 0.0001). The 1alpha-hydroxylase-mRNA level was well correlated with serum 1alpha,25-dihydroxylase D(3) concentration and the 1alpha,25-dihydroxylase D(3) to 25-hydroxyvitamin D(3) ratio, but none of the findings related to calcium metabolism among the patients with lung cancer. Increased local production of 1alpha,25-dihydroxyvitamin D(3) may be associated with the pathological conditions, such as immunosuppression, in lung cancer.

Immunohistochemical Localization of B7 Costimulating Molecules and Major Histocompatibility Complex Class II Antigen in Pulmonary Sarcoidosis

Background: Alveolar macrophages (AM) of sarcoidosis have an enhanced capacity to mediate antigen-induced T lymphocyte proliferation. To induce an effective immune response, antigen-presenting cells have to not only present antigenic peptide with MHC molecules to T lymphocytes, but also express B7 costimulating molecules. Objective: The purpose of this study was to investigate the expression of B7 and MHC molecules in lung tissues from patients with sarcoidosis. Methods: We performed immunohistochemistry for B7-1, B7-2 and MHC class II antigens using transbronchial lung biopsy specimens obtained from patients with sarcoidosis and normal lung parenchyma obtained by lobectomy for solitary pulmonary nodule as controls. Results: B7-1, B7-2 and MHC class II antigen were expressed in epithelioid cells in granulomas in 14 (93.3%), 2 (13.3%) and 9 (60.0%) of 15 patients with sarcoidosis, respectively. These were also expressed in AM in 14 (93.3%), 5 (33.3%) and 12 (80.0%) of 15 patients with sarcoidosis, respectively. The positivitiy of B7-1 was significantly higher than that of B7-2 in both epithelioid cells and AM in sarcoidosis (p < 0.01). Positive signals for B7-1, B7-2 and MHC class II antigen were also found in AM in 9 (90%), 8 (80%) and 8 (80%) of 15 of controls, respectively. However, the intensity of positive signals for B7-1, but not B7-2 or MHC class II antigen in AM was significantly increased in sarcoidosis compared to controls (p < 0.05). Conclusions: These results suggested that epithelioid cells in granulomas and AM from patients with sarcoidosis had the capability to act as accessory cells and that the accessory function of these cells was shifted to B7-1 rather than B7-2 in sarcoidosis.

Repeatability of cough-related variables during fog challenges at threshold and suprathreshold stimulus intensity in humans

The Fas receptor (FasR) and the tumour necrosis factor (TNF) receptor 55/60 kDa (TNFR1) are recognized as apoptosis signalling receptors. They are known to be expressed by lymphocytes in association with immune regulation and immunological disorders. This study aimed to investigate the expression of FasR and TNFR1 by alveolar macrophages (AM) in patients with sarcoidosis. Bronchoalveolar lavage (BAL) was performed in 12 patients with active sarcoidosis and 11 control subjects. BAL cells were characterized by monoclonal antibodies using a peroxidase-antiperoxidase method. Both FasR and TNFR1 were expressed on a higher percentage of AM in sarcoidosis with respect to control subjects (mean +/-sem 40.8+/-3.1% versus 14.9+/-1.7%, p&lt;0.001 and 61.9+/-3.3% versus 23.1+/-4.1%, p&lt;0.001, respectively). There was a close relationship between the expression of FasR and TNFR1 on AM (r = 0.86, p&lt;0.001). The percentages of FasR+ AM and TNFR1+ AM were in direct proportion to the percentage of BAL lymphocytes (r = 0.75 and 0.84), the CD4/CD8 ratio (r = 0.78 and 0.78), and the percentage of the CD14+ AM subset (r = 0.77 and 0.87), p&lt;0.001 for all correlations. This study indicates that alveolar macrophages expressing apoptotic receptors are increased in patients with active sarcoidosis. Further studies are required to determine whether these alveolar macrophages from patients with sarcoidosis undergo apoptosis more readily than those from control subjects.

Increased expression of apoptosis signalling receptors by alveolar macrophages in sarcoidosis.

The Fas receptor (FasR) and the tumour necrosis factor (TNF) receptor 55/60 kDa (TNFR1) are recognized as apoptosis signalling receptors. They are known to be expressed by lymphocytes in association with immune regulation and immunological disorders. This study aimed to investigate the expression of FasR and TNFR1 by alveolar macrophages (AM) in patients with sarcoidosis. Bronchoalveolar lavage (BAL) was performed in 12 patients with active sarcoidosis and 11 control subjects. BAL cells were characterized by monoclonal antibodies using a peroxidase-antiperoxidase method. Both FasR and TNFR1 were expressed on a higher percentage of AM in sarcoidosis with respect to control subjects (mean +/-sem 40.8+/-3.1% versus 14.9+/-1.7%, p<0.001 and 61.9+/-3.3% versus 23.1+/-4.1%, p<0.001, respectively). There was a close relationship between the expression of FasR and TNFR1 on AM (r = 0.86, p<0.001). The percentages of FasR+ AM and TNFR1+ AM were in direct proportion to the percentage of BAL lymphocytes (r = 0.75 and 0.84), the CD4/CD8 ratio (r = 0.78 and 0.78), and the percentage of the CD14+ AM subset (r = 0.77 and 0.87), p<0.001 for all correlations. This study indicates that alveolar macrophages expressing apoptotic receptors are increased in patients with active sarcoidosis. Further studies are required to determine whether these alveolar macrophages from patients with sarcoidosis undergo apoptosis more readily than those from control subjects.

Increased expression of apoptosis signalling receptors by alveolar macrophages in sarcoidosis

Increased expression of apoptosis signalling receptors by alveolar macrophages in sarcoidosis

NEW MONOCLONAL ANTIBODIES AGAINST THE EPITHELIOID CELLS IN SARCOID GRANULOMAS

Sarcoidosis is a systemic granulomatous disease of unknown etiology. Extensive investigations of granulomas have suggested several possible causes, but these are still controversial. We previously developed an anti-Kveim monoclonal antibody, IHY-1, which reacts with sarcoid granulomas as well as with epithelioid cells of various granulomatous diseases including tuberculosis. In the present study, we developed 2 new anti-Kveim monoclonal antibodies, IHY-2 and IHY-3, which react with epithelioid cells in sarcoidosis but not in tuberculosis. These antibodies reacted with a small population of alveolar macrophages in sarcoidosis and hypersensitivity pneumonitis by flow cytometry, as well as with most epithelioid cells in sarcoid granulomas by immunoperoxidase technique, suggesting that these cells expressed the antigen present in the Kveim reagent. Although the antigens recognized by these antibodies have not yet been identified, these monoclonal antibodies might become useful tools to elucidate the etiology of sarcoidosis.

The source and role of RANTES in interstitial lung disease.

The chemokine "regulated on activation, normal T-cell expressed and secreted" (RANTES) is a potent eosinophil and lymphocyte attractant with particular preference for CD45RO+ T-cells and eosinophils. These cells accumulate in the lungs of patients with sarcoidosis and fibrosing alveolitis. The purpose of this study was to determine whether RANTES mediates the inflammatory cell influx in these diffuse lung diseases. Cell types and number of bronchoalveolar cells expressing RANTES protein were investigated by immunocytochemistry using lavage cells obtained from 22 patients and 11 control subjects. Subsequently, RANTES messenger ribonucleic acid (mRNA) was semiquantitated using reverse transcription polymerase chain reaction (RT-PCR) methodology in unseparated lavage cell pellets in 26 patients and 13 control subjects. Cells expressing RANTES mRNA were identified by in situ hybridization. RANTES protein expression in lower respiratory tract (LRT) cells was identified in all study groups. The percentage of RANTES+ lavage cells in sarcoidosis was higher than in controls. RANTES was localized in the cytoplasm, mainly in alveolar macrophages (CD68+ cells) in sarcoidosis, and both in alveolar macrophages and eosinophils in fibrosing alveolitis. The same cell types which expressed RANTES protein expressed RANTES mRNA, as assessed by in situ hybridization. Sarcoidosis patients had higher levels of RANTES mRNA than the other groups. RANTES protein was higher in individuals with abnormal lymphocyte numbers: RANTES protein and mRNA expression was significantly correlated with lavage CD45RO+ lymphocyte numbers. These results indicate that RANTES may mediate T-lymphocyte influx in diffuse lung disease, particularly sarcoidosis. Moreover, they suggest that the cellular source of RANTES is the alveolar macrophage in sarcoidosis, and both macrophages and eosinophils in fibrosing alveolitis.

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 thein vitroAFb 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-α (TNFα) 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.

Proliferation of mature and immature subpopulations of bronchoalveolar monocytes/macrophages and peripheral blood monocytes.

A continuous influx of peripheral blood monocytes (PBM) to the lung is thought to maintain the local population of alveolar macrophages (AM). However, local proliferation of a small subpopulation of AM has been demonstrated in animal studies and in humans. AM exhibit a great heterogeneity with regard to their morphology (cell size, shape of nucleus), immunophenotype (expression of CD14 and RFD9 antigen), and function. Part of this heterogeneity may be explained by the presence of different maturation stages of AM, ranging from small immature, CD14+ RFD9- PBM-like cells to large, CD14- RFD9+ mature AM. These findings prompted us to study whether proliferation of PBM and AM is related to their stage of maturation. The expression of the proliferation marker Ki-67 was studied in AM from both healthy volunteers and patients suffering from sarcoidosis. Using double immunofluorescence staining, we studied proliferation of immature, CD14+ AM, and mature, RFD9+ AM in sarcoidosis, and we compared this with PBM. A significantly larger percentage of AM in general expressed Ki-67 antigen in sarcoidosis (3.0 (median); range 1.1-5.5) as compared with healthy volunteers (0.8; 0.2-1.3). In sarcoidosis, proliferation was observed in both the immature and the mature subpopulation of AM. Proliferating PBM were rarely observed [less than 0.2% of the CD14+ mononuclear cells (MNC)] both in healthy volunteers and sarcoidosis patients. A small subpopulation of PBM showed a weak expression of RFD9 antigen (less than 1% of MNC). Interestingly, proliferation of PBM was concentrated in this subpopulation (15% of the RFD9+ MNC). These data show that even mature AM, which are generally thought to be terminally differentiated cells with little capacity to replicate, are able to proliferate, whereas a relatively very low percentage of their precursors in the blood circulation proliferates. Furthermore, the findings suggest that lung tissue in sarcoidosis creates an environment which promotes proliferation of monocytic cells. Pulmonary alveolar macrophages (AM) were originally recognized as phagocytosing scavenger cells (Ham & Cormack 1979), but presently they are also known to initiate and regulate inflammatory and immunological processes in several lung diseases (Herscowitz 1985, Unanue & Allen 1987, Sibille & Reynolds 1990). AM are thought to represent more mature cells of the mononuclear phagocyte system, and to be derived from peripheral blood monocytes (PBM) (Van Furth 1982, Ginsel 1993). As AM are continuously lost (mainly through a transport from the peripheral airways, via the trachea to the pharynx), the local AM population must be constantly replenished.(ABSTRACT TRUNCATED AT 400 WORDS)

Increased Number of Alveolar Macrophages Expressing Surface Molecules of the CD11/CD18 Family in Sarcoidosis and Idiopathic Pulmonary Fibrosis Is Related to the Production of Superoxide Anions by These Cells

This study was designed to investigate the expression and functional properties of leukocyte adhesion molecules (LeuCAM; CD11/CD18 family) on human alveolar macrophages (AM) from patients with sarcoidosis and idiopathic pulmonary fibrosis. Cells were obtained by bronchoalveolar lavage (BAL) from 17 patients with sarcoidosis (SA), 15 with idiopathic pulmonary fibrosis (IPF), and 14 nonsmokers (NS). Expression of LeuCAM on freshly isolated cells was studied using the peroxidase-antiperoxidase method with monoclonal antibodies (MoAb) detecting CD11a, CD11b, CD11c, and CD18. The functional properties of the adhesion molecules were studied by measuring superoxide anion production (O2-) of SA and IPF AM after blocking the CD18 molecule by an MoAb. Compared with nonsmokers, the samples from SA and IPF patients contained an increased number of AM expressing CD11a, CD11b, CD11c, and CD18 (all p < 0.008), which was correlated to the number of AM/ml BAL (p < 0.008). Spontaneous O2- secretion of AM was higher in SA (6.4 +/- 1.2 nMO2-/10(6) AM/120 min) and IPF (12.0 +/- 1.1 nMO2-/10(6) AM/120 min) compared with NS (2.5 +/- 0.2 nMO2-/10(6) AM/120 min) (both p < 0.008). Incubation of the AM with the MoAb anti-CD18 reduced the spontaneous O2- release from SA AM by 52 +/- 8% and from IPF AM by 49 +/- 3% but did not influence O2- release from NS AM (92 +/- 4%). Our data indicate that the increased expression of LeuCAM on AM in subjects with SA and IPF seems to be involved in the increased O2- production of these cells in both diseases.

Correlation of morphological patterns of nucleoli in alveolar macrophages with HLA-DR antigen expression in sarcoidosis.

Alveolar macrophages from patients with sarcoidosis express increased quantities of HLA-DR during activation. Because silver staining has been described as a sensitive indicator of cellular activity a study was performed to examine whether it relates to HLA-DR antigen expression. The relation between silver staining patterns of nucleoli and HLA-DR antigen expression was examined in alveolar macrophages collected by bronchoalveolar lavage from 11 patients with pulmonary sarcoidosis and 11 control subjects. The mean (SD) number of silver stained protein dots associated with the nucleolar organiser regions (AgNORs) was significantly higher in alveolar macrophages from patients with sarcoidosis (7.5 (1.5)) than in those from control subjects (5.6 (0.6)). The number of silver stained dots in alveolar macrophages correlated significantly with the intensity and the density of HLA-DR antigen expression in the patients with sarcoidosis. Silver staining may be a sensitive tool for the investigation of the biological cell activity of alveolar macrophages in sarcoidosis.

サルコイドーシスにおける単球, 肺胞マクロファージ上IL-2レセプター

サルコイドーシスにおける単球, 肺胞マクロファージ上IL-2レセプター