High levels of extracellular matrix metalloproteinase inducer are expressed in lymphangioleiomyomatosis.

Pulmonary lymphangioleiomyomatosis is pathologically characterized by the proliferation of abnormal smooth muscle-like cells (lymphangioleiomyomatosis cells) that synthesize excess matrix metalloproteinases. Extracellular matrix metalloproteinase inducer is minimally expressed in the healthy lung, but is up-regulated in various lung injuries that are apparently associated with matrix metalloproteinases. We therefore immunohistochemically stained extracellular matrix metalloproteinase inducer in lymphangioleiomyomatosis cells and measured extracellular matrix metalloproteinase inducer in bronchoalveolar lavage fluid using an enzyme-linked immunosorbent assay. We also quantified extracellular matrix metalloproteinase inducer messenger RNA expression in the lung using quantitative reverse transcriptase-polymerase chain reaction. Intense staining for extracellular matrix metalloproteinase inducer in lymphangioleiomyomatosis cells indicated high immunoreactivity. Dual immunofluorescence studies revealed diffuse colocalization between extracellular matrix metalloproteinase inducer and alpha smooth muscle actin, matrix metalloproteinase-2, or matrix metalloproteinase-9. Although levels of extracellular matrix metalloproteinase inducer messenger RNA did not differ in whole lung homogenates from patients with lymphangioleiomyomatosis and healthy controls (1.7 +/- 0.1 versus 1.5 +/- 0.2 SE, not significant; both n = 4), lymphangioleiomyomatosis nodules retrieved by laser capture microdissection expressed 5.1 (+/-1.0 SE)-fold higher levels of extracellular matrix metalloproteinase inducer messenger RNA than lung homogenates (P = .0077, n = 4). Levels of extracellular matrix metalloproteinase inducer were significantly elevated in bronchoalveolar lavage fluid from lymphangioleiomyomatosis patients compared with controls (82.7 +/- 19.5 versus 38.6 +/- 9.0 SE pg/mL, P = .0497; n = 8 and 9, respectively). Increased levels of extracellular matrix metalloproteinase inducer colocalized with increased matrix metalloproteinases in lymphangioleiomyomatosis cells indicate that it potentially functions in pulmonary lymphangioleiomyomatosis.

Interleukin-1beta and tumor necrosis factor-alpha have opposite effects on fibroblasts and epithelial cells during basement membrane formation.

Interleukin-1beta (IL-1beta) and tumor necrosis factor-alpha (TNF-alpha) are typical proinflammatory cytokines that influence various cellular functions, including metabolism of the extracellular matrix. We examined the roles of IL-1beta and TNF-alpha in basement membrane formation in an in vitro model of alveolar epithelial tissue composed of alveolar epithelial cells and pulmonary fibroblasts. Formation of the basement membrane by immortalized rat alveolar type II epithelial (SV40-T2) cells, which ordinarily do not form a continuous basement membrane, was dose-dependently upregulated in the presence of 2 ng/ml IL-1beta or 5 ng/ml TNF-alpha. IL-1beta or TNF-alpha alone induced increased secretion of type IV collagen, laminin-1, and nidogen-1/entactin, all of which contributed to this upregulation. In contrast, while SV40-T2 cells cultured with a fibroblasts-embedded type I collagen gel were able to form a continuous basement membrane, they failed to form a continuous basement membrane in the presence of IL-1beta or TNF-alpha. Fibroblasts treated with IL-1beta or TNF-alpha secreted matrix metalloproteinase (MMP)-9 and MMP-2, and these MMPs inhibited basement membrane formation and degraded the basement membrane architecture. Neither IL-1beta- nor TNF-alpha-treated SV40-T2 cells increased the secretion of MMP-9 and MMP-2. These results suggest that IL-1beta participates in basement membrane formation in two ways. One is the induction of MMP-2 and MMP-9 secretion by fibroblasts, which inhibits basement membrane formation, and the other is induction of basement membrane component secretion from alveolar epithelial cells to enhance basement membrane formation.

Role of basement membrane in EMMPRIN/CD147 induction in rat tracheal epithelial cells.

Extracellular matrix metalloproteinase inducer (EMMPRIN) is a glycosylated transmembrane protein known to induce matrix metalloproteinases (MMPs). Although the expression of EMMPRIN is physiologically limited to fetal lung epithelium, the transcriptional regulation of this protein remains to be elucidated. We hypothesized that the interaction of epithelial cells with the basement membrane regulates EMMPRIN expression. The basement membrane has highly integrated architecture composed of specific extracellular matrix, such as laminins and type IV collagen, and exhibits multiple functions. We previously developed a structured basement membrane mimic, a synthesized basement membrane (sBM) substratum, in which laminin-111, a unique component of embryonic lungs, is incorporated. In the present study we quantified expression of EMMPRIN mRNA of rat tracheal epithelial cells cultured on sBM, laminin-111, type IV collagen, or laminin-332. EMMPRIN was upregulated on sBM and laminin-111, although this was not accompanied by MMP-9 induction. In contrast, type IV collagen and laminin-332 did not induce EMMPRIN. These findings suggest potential roles for basement membrane in the transcriptional regulation of tracheal epithelial EMMPRIN.

Differentiation of tracheal basal cells to ciliated cells and tissue reconstruction on the synthesized basement membrane substratum in vitro.

Although lung epithelial cells directly attach to the basement membrane underneath in vivo, harvested epithelial cells are typically cultured on type I collagen gel (Col I-gel) in vitro. Recently we developed new culture substratum, designated as "synthesized Basement Membrane" (sBM), that has bared lamina densa on fibrillar collagen. To validate the usefulness of sBM substratum in airway tissue reconstitution in vitro, we cultured rat tracheal epithelial cells on sBM substratum and Col I-gel. When starting the air-liquid interface culture, most of the epithelial cells were squamous and positive for the basal cell marker cytokeratin 14 (CK14). After 14 days on sBM substratum, CK14-positive cells differentiated not only to Clara and mucous cells, but also to ciliated cells. Those differentiated cells formed pseudostratified-like epithelium and the remaining CK14-positive cells were polarized to the basal side. However, on Col I-gel, the CK14-positive cells were still squamous and not polarized, and ciliated cells did not appear. In conclusion, we established a new culture model on sBM substratum in which basal cells could differentiate to ciliated cells. The application of sBM substratum is useful in the study of the airway epithelial cell differentiation in vitro.

[Case of drug-induced pneumonia followed by sequential bronchoalveolar lavage].

A 30-year-old woman who had been receiving minocycline for 11 days to treat a skin burn presented with high fever and progressive dyspnea. Chest radiography demonstrated bilateral pulmonary infiltrates with ground glass opacities. She was admitted to our hospital under a tentative diagnosis of minocycline-induced pneumonia. Minocycline therapy was discontinued at hospital admission, which led to dramatic clinical and radiographic improvement. Bronchoalveolar lavage fluid (BALF) analysis three days after the onset of the pneumonia showed increased numbers of total cells (7.68 x 10(5)/ml), neutrophils (33%) and eosinophils (14%). An increased number of peripheral blood neutrophils was also noted at the time of hospital admission. Follow-up evaluations of BALF 10 days and 34 days after the onset showed rapidly declining numbers of neutrophils and eosinophils. We also measured the levels of several cytokines in BALF, suggesting that TNF-alpha and IL-8 contributed to the accumulation of neutrophils, whereas IL-5 contributed to the accumulation of eosinophils. In summary, we report here the temporal change in the inflammatory cell and cytokine profile in BALF, serum, or both, in a case of drug-induced pneumonia.

[Studies on airway hyperresponsiveness by the Astograph(r) method in asthmatics and young adult non-asthmatic asymptomatics].

We investigated airway hyperresponsiveness (AHR) by the continuous inhalation method using an Astograph(R) in 105 asthmatics and 141 non-asthmatic asymptomatics. The range of Dmin (1 U=one minute inhalation of 1 mg/ml of methacholine) of asthmatics was 0.001 to 28.70 U, and that of adjusted Dmin of non-asthmatic asymptomatics was 0.28 to 190 U; thus, an apparent overlap was recognized in the distributions of Dmin. Ninety-five percent of asthmatics had a Dmin lower than 7 U, and 95% of non-asthmatic asymptomatics had a Dmin higher than 0.9 U. Presuming that almost all asthmatics had AHR, it was inferred that nearly half of non-asthmatic asymptomatics had AHR, too. Comparison with previous reports suggests that AHR in healthy people may be increasing generally. When Dmin is determined to be>7 U by the Astograph(R) method, it is likely that the patient does not have asthma. When a patient has a Dmin<0.9 U, it is highly probable that the patient has asthma.

Effect of low-dose theophylline on airway inflammation in COPD.

OBJECTIVE: Recent studies have shown that theophylline may exert anti-inflammatory effects on neutrophils. We undertook to assess the effect of theophylline on airway inflammation in COPD. METHODOLOGY: We performed a 4-week randomized double-blind, placebo-controlled study in 11 theophylline-naive patients with mild to moderate COPD. After a 1-week run-in period, six subjects were administered 400 mg/day theophylline (Theodur; Nikken Chemicals Co. Ltd, Tokyo, Japan) for 4 weeks, while five subjects were administered a placebo. Induced sputum was obtained before and after the run-in period and then after 2 and 4 weeks of treatment. Cell differential count and levels of interleukin-8, matrix metalloproteinase-9, neutrophil elastase (NE), myeloperoxidase (MPO), alpha1-antitrypsin (alpha1-AT), leukotriene B4 and tissue inhibitor of metalloproteinases-1 (TIMP-1) were assessed. RESULTS: No variable was significantly different during the run-in period or with placebo treatment. In contrast, theophylline treatment significantly decreased NE and MPO levels at 4 weeks, although the cell differential count did not change appreciably as a result of treatment. CONCLUSION: These results suggest that 4 weeks of theophylline treatment attenuates neutrophil-associated inflammation in the airways of mild to moderate COPD patients. However, the clinical benefits remain to be determined.

A case of idiopathic pulmonary alveolar proteinosis accompanied by T-cell receptor gene rearrangement in bronchoalveolar lavage fluid cells.

We describe a case of a patient with idiopathic pulmonary alveolar proteinosis (PAP), who had an elevated serum level of antigranulocyte-macrophage colony stimulating factor (anti-GM-CSF) antibody accompanied by T-cell receptor gene rearrangements in BAL fluid cells. Histopathological examination of the lung excluded lymphoma but revealed PAP and silicosis. There was no detectable serum anti-GM-CSF antibody in 50 outpatients with advanced silicosis who did not have PAP, suggesting that anti-GM-CSF antibody is directly linked to PAP but not to silicosis. We speculate that monoclonal expansion of a T-cell population may play a role in the production of anti-GM-CSF antibody and the development of PAP.