Gene/Protein Disease Symptom Drug Enzyme Compound
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Query: UNIPROT:P00750 (PLA)
 16,800 document(s) hit in 31,850,051 MEDLINE articles (0.00 seconds)

The balance between proteases and antiproteases in the lower respiratory tract is believed to play a role in the outcome of interstitial lung diseases. In this cross-sectional study, we measure several phagocyte derived enzymes, namely plasminogen activator, neutrophil elastase and an ill-defined protease active on the trialanine chromophore substrate succinyl-alanine3-nitroanilide (SLAPN) in bronchoalveolar lavage (BAL) fluid from 42 patients with pulmonary sarcoidosis and from 43 patients with collagen vascular disease (CVD), 22 without lung disease (group I) and 21 associated with parenchymal lung disease (group II). The results show: a) that sarcoidosis is associated with increased plasminogen activator activity and with the presence of enzymatic activity against SLAPN corresponding at least in part to a metalloprotease; b) that CVD in the absence of radiographic lung disease is associated with an increase of plasminogen activator activity and increased levels of alpha 1-antiprotease-neutrophil elastase complexes; c) that the majority of untreated CVD (group II) patients have detectable levels of neutrophil elastase activity. These data show that patients with pulmonary sarcoidosis and CVD have different enzymatic profiles in their lower respiratory tract as assessed by BAL. Thus, sarcoidosis (mostly lymphocytic) is associated with enhanced macrophage-derived proteolytic activity in BAL, while CVD patients both with and without lung disease have increased neutrophil counts and neutrophil elastase complexed to alpha 1-protease inhibitor and presumably inactive in BAL. Finally, only BAL from untreated CVD patients with interstitial lung disease contain neutrophil elastase activity. This latter activity could contribute to the lung lesions frequently observed in these disorders.
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PMID:Phagocyte enzymes in bronchoalveolar lavage from patients with pulmonary sarcoidosis and collagen vascular disorders. 218 5

Increased production of the serum protease plasminogen activator is associated with tissue damage. The in vitro production of plasminogen activator by alveolar macrophages obtained by bronchoalveolar lavage was studied in 22 normal subjects and 28 patients with interstitial lung disease to determine whether plasminogen activator is produced by normal alveolar macrophages and whether this is increased in patients with interstitial lung disease. Plasminogen activator activity, measured with an iodine-125 labelled fibrin release assay, was found to be dependent on time, effector cell numbers, and plasminogen concentration. Plasminogen activator production by alveolar macrophages from 14 normal non-smokers and eight normal smokers was similar and the mean value was 0.78 (SEM 0.16) urokinase (UK) units x 10(-8)/cell/hour. Alveolar macrophages from the seven patients with cryptogenic fibrosing alveolitis and six patients with histiocytosis-X produced more plasminogen activator (1.89 (0.25) and 4.54 (1.3) x 10(-8) UK units/cell/hour respectively) than macrophages from normal subjects (p less than 0.05), whereas those from 15 patients with sarcoidosis did not (1.09 (0.2) x 10(-8) UK units/cell/hour). Exposure of normal alveolar macrophages to immune complexes enhanced plasminogen activator production to 2.07 (0.27) x 10(-8) UK units/cell/hour, whereas exposure to products of activated T cells and to purified gamma interferon reduced plasminogen activator production (to 0.38 (0.11) and 0.62 (0.11) x 10(-8) UK units/cell/hour respectively). These studies show that plasminogen activator is produced by normal human alveolar macrophages and that its production is increased in patients with cryptogenic fibrosing alveolitis and histiocytosis-X.
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PMID:Production of plasminogen activator by alveolar macrophages in normal subjects and patients with interstitial lung disease. 321 49

Fibrin deposition is prominent in the histopathologic features of chronic interstitial lung disease. Human alveolar macrophages can potentially modulate this process because normal macrophages synthesize and express the initial enzymes of both coagulation and fibrinolytic pathways. In the present study, we examined the cell-associated procoagulant activity of macrophages lavaged from patients with sarcoidosis (n = 14) or idiopathic pulmonary fibrosis (n = 13) and compared the enzyme activities with that of a group of normal volunteers (n = 16). Cells from sarcoid patients had a mean (+/- 1 SD) tissue factor activity of 1,491 +/- 2,160 units/5 X 10(5) cells, as compared with a mean of 480 units (range, 140 to 1,000 units) for normal control subjects. The same cells had a mean plasma Factor VII equivalent of 4.7 ng/10(6) cells, as compared with 0.81 ng/10(6) cells (range, 0.2 to 2.0 ng) for the normal control subjects. The enhanced activity correlated with disease activity as judged by radiographic stage: only patients with Stage II or Stage III disease had consistently elevated procoagulant activity. There was no correlation of procoagulant activity with the percentage of lymphocytes in the alveolar fluid. Cells from patients with idiopathic pulmonary fibrosis also had increased tissue factor (mean, 2,980 +/- 2,619 units) but less consistently elevated Factor VII. There was considerable variation in both procoagulant activity and cell differentials between lavage sites in 10 patients in whom 2 separate lobes were studied concurrently. In addition, we examined the plasminogen activator (PA) activities of lavaged cells and concentrated alveolar fluids.(ABSTRACT TRUNCATED AT 250 WORDS)
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PMID:Abnormalities in pathways of alveolar fibrin turnover among patients with interstitial lung disease. 395 52

Bronchoalveolar lavage fluids (BALF) from patients with hypersensitivity pneumonitis (HP; n = 35), idiopathic pulmonary fibrosis (IPF, n = 41) and sarcoidosis (SARC, n = 48) were investigated for alterations in the alveolar hemostatic balance. Healthy individuals (n = 21) served as Controls. Procoagulant activity (PCA), tissue factor (TF) activity and F VII activity were assessed by means of specific recalcification assays. The overall fibrinolytic activity (FA) was measured using the (125)I-labeled fibrin plate assay. Fibrinopeptide A (FP-A), D-Dimer, plasminogen activators (PA) of the urokinase (u-PA) or tissue type (t-PA), PA-inhibitor I (PAI-1) and alpha2-antiplasmin (alpha2-AP) were determined by ELISA technique. As compared to Controls, all groups with interstitial lung disease (ILD) displayed an increase in BALF PCA by approximately one order of magnitude, and this was ascribed to enhanced TF activity by >98%. Accordingly, F VII-activity was increased in all ILD groups, and elevated FP-A levels were noted. There was no significant difference in procoagulant activities between the different ILD entities, but the increase in TF was significantly correlated with deterioration of lung compliance. Overall fibrinolytic activity did not significantly differ between ILD entities and Controls, although some reduction in IPF subjects was observed. Nevertheless, changes in the profile of the different pro- and antifibrinolytic compounds were noted. U-PA, but not t-PA levels were significantly reduced in all ILD groups. alpha2-AP was markedly elevated throughout, whereas PAI-1 levels were lowered. As a balance of
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PMID:Enhanced tissue factor pathway activity and fibrin turnover in the alveolar compartment of patients with interstitial lung disease. 1089 38

Intraalveolar fibrin formation is a consistent finding in acute inflammatory and chronic interstitial lung disease. Polymerization of fibrin in the presence of pulmonary surfactant results in far-reaching incorporation of the hydrophobic surfactant compounds into the growing fibrin matrix, with loss of surface activity, altered fibrin structure and reduced susceptibility of the clot to fibrinolysis. For specific targeting of such alveolar fibrin, we designed a hybrid molecule consisting of the catalytic domain of urokinase (B-chain) and the hydrophobic surfactant protein B (SP-B), termed SPUC. The urokinase B-chain, obtained by limited reduction of human two-chain-urokinase (u-PA) and subsequent affinity purification, was chemically coupled to SP-B in a semi-organic solvent system using a hetero-bifunctional crosslinker. Purification of the chimeric proteins included reversed phase and cation exchange chromatography. SDS-PAGE and Western Blotting with immunostaining were employed for biochemical characterization of the conjugate. Chromogenic substrate assays, (125)I-based fibrin plate assays, active site titration and surface tension measurements (pulsating bubble surfactometer) were performed to analyze the specific fibrinolytic activity of the conjugate and its surface activity. SPUC was found i) to be assembled stoichiometrically in a 1: 1 fashion (SP-B: u-PA), ii) to fully retain the biophysical activity as compared to native SP-B and iii) to also retain the fibrinolytic activity. SPUC was 2-3 fold more effective in lysis of surfactant containing clots and 5-fold more resistant against plasminogen activator 1 (PAI-1) as compared to the native u-PA. We conclude that urokinase and SP-B can be chemically crosslinked, thereby yielding a fibrinolytic enzyme suitable for targeting alveolar fibrin.
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PMID:Chemical crosslinking of urokinase to pulmonary surfactant protein B for targeting alveolar fibrin. 1254 Sep 54