scholarly journals Elastase secretion by peritoneal exudative and alveolar macrophages.

1977 ◽  
Vol 146 (3) ◽  
pp. 802-808 ◽  
Author(s):  
R White ◽  
H S Lin ◽  
C Kuhn

Mouse alveolar macrophages (AM) cultured in the absence of serum secrete an elastolytic enzyme. The elastase from AM resembles the previously described elastase from peritoneal macrophages (PM) in pH optimum and inhibition profile. The macrophage enzymes do not appear to be stored, and with periodic changes in the culture medium, accumulate extracellularly for up to 10 days. Resident PM produce barely detectable levels of extracellular elastase unless given a phagocytic load. Thioglycollate-stimulated peritoneal exudative macrophages (PEM), however, secret easily detectable levels of elastase, which can be further increased with a phagocytic load. Without any additional stimulation, AM secret an elastolytic activity comparable to that of the PEM receiving a phagocytic load, but unlike PM they do not increase elastase secretion after phagocytosis.

1987 ◽  
Author(s):  
S Menasni ◽  
W Hornebeck ◽  
L Robert ◽  
Y Legrand

Elastin degrading enzymes have been reported in the vessel wall and both fibroblasts and smooth muscle cells have been shown to produce elastase type enzymes in culture. Data is presented here showing that porcine aortic endothelial cells produce enzyme activities hydrolyzing elastin and synthetic substrates I Sue Ala Ala Ala nitroanilide, SAPNAI considered specific for elastase. Enzyme activity against the SAPNA but not against H-elastin was found to be associated with the cells after triton lysis .This activity was not secreted into the culture medium . The elastolytic activity has been partially characterized in relation to the kinetic of hydrolysis, pH optimum and susceptibility to different inhibitors. These studies revealed the presence of at least two enzymes: a metalo-protease with a pH optimum of 7.5 which accounts for approx. 80% of the total activity, and a serine protease with pH optimum of 8.0 which accounts for the remaining 20% . When the conditioned culture medium was studied, virtually no proteolytic activity could be detected even after activation with an organomercurial agent. However fractionation of the culture medium by gel filtration on HPLC resulted in elastolytic activity both against H-elastin and SAPNA. Proteolytic activity against casein could also be revealed after separation on SDS-PAGE. It is likely that these separation techniques remove an inhibitor also produced by the endothelial cells and allow the expression of proteolytic activity. That the elastolytic activity and the caseinolytic activity revealed by HPLC and PAGE respectively represent the activity of the same enzyme hase not yet been determined, and its relationship to the Stromelysin described by Herron et al(J. Biol. Chem. , 1986, 261. 2810-2813) in rabbit brain capillary endothelial cells is being investigated.


1981 ◽  
Vol 197 (2) ◽  
pp. 523-526 ◽  
Author(s):  
Paul D. Wightman ◽  
Mary Ellen Dahlgren ◽  
James C. Hall ◽  
Philip Davies ◽  
Robert J. Bonney

Resident mouse peritoneal macrophages contain a phospholipase C of high activity that is specific for phosphatidylinositol. The activity has a neutral pH optimum, is Ca2+-dependent and has a maximum reaction velocity of 525nmol/h per mg of protein. Certain phenothiazines are potent inhibitors of this activity.


1995 ◽  
Vol 41 (13) ◽  
pp. 192-199 ◽  
Author(s):  
Christian Korherr ◽  
Michael Roth ◽  
Eggehard Holler

A 68-kDa extracellular glycoprotein from Physarum polycephalum that hydrolyses specifically poly(β-L-malic acid) by removing monomers of L-malic acid in an exolytic manner has been purified and characterized. The enzyme was purified 1740-fold from the culture medium by ammonium sulfate precipitation, hydrophobic interaction chromatography on butyl-Toyopearl, and gel permeation chromatography on Superdex 200 to a specific activity of 9.0 μmol∙min−1∙mg−1. The hydrolase was also purified from the cytosol, which contained 1 mg in 43 g cells in contrast to 1 mg extracellular enzyme in 28 L of culture medium. The pH optimum was pH 3.5 as a result of the effect of an acidic side chain on Vmax and the preferred binding of poly(β-L-malate) in the ionized form. Intracellular hydrolase was only marginally active on [14C]poly(β-L-malate) that had been injected into plasmodia. Poly(L-aspartate), poly(L-glutamate), poly(vinyl sulfate), and poly(acrylate) were neither bound nor degraded by the hydrolase. Poly(β-hydroxybutyric acid), which was considered the reduced form of poly(β-L-malate), was not a substrate. The enzyme is neither a metallo- nor a serine-esterase, and is distinct from poly(3-hydroxybutyric acid) depolymerases. It is related to a glucosidase with respect to hydrophobic interaction chromatography, the pH-activity dependence, and its inhibition with mercuribenzoate, N-bromosuccinimide, and D-gluconolactone, but not the use of the substrates.Key words: poly(β-L-malate), polymalatase, Physarum polycephalum, biodegradative polymer.


1981 ◽  
Vol 193 (2) ◽  
pp. 589-605 ◽  
Author(s):  
M J Banda ◽  
Z Werb

Macrophage elastase was purified from tissue-culture medium conditioned by inflammatory mouse peritoneal macrophages. Characterized as a secreted neutral metalloproteinase, this enzyme was shown to be catalytically and immunochemically distinct from the mouse pancreatic and mouse granulocyte elastases, both of which are serine proteinases. Inhibition profiles, production of nascent N-terminal leucine residues and sodium dodecyl sulphate/polyacrylamide-gel electrophoresis of degraded elastin indicated that macrophage elastase is an endopeptidase, with properties of a metalloproteinase, rather than a serine proteinase. Macrophage elastase was inhibited by alpha 2-macroglobulin, but not by alpha 1-proteinase inhibitor. Macrophage elastase was resolved into three chromatographically distinct forms. The predominant form had mol.wt. 22 000 and was purified 4100-fold. Purification of biosynthetically radiolabelled elastase indicated that this form represented less than 0.5% of the secreted protein of macrophages. Approx. 800% of the starting activity was recovered after purification. Evidence was obtained for an excess of an endogenous inhibitor masking more than 80% of the secreted activity.


1996 ◽  
Vol 270 (3) ◽  
pp. L429-L434 ◽  
Author(s):  
P. Goldbach ◽  
S. Dumont ◽  
R. Kessler ◽  
P. Poindron ◽  
A. Stamm

Interferon-gamma (IFN-gamma) was entrapped with an efficiency of 30-40% in muramyl tripeptide-containing liposomes by a freeze-thawing procedure. A microcytotoxicity assay was developed to measure the tumoricidal activity of mouse alveolar macrophages (AM) against tumoral target cells with a colorimetric viability test. Free IFN-gamma and liposomal muramyl tripeptide phosphatidylethanolamine (MTP-PE) were found to be only slightly effective to activate in vitro AM, whereas encapsulation of both INF-gamma and MTP-PE within the same liposomes produced higher activation of AM. Aerosolized IFN-gamma and liposomal immunomodulators enhanced antitumor properties of AM recovered in mice 24 h postinhalation. Whereas free IFN-gamma also induced a substantial activation of peritoneal macrophages, liposomal encapsulation significantly reduced the systemic activity of inhaled immunomodulators. This approach provides a useful model for the compartmentalized organ-specific activation of AM in mice.


1968 ◽  
Vol 128 (5) ◽  
pp. 1031-1048 ◽  
Author(s):  
S. G. Axline

The acid phosphatase activity of normal alveolar and BCG-induced alveolar macrophages has been examined. Five electrophoretically distinct forms of acid phosphatase have been identified in both normal and BCG-induced macrophages. The acid phosphatases can be divided into two major categories. One category, containing four distinct forms, is readily solubilized after repeated freezing and thawing or mechanical disruption The second category, containing one form, is firmly bound to the lysosomal membrane and can be solubilized by treatment of the lysosomal fraction with Triton X-100. The Triton-extractable acid phosphatase and the predominant aqueous soluble acid phosphatase have been shown to differ in the degree of membrane binding, in solubility, in net charge, and in molecular weight. The two pre-dominant phosphatases possess identical pH optimum and do not differ in response to enzyme inhibitors. BCG stimulation has been shown to result in a nearly twofold increase in acid phosphatase activity. A nearly proportionate increase in the major acid phosphatase forms has been observed.


1997 ◽  
Vol 3 (S2) ◽  
pp. 11-12
Author(s):  
H. J. Muenchen ◽  
S.K. Aggarwal ◽  
H.K. Misra ◽  
P. J. Andrulis

Poly-[(trans-1,2-diaminocyclohexane) platinumj-carboxyamylose (“poly-plat”), 5-sulfosalicylato-trans -(1,2-diaminocyclohexane) platinum (SSP), and 4-hydroxy-∝-sulfonylphenylacetato (trans 1,2-diaminocyclohexane) platinum (II) (SAP) are second generation analogs of cisplatin (CDDP) with higher efficacy and potency than cisplatin. This is particularly true of “poly-plat” which contains 1/5 the platinum of CDDP. In order to understand the mechanism of action of these compounds, isolated murine peritoneal macrophages in culture medium were treated with “poly-plat”, SSP, or SAP (5 μg/ml) for 2 h. Drug containing medium was then replaced with fresh medium and the cells were allowed to incubate at 37° C (5% CO2) for 24 h. Supernatants were collected at 0.5, 1, 2, and 24 h post-treatment for immunocytochemical analysis. Confocal microscopy studies demonstrated an increase in the number of lysosomes in the treated macrophages, but only “poly-plat” and SSP treated macrophages were stimulated to form cytoplasmic extensions at 2 h and 24 h.


1980 ◽  
Vol 152 (5) ◽  
pp. 1236-1247 ◽  
Author(s):  
C A Rouzer ◽  
W A Scott ◽  
A L Hamill ◽  
Z A Cohn

A method for the radiochemical assay of LTC production by mouse peritoneal macrophages in vitro is presented. The method involves labeling macrophages in culture with [5,6,8,9,11,12,14,15-3H]20:4 followed by stimulation of arachidonic acid (20:4) release under the experimental conditions desired. Radiolabeled leukotriene C (LTC) is recovered from the culture medium by extraction and silicic acid chromatography in 40% yield with full retention of biological activity. Because this LTC is radiochemically pure, the quantity of LTC release may be estimated from the amount of radioactivity in the sample. Use of the radioassay to study parameters affecting LTC synthesis by macrophages indicated that the time course of LTC synthesis and its relationship to the dose of a phagocytic stimulus (zymosan) were very similar to those of prostaglandin (PG) release. LTC release was also similar to that of PG in that lower levels of both metabolites were produced by Corynebacterium parvum-elicited macrophages than by resident cells. Finally, LTC release was stimulated in response to a challenge with antigen-antibody complexes, but lower maximal levels were attained than those with zymosan. The data presented here are consistent with the hypothesis that challenge of macrophages with a phagocytic stimulus leads to the release of 20:4 by an inducible phospholipase. Cyclooxygenase and lipoxygenase then compete for the released 20:4, leading to the production of PG, hydroxyeicosatetraenoic acids, and LTC.


1978 ◽  
Vol 169 (2) ◽  
pp. 265-276 ◽  
Author(s):  
David E. Woolley ◽  
Robert W. Glanville ◽  
Dennis R. Roberts ◽  
John M. Evanson

1. The neutral collagenase released into the culture medium by explants of human skin tissue was purified by ultrafiltration and column chromatography. The final enzyme preparation had a specific activity against thermally reconstituted collagen fibrils of 32μg of collagen degraded/min per mg of enzyme protein, representing a 266-fold increase over that of the culture medium. Electrophoresis in polyacrylamide disc gels showed it to migrate as a single protein band from which enzyme activity could be eluted. Chromatographic and polyacrylamide-gel-elution experiments provided no evidence for the existence of more than one active collagenase. 2. The molecular weight of the enzyme estimated from gel filtration and sodium dodecyl sulphate/polyacrylamide-gel electrophoresis was approx. 60000. The purified collagenase, having a pH optimum of 7.5–8.5, did not hydrolyse the synthetic collagen peptide 4-phenylazobenzyloxycarbonyl-Pro-Leu-Gly-Pro-d-Arg-OH and had no non-specific proteinase activity when examined against non-collagenous proteins. 3. It attacked undenatured collagen in solution at 25°C, producing the two characteristic products TCA(¾) and TCB(¼). Collagen types I, II and III were all cleaved in a similar manner by the enzyme at 25°C, but under similar conditions basement-membrane collagen appeared not to be susceptible to collagenase attack. At 37°C the enzyme attacked gelatin, producing initially three-quarter and one-quarter fragments of the α-chains, which were degraded further at a lower rate. As judged by the release of soluble hydroxyproline peptides and electron microscopy, the purified enzyme degraded insoluble collagen derived from human skin at 37°C, but at a rate much lower than that for reconstituted collagen fibrils. 4. Inhibition of the skin collagenase was obtained with EDTA, 1,10-phenanthroline, cysteine, dithiothreitol and sodium aurothiomaleate. Cartilage proteoglycans did not inhibit the enzyme. The serum proteins α2-macroglobulin and β1-anti-collagenase both inhibited the enzyme, but α1-anti-trypsin did not. 5. The physicochemical and enzymic properties of the skin enzyme are discussed in relation to those of other human collagenases.


1999 ◽  
Vol 62 (5) ◽  
pp. 543-546 ◽  
Author(s):  
J. FERNÁNDEZ ◽  
A. F. MOHEDANO ◽  
P. GAYA ◽  
M. MEDINA ◽  
M. NUÑEZ

Three proteinases were isolated from culture medium of Pseudomonas fluorescens INIA 745 and purified to homogeneity by a combination of Phenyl-Sepharose, DEAE-Sepharose, and Sephadex G-100 chromatography. Optimal temperature for enzymatic activity was 45°C for all three proteinases. The pH optimum of proteinases I and II was found to be 7.0, while that of proteinase III was 8.0. Divalent metal ions like Cu2+, Co2+, Zn2+, Fe2+, and Hg2+ were inhibitory to proteinase activity while Ca2+, Mg2+, and Mn2+ had little or no inhibitory effect. The three enzymes were strongly inhibited by EDTA and 1,10-phenantroline and partially by cysteine. The three enzymes are metalloproteinases since they were inhibited by chelators and reactivated by Co2+, Mn2+, Cu2+, and Zn2+. The Km values of proteinases I, II, and III for casein were calculated to be 3.2, 2.6, and 5.2 mg/ml, respectively. Proteinases II and III rapidly degraded β-casein, with preference to αs1-casein, whereas proteinase I hydrolyzed both casein fractions at a slow rate.


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