The Induction of Lysosomal Enzyme Release from Leucocytes of Normal and Emphysematous Subjects and the Effects of Tobacco Smoke upon Phagocytosis

1980 ◽  
Vol 58 (5) ◽  
pp. 403-409 ◽  
Author(s):  
D. C. S. Hutchison ◽  
R. Desai ◽  
D. Bellamy ◽  
H. Baum

1. The lysosomal enzymes of circulating polymorphonuclear leucocytes contain a potent elastase; release of this enzyme within the lung is thought to be responsible for the destruction of elastic tissue in pulmonary emphysema. 2. The release of lysosomal enzymes from blood leucocytes of normal and emphysematous subjects during phagocytosis of particulate material was studied In vitro. Acid phosphatase and acid ribonuclease were used as markers of lysosomal enzyme release, no sufficiently sensitive assay for elastase being available. Cigarette smoke was separated into ‘particulate’ and ‘soluble’ fractions. In a preliminary study, the particulate fraction stimulated enzyme release; in the experiments reported here, latex particles were used to produce this effect. 3. Approximately one-third of the total lysosomal enzyme content was released to the exterior of the cell during phagocytosis of latex particles. In this respect there was no difference between normal and emphysematous subjects. 4. The effects of the non-particulate soluble fraction of cigarette smoke on phagocytosis-induced enzyme release were studied. This fraction inhibited enzyme release from polymorphonuclear leucocytes of normal subjects but not from those of emphysematous patients. When the ‘cigarette-smoke solution’ was replaced by the respiratory inhibitor, antimycin A, a similar inhibition of enzyme release occurred. The inhibition of phagocytosis in cells of normal subjects is presumed to be due to a respiratory inhibitor such as carbon monoxide in the soluble fraction of the smoke. We postulate that the polymorphonuclear leucocytes of emphysematous patients are adapted to hypoxic conditions so that inhibition of enzyme release does not occur.

1968 ◽  
Vol 46 (3) ◽  
pp. 499-502 ◽  
Author(s):  
B. M. Hegdekar

Female rats of the Long-Evans hooded strain, 4–6 months old and weighing 275–300 grams, were subjected to unilateral nephrectomy and the acid phosphatase activity in the remaining kidney was studied at the end of 24, 48, 72 hours, and 8 days respectively. Most of the acid phosphatase was found in the particulate fraction in normal kidneys. The enzyme activity in the soluble fraction was found to have increased the second day after the operation, but decreased to the original level by the end of 72 hours. The free activity of the lysosomal fraction also increased by the end of second postoperative day. A change in the permeability of the lysosomal membrane before the enzyme release was observed. The probable role of lysosomal enzymes in the initiation of mitotic divisions during compensatory renal hyperplasia is discussed.


1974 ◽  
Vol 139 (6) ◽  
pp. 1395-1414 ◽  
Author(s):  
L. J. Ignarro ◽  
T. F. Lint ◽  
W. J. George

The purpose of this investigation was to examine the effects of autonomic neurohormones, cyclic nucleotides, and related agents on the immunologic discharge of lysosomal enzymes from, and phagocytosis by, purified human neutrophils. In order to discern the possible intracellular mechanisms by which certain neurohormones influence neutrophil function, the concentrations of cyclic AMP and cyclic GMP in neutrophils were assessed during cell contact with phagocytizable particles and autonomic agents. The model system employed for study was the interaction of purified human neutrophils with rheumatoid arthritic (RA) serum-treated zymosan particles at 37°C in a neutral, balanced salt solution containing glucose. Neutrophils ingested the particles and discharged ß-glucuronidase but not lactate dehydrogenase activity during 30 min of incubation. Treatment of zymosan particles with RA serum was more effective than treatment with normal serum with regard to the extent of both particle uptake and lysosomal enzyme release. During contact of neutrophils with RA serum-treated zymosan particles epinephrine, isoproterenol, and cyclic AMP inhibited both particle ingestion and ß-glucuronidase discharge. These actions of epinephrine were associated with a concomitant elevation of cyclic AMP levels. In contrast to the actions of catecholamines and cyclic AMP, acetylcholine and cyclic GMP accelerated lysosomal enzyme release without affecting particle uptake. The actions of acetylcholine were associated with a concomitant elevation of cyclic GMP levels. Increases in neutrophil levels of cyclic GMP but not of cyclic AMP were associated also with the discharge of ß-glucuronidase provoked by particles in the absence of added cholinergic agents. The data suggest that the immunologic release of lysosomal enzymes from human neutrophils can be regulated by autonomic neurohormones, perhaps via the selective formation of appropriate nucleotides.


1973 ◽  
Vol 58 (1) ◽  
pp. 27-41 ◽  
Author(s):  
Robert B. Zurier ◽  
Sylvia Hoffstein ◽  
Gerald Weissmann

In order to study mechanisms underlying selective enzyme release from human leukocytes during phagocytosis, the effects were studied of compounds which affect microtubule integrity or the accumulation of cyclic nucleotides. Human leukocytes selectively extrude lysosomal enzymes (ß-glucuronidase) from viable cells during phagocytosis of zymosan or immune complexes, or upon encounter with immune complexes dispersed along a non-phagocytosable surface such as a millipore filter. In each circumstance, lysosomal enzyme release was reduced by previous treatment of cells with pharmacological doses of drugs which disrupt microtubules (e.g. 10-3–10-5 M colchicine) or with agents which affect accumulation of adenosine 3'5'-monophosphate (cAMP) (e.g. 10-3 M cyclic nucleotides and 2.8 x 10-4–2.8 x 10-6 M prostaglandin E (PGE) and A (PGA) compounds). Preincubation of cells with 5 µg/ml cytochalasin B resulted in complete inhibition of zymosan ingestion, but not of adherence of zymosan particles to plasma membranes or selective enzyme release. In this system, in which enzyme release was independent of particle uptake, preincubation of cells with colchicine, vinblastine, dibutyryl cAMP, or PGE1 also reduced extrusion of lysosomal enzymes. When cell suspensions were incubated with membrane-lytic crystals of monosodium urate (MSU), cytoplasmic as well as lysosomal enzymes were released with subsequent death of the cells. However, enzyme release followed phagocytosis of crystals (as measured by enhanced C-1 oxidation of glucose) and was due to "perforation from within" of the lysosomal membrane, rather than lysis by crystals of the plasma membrane. Enzyme release after MSU ingestion was also reduced when cells were treated with pharmacological doses of the test agents. When cells were killed by Triton X-100, acting on the plasma membrane, C-1 oxidation of glucose was abolished and enzyme release could not be inhibited pharmacologically. These observations suggest that lysosomal enzyme release from human phagocytes can be an active process which accompanies plasma membrane stimulation, is independent of cell death, and may be controlled by cyclic nucleotides and agents which affect microtubules.


1980 ◽  
Vol 44 (1) ◽  
pp. 299-315
Author(s):  
R.M. McMillan ◽  
D.E. Macintyre ◽  
J.E. Beesley ◽  
J.L. Gordon

We have investigated the role in macrophage lysosomal enzyme release of arachidonate metabolites, extracellular divalent cations and cyclic AMP (cAMP) which modulate secretion in other cell types. Lysosomal enzyme secretion induced by zymosan was accompanied by release of malondialdehyde (MDA), which is derived from arachidonic acid via prostaglandin synthase. Blockade of MDA formation, by aspirin or indomethacin, was associated with only a small inhibitory effect on lysosomal enzyme release by zymosan: arachidonate metabolites thus play only a minor role in mediating macrophage lysosomal enzyme release. Zymosan-induced secretion of lysosomal enzymes from macrophages did not require extracellular magnesium or calcium although release was enhanced by magnesium and inhibited by calcium. These effects may be related to an influence of the ions on phagocytosis. Elevation of intracellular divalent cation concentrations, by ionophore A23187, induced release of lysosomal enzymes but this was a result of cell lysis. Adenylate cyclase stimulants and dibutyryl cAMP produced slight inhibition of zymosan-induced lysosomal enzyme release. Aminophylline and papaverine caused more marked inhibition but their effects may be due to actions independent of phosphodiesterase inhibition. Our data indicate that arachidonate metabolites and cAMP do not play a major role in regulating zymosan-induced enzyme release from macrophages. Extracellular calcium and magnesium may modulate secretion but the role of intracellular divalent cations remains to be established. We conclude that macrophage lysosomal enzyme secretion is controlled by regulatory mechanisms different from those which control similar degranulation processes in other cell types.


1988 ◽  
Vol 90 (1) ◽  
pp. 167-171
Author(s):  
A. TIEDTKE ◽  
L. RASMUSSEN ◽  
J. FLORIN-CHRISTENSEN ◽  
M. FLORIN-CHRISTENSEN

The ciliate Tetrahymena thermophila releases lysosomal enzymes into nutrient and starvation media. We show here that this process occurs selectively, i.e. without leakage of cytoplasmic components, as indicated by lack of release of isocitrate dehydrogenase, a cytosolic enzyme with high activity in Tetrahymena. The role of intracellular Ca2+ in the process was also investigated. The Ca2+ ionophore A23187 has strong stimulatory effects on this release. Ionophore stimulation is maximal in the presence of extracellular Ca2+ but can occur also in its absence. Quin 2 fluorescence measurements indicate that intracellular Ca2+ increases in both cases. Mg2+ completely prevents the stimulatory effects of A23187. Ionomycin, another Ca2+ ionophore, also stimulates lysosomal enzyme release with a maximal response in the presence of extracellular Ca2+. Measurements of extracellular isocitrate dehydrogenase showed that ionophore-stimulated lysosomal enzyme release can take place without leakage of cytoplasmic components. The observations that divalent cation ionophores stimulate selective lysosomal enzyme release and that this effect is strongest in the presence of external Ca2+ indicate that this cation plays a crucial role in the control of this process in Tetrahymena. Together with other observations they support the view that a subpopulation of Tetrahymena lysosomes has properties like those of secretory vesicles.


1979 ◽  
Vol 184 (2) ◽  
pp. 345-354 ◽  
Author(s):  
Wei Hsueh ◽  
Charles Kuhn ◽  
Philip Needleman

The phospholipids of rabbit alveolar macrophages were pulse-labelled with [14C]-arachidonic acid, and the subsequent release of labelled prostaglandins was measured. Resting macrophages released measurable amounts of arachidonic acid, the prostaglandins E2, D2 and F2α and 6-oxoprostaglandin F1α. Phagocytosis of zymosan increased the release of arachidonic acid and prostaglandins to 2.5 times the control value. In contrast, phagocytosis of inert latex particles had no effect on prostaglandin release. Indomethacin inhibited the release of prostaglandin, and, at high doses (20μg/ml), increased arachidonic acid release. Analysis of the cellular lipids showed that after zymosan stimulation the proportion of label was decreased in phosphatidylcholine, but not in other phospholipids or neutral lipids. Cytochalasin B, at a dose of 2μg/ml, inhibited the phagocytosis induced by zymosan but increased prostaglandin synthesis to 3.4 times the control. These data suggest that the stimulation of prostaglandin synthesis by zymosan is not dependent on phagocytosis. Exposure to zymosan also resulted in the release of the lysosomal enzyme, acid phosphatase. Furthermore, cytochalasin B augmented the zymosan-stimulated release of acid phosphatase at the same dose that stimulated prostaglandin synthesis. However, indomethacin, at a dose that completely inhibited prostaglandin synthesis, failed to block the lysosomal enzyme release. Thus despite some parallels between the release of prostaglandins and lysosomal enzymes, endogenous prostaglandins do not appear to mediate the release of lysosomal enzymes. The prostaglandins released from the macrophages may function as humoral substances affecting other cells.


1980 ◽  
Vol 188 (3) ◽  
pp. 933-936 ◽  
Author(s):  
D W Riches ◽  
D R Stanworth

Cultured mouse peritoneal macrophages were found to release substantial amounts of lysosomal beta-glucuronidase and beta-glactosidase activites when exposed to millimolar concentrations of various primary aliphatic monoamines. With methylamine, ethylamine, propylamine and butylamine, lysosomal enzyme release was selective, but further increases in the aliphatic chain length resulted in the compounds becoming lytic. By contrast, structurally related primary aliphatic diamines proved to be inactive at inducing both selective and lytic lysosomal-enzyme discharge.


1974 ◽  
Vol 62 (3) ◽  
pp. 625-634 ◽  
Author(s):  
John L. Skosey ◽  
Evelyn Damgaard ◽  
Donald Chow ◽  
Leif B. Sorensen

During the process of phagocytosis, polymorphonuclear leukocytes (PMN) release lysosomal enzymes into the extracellular medium. When the antibiotic cytochalasin B (CB) is present in the incubation medium along with phagocytable particles, enhanced recovery of enzyme activities from the incubation medium has been observed. These findings have led to the interpretation that CB enhances lysosomal enzyme release. Our results contradict this interpretation. The lysosomal enzymes acid phosphatase and ß-galactosidase are unstable after they are released from cells. During the first 5–15 min of phagocytosis, significant amounts of both acid phosphatase and ß-galactosidase can be recovered from the extracellular medium. After this, the recovery of enzyme from the medium declines, presumably because the rate of loss of lysosomal enzyme activity exceeds the rate of release at later time periods. In the presence of CB, the appearance of lysosomal enzymes in the extracellular medium of cells exposed to zymosan is retarded for 5–10 min, after which it begins and then continues for approximately 20 min. At the end of a 30-min incubation period, therefore, in the absence of CB, extracellular levels of lysosomal enzymes (especially those which are unstable) are declining toward low levels while, in the presence of CB, extracellular enzyme levels are continuing to rise. We also measured the lysosomal enzyme remaining within cells after exposure to zymosan. CB retarded the disappearance of enzyme from cells and resulted in significantly less total cell enzyme loss. Thus, in the presence of CB, a greater proportion of the lysosomal enzyme lost from cells is recovered in the extracellular medium. In contrast to the previous conclusions that CB enhances lysosomal enzyme release, our results indicate that CB delays and decreases the zymosan-stimulated release of lysosomal enzymes from PMN. Since CB inhibits phagocytosis by PMN, our results indicate that the antibiotic modifies the mechanism of release of lysosomal enzymes, resulting in zymosan stimulation of their release independently of phagocytosis.


1978 ◽  
Vol 54 (2) ◽  
pp. 15P-15P
Author(s):  
R. Desai ◽  
H. Baum ◽  
D. Bellamy ◽  
D. C. S. Hutchison

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