scholarly journals Changes in ionic movements across rabbit polymorphonuclear leukocyte membranes during lysosomal enzyme release. Possible ionic basis for lysosomal enzyme release.

1977 ◽  
Vol 75 (3) ◽  
pp. 635-649 ◽  
Author(s):  
P H Naccache ◽  
H J Showell ◽  
E L Becker ◽  
R I Sha'afi
Keyword(s):  
Lysosomal Enzyme ◽  
Polymorphonuclear Leukocytes ◽  
Cytochalasin B ◽  
Calcium Influx ◽  
Flow Diagram ◽  
Ionophore A23187 ◽  
Enzyme Release ◽  
45Ca Efflux ◽  
Ionic Movements ◽  
Ionic Basis

Changes in the movements of Na+, K+, and Ca+2 across rabbit neutrophils under conditions of lysosomal enzyme release have been studied. We have found that in the presence of cytochalasin B, the chemotactic factor formyl methionyl leucyl phenylalanine (FMLP) induces within 30 s large enhancements in the influxes of both 22Na+ and 45Ca+2 and an increase in the cellular pool of exchangeable calcium. The magnitude of the changes induced by cytochalasin B and FMLP exceeds that induced by FMLP or cytochalasin B alone, and cannot be explained on the basis of an additive effect of the two agents. However, these compounds either separately or together produce much smaller enhancements in 45Ca efflux. The divalent cation ionophore A23187 also produces a rapid and large increase in the influxes of both 22Na and 45Ca+2 in the presence and absence of cytochalasin B. We have also found an excellent correlation between calcium influx and lysosomal enzyme release. 42K influx is not significantly affected by any of these compounds. On the other hand, a large and rapid increase of 42K efflux is observed under conditions which give rise to lysosomal enzyme release. A flow diagram of the events that are thought to accompany the stimulation of polymorphonuclear leukocytes (PMNs) by chemotactic or degranulating stimuli is presented.

scholarly journals Pertussis toxin inhibition of chemotactic factor-induced calcium mobilization and function in human polymorphonuclear leukocytes.

1985 ◽  
Vol 162 (1) ◽  
pp. 145-156 ◽  
Author(s):  
D W Goldman ◽  
F H Chang ◽  
L A Gifford ◽  
E J Goetzl ◽  
H R Bourne
Keyword(s):  
Pertussis Toxin ◽  
Lysosomal Enzyme ◽  
Polymorphonuclear Leukocytes ◽  
Regulatory Protein ◽  
Leukotriene B4 ◽  
Ionophore A23187 ◽  
Enzyme Release ◽  
Adp Ribosylation ◽  
Chemotactic Factors ◽  
Human Polymorphonuclear Leukocytes

Chemotactic factors stimulate a rapid increase in the cytosolic concentration of intracellular calcium ions ([Ca2+]in) in human polymorphonuclear leukocytes (PMNL), which may be an event that is critical to the expression of chemotaxis and other PMNL functions. Treatment of PMNL with pertussis toxin catalyzes ADP-ribosylation of a protein similar or identical to the inhibiting regulatory protein of adenylate cyclase, Gi, and suppresses the increase in [Ca2+]in elicited by leukotriene B4(LTB4) and formyl-methionyl-leucyl-phenylalanine. Chemotactic migration and lysosomal enzyme release elicited by chemotactic factors were inhibited by pertussis toxin with a concentration-dependence similar to that for inhibition of the increase in [Ca2+]in, without an effect on lysosomal enzyme release induced by the ionophore A23187 and phorbol myristate acetate. Activated pertussis toxin catalyzed the [32P]ADP-ribosylation of a 41 kD protein in homogenates of PMNL. The extent of [32P]ADP-ribosylation of this protein was reduced 59% by pretreatment of intact PMNL with pertussis toxin. Pertussis toxin selectively decreased the number of high-affinity receptors for LTB4 on PMNL by 60% without altering the number or binding properties of the low-affinity subset of receptors. Pertussis toxin modification of a membrane protein of PMNL analogous to Gi thus simultaneously alters chemotactic receptors and attenuates the changes in cytosolic calcium concentration and PMNL function caused by chemotactic factors.

scholarly journals Role of microtubule assembly in lysosomal enzyme secretion from human polymorphonuclear leukocytes. A reevaluation.

1977 ◽  
Vol 73 (1) ◽  
pp. 242-256 ◽  
Author(s):  
S Hoffstein ◽  
I M Goldstein ◽  
G Weissmann
Keyword(s):  
Plasma Membrane ◽  
Dose Response ◽  
Lysosomal Enzyme ◽  
Polymorphonuclear Leukocytes ◽  
Cytochalasin B ◽  
Microtubule Assembly ◽  
Enzyme Release ◽  
Thin Sections ◽  
Human Polymorphonuclear Leukocytes ◽  
In Cells

The dose-related inhibition by colchicine of both lysosomal enzyme release and microtubule assembly was studied in human polymorphonuclear leukocytes (PMN) exposed to the nonphagocytic stimulus, zymosan-treated serum (ZTS). Cells were pretreated with colchicine (60 min, 37 degrees C) with or without cytochalasin B (5 microng/ml, 10 min) and then stimulated with ZTS (10%). Microtubule numbers in both cytochalasin B-treated and untreated PMN were increased by stimulation and depressed below resting levels in a dose-response fashion by colchicine concentrations above 10(-7) M. These concentrations also inhibited enzyme release in a dose-response fashion although the inhibition of microtubule assembly was proportionately greater than the inhibition of enzyme release. Other aspects of PMN morphology were affected by colchicine. Cytochalasin B-treated PMN were rounded, and in thin sections the retracted plasma membrane appeared as invaginations oriented toward centrally located centrioles. Membrane invaginations were restricted to the cell periphery in cells treated with inhibitory concentrations of colchicine, and the centrioles and Golgi apparatus were displaced from their usual position. After stimulation and subsequent degranulation, the size and number of membrane invaginations greatly increased. They remained peripheral in cells pretreated with greater than 10(-7) M colchicine but were numerous in the pericentriolar region in cells treated with less than 10(-7) M. Similarly, untreated PMN that were permitted to phagocytose immune precipitates had many phagosomes adjacent to the centriole. After colchicine treatment, phagosomes were distributed randomly, without any preferential association with the centrioles. These data suggest that microtubules are involved in maintaining the internal organization of cells and the topologic relationships between organelles and the plasma membrane.

scholarly journals Mechanisms of lysosomal enzyme release from human polymorphonuclear leukocytes. Effects of phorbol myristate acetate.

1975 ◽  
Vol 66 (3) ◽  
pp. 647-652 ◽  
Author(s):  
I M Goldstein ◽  
S T Hoffstein ◽  
G Weissmann
Keyword(s):  
Phorbol Myristate Acetate ◽  
Lysosomal Enzyme ◽  
Polymorphonuclear Leukocytes ◽  
Cytochalasin B ◽  
Enzyme Release ◽  
Myristate Acetate ◽  
Azurophil Granule ◽  
Cytoplasmic Microtubules ◽  
Specific Granule ◽  
Human Polymorphonuclear Leukocytes

PMA enhanced release of the azurophil granule enzyme, beta-glucuronidase, as well as lysozyme, from cytochalasin B-treated PMN's exposed to either zymosan particles or C5a. PMA was active at nanomolar concentrations, was not toxic to the cells, and was most effective when present for brief durations (0-1 min) before exposure of the cells to the stimuli. Beta-glucuronidase was not released in significant amounts from PMN's exposed to PMA alone, in the absence of stimuli such as zymosan or C5a. In contrast, only the specific granule enzyme, lysozyme, was released from unstimulated cells. Electron micrographs of cells exposed to PMA revealed an increase in the number of visible cytoplasmic microtubules as compared to control cells. Enhancement of lysosomal enzyme (beta-glucuronidase) release by PMA appears to be independent of effects on release of specific granule enzymes (lysozyme), but rather is likely due to PMA-induced elevations of cellular cGMP.

scholarly journals MODIFICATION OF ZYMOSAN-INDUCED RELEASE OF LYSOSOMAL ENZYMES FROM HUMAN POLYMORPHONUCLEAR LEUKOCYTES BY CYTOCHALASIN B

1974 ◽  
Vol 62 (3) ◽  
pp. 625-634 ◽  
Author(s):  
John L. Skosey ◽  
Evelyn Damgaard ◽  
Donald Chow ◽  
Leif B. Sorensen
Keyword(s):  
Acid Phosphatase ◽  
Lysosomal Enzyme ◽  
Incubation Medium ◽  
Polymorphonuclear Leukocytes ◽  
Lysosomal Enzymes ◽  
Cytochalasin B ◽  
Enhanced Recovery ◽  
Extracellular Enzyme ◽  
Enzyme Release ◽  
Extracellular Medium

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.

PLATELET-DEPENDENT ACTIVATION AND AMPLIFICATION OF THE POLYMORPHONUCLEAR LEUKOCYTES LYSOSOMAL ENZYME RELEASE

1987 ◽  
Author(s):  
A Del Maschio ◽  
E Corvazier ◽  
F Maillet ◽  
M Kazatchkine ◽  
J Maclouf
Keyword(s):  
Lysosomal Enzyme ◽  
Polymorphonuclear Leukocytes ◽  
Maximal Effect ◽  
Enzyme Release ◽  
Maximal Intensity ◽  
Platelet Concentration ◽  
Human Pmns ◽  
Stimulation Of

The degranulatlon of human PMNs by opsonlsed zymosan (OpZ) was studied In the presence or In the absence of platelet alone or after stimulation by thrombin. Evidence Is presented that the presence of platelets Increased the extent of the liberation of lysozyme from PMNs stimulated by OpZ with a maximal intensity when they were stimulated by thrombin. The extent of the amplification was higher when the PMNs trigger was lower (i.e. 0.5 x 108 particles/ml as compared to 3.0 x 108 particles). This effect was dependent on the platelet concentration (from 10-80 platelets/PMN). Platelets stimulated by thrombin could alsoactivate the resting PMNs with a maximum obtained ata thrombin concentration of 0.1 U/ml, corresponding to the maximal release by these cells of products stored In their granules. However, the substitution ofplatelet suspensions by the released products found In their supernatant after stimulation by thrombin, resulted In a comparable stimulation only at platelet concentrations above the ones for coincubation experiments. These findings suggest that the presence of platelets themselves or In combination with their released products are responsible for this amplification. The use of zymosan alone or coated with IgG, C3b1, C3b or OpZ did not reveal any specificity of the Inducer for this amplification suggesting that platelets and/or platelet products acted by enhancing acommon step of PMNs activation Independent of the stimulus carried by the particles. Additionally, It could be noted that the maximal effect of the amplification by platelets occurred when the level of stimulation of the PMNs alone was the weakest.

scholarly journals Response of the lysosomal system of the corneal epithelium to tyrosine-induced cell injury.

1977 ◽  
Vol 25 (12) ◽  
pp. 1351-1362 ◽  
Author(s):  
I K Gipson ◽  
R A Anderson
Keyword(s):  
Lysosomal Enzyme ◽  
Corneal Epithelium ◽  
Polymorphonuclear Leukocytes ◽  
Cell Injury ◽  
Tyrosine Aminotransferase ◽  
Multivesicular Bodies ◽  
Enzyme Release ◽  
Focal Lesions ◽  
Corneal Epithelial ◽  
Lysosomal System

Rats fed excess tyrosine develop corneal epithelial disease which parallels that found in humans with tyrosine aminotransferase deficiency (tyrosinosis). In the rat, focal lesions develop within the central epithelium and contain crystals (presumably tyrosine) that disrupt cells. We have studied these lesions and localized acid phosphatase and aryl sulfatase at the electron microscope level. Within 60 hr after initiation of diet, cells within the lesions showed an increase in lysosomal enzyme activity. This activity was localized inside some of the crystal ghosts and in numerous lysosomes, including autophagic vacuoles and multivesicular bodies. After 84 hr on diet the entire central corneal epithelium was disrupted and polymorphonuclear leukocytes had infiltrated the area. Crystals were phagocytosed by or developed within polymorphonuclear leukocytes. We hypothesize that crystals form within epithelial cells, disrupt first their lysosomes, and then cells, leading to externalization of lysosomal enzymes. This extracellular lysosomal enzyme release may be responsible for the acute inflammatory response that ensues.

FMLP-induced enzyme release from neutrophils: a role for intracellular calcium

1983 ◽  
Vol 245 (3) ◽  
pp. C196-C202 ◽  
Author(s):  
D. Chandler ◽  
G. Meusel ◽  
E. Schumaker ◽  
C. Stapleton
Keyword(s):  
Intracellular Calcium ◽  
Cytochalasin B ◽  
Calcium Ionophore ◽  
Cell Ultrastructure ◽  
Calcium Ionophore A23187 ◽  
Extracellular Calcium ◽  
Ionophore A23187 ◽  
Enzyme Release ◽  
Calcium Depletion ◽  
Dose Dependent

The ability of the chemotactic peptide N-formylmethionyl-leucyl-phenylalanine (FMLP) to stimulate beta-glucuronidase release and 45Ca2+ release from rabbit neutrophils was studied. FMLP stimulated enzyme release from cytochalasin B-treated cells either in the presence or the absence of extracellular calcium. Depletion of cell calcium, by exposure to either ethyleneglycol-bis(beta-aminoethylether)-N,N'-tetraacetic acid or the calcium ionophore A23187, blocked the ability of FMLP to stimulate enzyme release and 45Ca2+ release in the absence of extracellular calcium. The ability of A23187 to lower the 45Ca2+ content of neutrophils, to block FMLP-stimulated 45Ca2+ release, and to inhibit FMLP-stimulated enzyme release in the absence of calcium was dose dependent over the same concentration range (10(-8) to 10(-6) M A23187) for all three actions. In contrast, FMLP stimulated enzyme release from A23187-treated cells, provided that extracellular calcium was present. This secretory response was normal as judged by cell ultrastructure and FMLP dose-response relationships. It is concluded that A23187 depletes a pool of intracellular calcium usually released by FMLP and that release of calcium from this pool is necessary for initiation of enzyme secretion in the absence of extracellular calcium.

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