scholarly journals Mechanisms of Lysosomal Enzyme Release from Human Leukocytes II. EFFECTS OF cAMP AND cGMP, AUTONOMIC AGONISTS, AND AGENTS WHICH AFFECT MICROTUBULE FUNCTION

1974 ◽  
Vol 53 (1) ◽  
pp. 297-309 ◽  
Author(s):  
Robert B. Zurier ◽  
Gerald Weissmann ◽  
Sylvia Hoffstein ◽  
Sandra Kammerman ◽  
Hsin Hsiung Tai
Keyword(s):  
Lysosomal Enzyme ◽  
Enzyme Release ◽  
Human Leukocytes ◽  
Camp And Cgmp ◽  
Microtubule Function

Dissociation of phagocytosis, metabolic stimulation and lysosomal enzyme release in human leukocytes

1976 ◽  
Vol 6 (1-3) ◽  
pp. 256-259 ◽  
Author(s):  
Dirk Roos ◽  
Ira M. Goldstein ◽  
Howard B. Kaplan ◽  
Gerald Weissmann
Keyword(s):  
Lysosomal Enzyme ◽  
Enzyme Release ◽  
Human Leukocytes ◽  
Metabolic Stimulation

scholarly journals MECHANISMS OF LYSOSOMAL ENZYME RELEASE FROM HUMAN LEUKOCYTES

1973 ◽  
Vol 58 (1) ◽  
pp. 27-41 ◽  
Author(s):  
Robert B. Zurier ◽  
Sylvia Hoffstein ◽  
Gerald Weissmann
Keyword(s):  
Plasma Membrane ◽  
Lysosomal Enzyme ◽  
Immune Complexes ◽  
Cyclic Nucleotides ◽  
Lysosomal Enzymes ◽  
Plasma Membranes ◽  
Prostaglandin E ◽  
Enzyme Release ◽  
Human Leukocytes ◽  
Oxidation Of Glucose

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.

Spinal Cord Edema, 5-Hydroxytryptamine, Lipid Peroxidation, and Lysosomal Enzyme Release After Acute Contusion and Compression Injury in Primates

1985 ◽  
Vol 2 (1) ◽  
pp. 45-58 ◽  
Author(s):  
JACOB ABRAHAM ◽  
AIYLAM S. BALASUBRAMANIAN ◽  
D.R. THEODORE ◽  
SHANMUGAM NAGARAJAN ◽  
C.A. APTE ◽  
...  
Keyword(s):  
Spinal Cord ◽  
Lipid Peroxidation ◽  
Lysosomal Enzyme ◽  
Enzyme Release ◽  
Compression Injury ◽  
Spinal Cord Edema

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.

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