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rdf:type | |
lifeskim:mentions | |
pubmed:issue |
30
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pubmed:dateCreated |
1992-11-25
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pubmed:abstractText |
The interrelationships between activation of phospholipases and neutrophil stimulus-induced Ca2+ responses remain unclear. We report here that immune complexes activate a phosphatidylcholine-specific phospholipase A in a neutrophil only after the cytoplasmic Ca2+ transient has been initiated in the same cell, while chemotactic peptide activation does not proceed via such a phospholipase A-mediated mechanism. Measurements of [Ca2+] changes and of phosphatidylcholine-specific phospholipase A activity were made by flow cytometry, using Indo-1 for Ca2+ indication, and a new fluorescent probe, bis-BODIPY-phosphatidylcholine, localized in the inner leaflet of the plasma membrane, to measure phospholipase A activation. Both 100 nM formyl-methionyl-leucyl-phenylalanine (with or without cytochalasin B) and 60 micrograms/ml insoluble immune complexes elicited cytoplasmic Ca2+ transients, but only insoluble immune complexes stimulated phospholipase A activation in a subpopulation of cells exhibiting an elevation of [Ca2+]in. Phospholipase A activation followed the Ca2+ transient, starting, in each cell, after [Ca2+]in had begun to decrease as Ca2+ redistributed in the activated cell. The products of this phospholipase activation were confirmed by thin layer chromatography. We conclude that neutrophils respond to immune complexes with an elevated cytoplasmic Ca(2+)-requiring phosphatidylcholine-specific phospholipase A activation and to chemotactic peptides by a different mechanism.
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pubmed:grant | |
pubmed:language |
eng
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pubmed:journal | |
pubmed:citationSubset |
IM
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pubmed:chemical |
http://linkedlifedata.com/resource/pubmed/chemical/Boron Compounds,
http://linkedlifedata.com/resource/pubmed/chemical/Calcium,
http://linkedlifedata.com/resource/pubmed/chemical/Fluorescent Dyes,
http://linkedlifedata.com/resource/pubmed/chemical/Liposomes,
http://linkedlifedata.com/resource/pubmed/chemical/N-Formylmethionine...,
http://linkedlifedata.com/resource/pubmed/chemical/Phosphatidylcholines,
http://linkedlifedata.com/resource/pubmed/chemical/Phospholipases A
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pubmed:status |
MEDLINE
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pubmed:month |
Oct
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pubmed:issn |
0021-9258
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pubmed:author | |
pubmed:issnType |
Print
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pubmed:day |
25
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pubmed:volume |
267
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pubmed:owner |
NLM
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pubmed:authorsComplete |
Y
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pubmed:pagination |
21465-70
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pubmed:dateRevised |
2007-11-14
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pubmed:meshHeading |
pubmed-meshheading:1400459-Boron Compounds,
pubmed-meshheading:1400459-Calcium,
pubmed-meshheading:1400459-Cells, Cultured,
pubmed-meshheading:1400459-Enzyme Activation,
pubmed-meshheading:1400459-Flow Cytometry,
pubmed-meshheading:1400459-Fluorescent Dyes,
pubmed-meshheading:1400459-Humans,
pubmed-meshheading:1400459-Kinetics,
pubmed-meshheading:1400459-Liposomes,
pubmed-meshheading:1400459-N-Formylmethionine Leucyl-Phenylalanine,
pubmed-meshheading:1400459-Neutrophils,
pubmed-meshheading:1400459-Phosphatidylcholines,
pubmed-meshheading:1400459-Phospholipases A
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pubmed:year |
1992
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pubmed:articleTitle |
Flow cytometric kinetic measurements of neutrophil phospholipase A activation.
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pubmed:affiliation |
Boston University School of Medicine, Massachusetts 02118.
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pubmed:publicationType |
Journal Article,
Research Support, U.S. Gov't, P.H.S.
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