Switch to
| Predicate | Object |
|---|---|
| rdf:type | |
| lifeskim:mentions | |
| pubmed:issue |
24
|
| pubmed:dateCreated |
1996-8-20
|
| pubmed:abstractText |
L-Plastin is a calcium-regulated actin bundling protein expressed in leukocytes and some transformed cells, which is phosphorylated on serine in response to several different leukocyte-activating stimuli. Adhesion to immune complexes induced L-plastin phosphorylation in neutrophils, as did phagocytosis of IgG-opsonized particles, but insoluble immune complexes in suspension were very inefficient activators of L-plastin phosphorylation. Neutrophils express two IgG Fc receptors, the transmembrane FcgammaRII and the glycan phosphoinositol-linked FcgammaRIIIB. Use of monoclonal antibodies that distinguished the two Fc receptors demonstrated that FcgammaRII ligation was 100-fold more potent at signaling L-plastin phosphorylation than occupancy of FcgammaRIIIB. Depletion of intracellular calcium did not affect FcgammaRII-activated L-plastin phosphorylation, demonstrating that any potential regulation of plastin function by calcium did not affect its phosphorylation. Adhesion to immune complexes caused L-plastin to localize to podosomes, since it colocalized with actin to discrete, punctate Triton X-100-insoluble sites on the adherent neutrophil surface in a pattern indistinguishable from vinculin and alpha-actinin. Nonetheless, localization to podosomes was not required for L-plastin phosphorylation, since both neutrophils from a patient with leukocyte adhesion deficiency (CD18 deficiency) and neutrophils treated with anti-CD18 F(ab')2, which do not form podosomes upon adhesion to immune complexes, phosphorylated L-plastin normally. Indeed, L-plastin was normally phosphorylated in response to adhesion to immune complexes even when the actin cytoskeleton was disrupted with cytochalasin D. We conclude that efficient FcgammaRII-mediated phosphorylation of L-plastin requires cell adhesion but does not require IgG-induced rearrangements of the actin cytoskeleton. These data suggest a model in which plastin phosphorylation and localization to the actin cytoskeleton can act as two distinct mechanisms regulating L-plastin functions in neutrophils adherent to immune complexes.
|
| pubmed:grant | |
| pubmed:language |
eng
|
| pubmed:journal | |
| pubmed:citationSubset |
IM
|
| pubmed:chemical |
http://linkedlifedata.com/resource/pubmed/chemical/Actinin,
http://linkedlifedata.com/resource/pubmed/chemical/Antibodies, Monoclonal,
http://linkedlifedata.com/resource/pubmed/chemical/Antigens, CD,
http://linkedlifedata.com/resource/pubmed/chemical/Antigens, CD18,
http://linkedlifedata.com/resource/pubmed/chemical/Calcium,
http://linkedlifedata.com/resource/pubmed/chemical/Egtazic Acid,
http://linkedlifedata.com/resource/pubmed/chemical/Immunoglobulin Fab Fragments,
http://linkedlifedata.com/resource/pubmed/chemical/Membrane Glycoproteins,
http://linkedlifedata.com/resource/pubmed/chemical/Microfilament Proteins,
http://linkedlifedata.com/resource/pubmed/chemical/N-Formylmethionine...,
http://linkedlifedata.com/resource/pubmed/chemical/Phosphoproteins,
http://linkedlifedata.com/resource/pubmed/chemical/Receptors, IgG,
http://linkedlifedata.com/resource/pubmed/chemical/Tetradecanoylphorbol Acetate,
http://linkedlifedata.com/resource/pubmed/chemical/Vinculin,
http://linkedlifedata.com/resource/pubmed/chemical/plastin
|
| pubmed:status |
MEDLINE
|
| pubmed:month |
Jun
|
| pubmed:issn |
0021-9258
|
| pubmed:author | |
| pubmed:issnType |
Print
|
| pubmed:day |
14
|
| pubmed:volume |
271
|
| pubmed:owner |
NLM
|
| pubmed:authorsComplete |
Y
|
| pubmed:pagination |
14623-30
|
| pubmed:dateRevised |
2008-11-21
|
| pubmed:meshHeading |
pubmed-meshheading:8663066-Actinin,
pubmed-meshheading:8663066-Antibodies, Monoclonal,
pubmed-meshheading:8663066-Antigens, CD,
pubmed-meshheading:8663066-Antigens, CD18,
pubmed-meshheading:8663066-Calcium,
pubmed-meshheading:8663066-Cell Adhesion,
pubmed-meshheading:8663066-Cell Membrane,
pubmed-meshheading:8663066-Cells, Cultured,
pubmed-meshheading:8663066-Egtazic Acid,
pubmed-meshheading:8663066-Humans,
pubmed-meshheading:8663066-Immunoglobulin Fab Fragments,
pubmed-meshheading:8663066-Kinetics,
pubmed-meshheading:8663066-Leukocyte-Adhesion Deficiency Syndrome,
pubmed-meshheading:8663066-Membrane Glycoproteins,
pubmed-meshheading:8663066-Microfilament Proteins,
pubmed-meshheading:8663066-N-Formylmethionine Leucyl-Phenylalanine,
pubmed-meshheading:8663066-Neutrophils,
pubmed-meshheading:8663066-Phagocytosis,
pubmed-meshheading:8663066-Phosphoproteins,
pubmed-meshheading:8663066-Phosphorylation,
pubmed-meshheading:8663066-Receptors, IgG,
pubmed-meshheading:8663066-Tetradecanoylphorbol Acetate,
pubmed-meshheading:8663066-Vinculin
|
| pubmed:year |
1996
|
| pubmed:articleTitle |
FcgammaRII-mediated adhesion and phagocytosis induce L-plastin phosphorylation in human neutrophils.
|
| pubmed:affiliation |
Division of Infectious Diseases, Washington University School of Medicine, St. Louis, Missouri 63110, USA.
|
| pubmed:publicationType |
Journal Article,
Research Support, U.S. Gov't, P.H.S.
|