Linked Life Data

8656062

Source:http://linkedlifedata.com/resource/pubmed/id/8656062

Statements in which the resource exists as a subject.
PredicateObject
rdf:type
lifeskim:mentions
pubmed:issue
5
pubmed:dateCreated
1996-8-1
pubmed:abstractText
Tyrosine kinases play a prominent role in various intracellular signal transduction pathways. In this study, beta2 integrin (CD11/CD18)-mediated adhesive interactions of human neutrophils (PMN) were mimicked by antibody cross-linking of CD11/CD18. Cross-linking of CD18 induced tyrosine phosphorylation of several proteins with apparent molecular masses of approximately 120, 78, 72, 65, and 56 kDa, respectively, as shown by anti-phosphotyrosine immunoblotting of whole cell lysates. Cross-linking of the alpha-subunits of the beta2 integrins demonstrated that only cross-linking of Mac-1 but not LFA-1 or gp150/95 triggered tyrosine signaling. The tyrosine phosphorylations showed a rapid and transient time course. Comparison of the CD18-mediated tyrosine phosphorylation patterns with those induced by chemoattractants gave similar results. The observed tyrosine phosphorylation was specific, since binding and non-binding irrelevant primary antibodies had no effect. Furthermore, F(ab')2 fragments of the anti-CD18 antibody IB4 and addition of F(ab')2 fragments of secondary antibody were sufficient to induce tyrosine phosphorylation. Inhibition of tyrosine kinases by herbimycin A resulted in partial inhibition of the CD18-mediated tyrosine phosphorylation of the 120- and 65-kDa proteins and in complete inhibition of tyrosine phosphorylation of the 78- and 56-kDa proteins. In unstimulated PMN, the tyrosine phosphatase inhibitor sodium orthovanadate had no effect on tyrosine phosphorylation of the 120-kDa protein, but induced phosphorylation of the 78-, 72-, 65-, and 56-kDa proteins. These results indicate that the beta2 integrin-mediated intracellular signaling cascade involves different tyrosine phosphorylation (and dephosphorylation) events, which may play a role in the regulation of PMN functions during inflammation.
pubmed:language
eng
pubmed:journal
pubmed:citationSubset
IM
pubmed:chemical
pubmed:status
MEDLINE
pubmed:month
May
pubmed:issn
0741-5400
pubmed:author
pubmed:issnType
Print
pubmed:volume
59
pubmed:owner
NLM
pubmed:authorsComplete
Y
pubmed:pagination
747-53
pubmed:dateRevised
2006-11-15
pubmed:meshHeading
pubmed:year
1996
pubmed:articleTitle
Beta2 integrins mediate protein tyrosine phosphorylation in human neutrophils.
pubmed:affiliation
Department of Physiology, Freie Universität Berlin, Germany.
pubmed:publicationType
Journal Article, Research Support, Non-U.S. Gov't