Linked Life Data

1591882

Source:http://linkedlifedata.com/resource/pubmed/id/1591882

Statements in which the resource exists as a subject.
PredicateObject
rdf:type
lifeskim:mentions
pubmed:issue
1
pubmed:dateCreated
1992-7-2
pubmed:abstractText
Previous studies identified specific receptors for C1q on human blood platelets in purified systems using monomeric C1q. To assess the physiologic potential of platelet C1q receptors, C1q binding was evaluated in whole blood and in the presence of immune complexes or aggregated IgG. Blood was obtained from healthy volunteers and collected directly into EDTA (1 vol 100mM EDTA:9 vol whole blood) and purified, 125I-labeled C1q or 125I-C1q associated with albumin-anti-albumin immune complexes. Samples were incubated at 22 or 37 degrees C for 60 min, and total cell bound C1q and platelet associated C1q were quantified. Platelet-bound, monomeric C1q or immune complex-associated C1q represented 40-50% of total peripheral blood cell-associated C1q. C1q binding was unaffected by the incubation temperature, but the preincubation of 125I-C1q with immune complexes enhanced binding two- to threefold. This binding was partially inhibited by preincubating platelets with either the collagen-like amino-terminal fragments of C1q (c-C1q) or a monoclonal antibody Fab fragment recognizing platelet Fc receptors. A more complete inhibition was achieved if platelets were preincubated with both agents. Similar observations were made using washed platelets and 125I-C1q associated with aggregated IgG. The role of C1q and platelet C1q receptors in enhancing aggregated-IgG binding to platelets was further supported by experiments demonstrating increased 125I-aggregated IgG binding to platelets not only after preincubation of 125I-aggregated IgG with C1q but also following platelet preincubation with C1q. These data suggest that C1q receptors may participate in the localization and presentation of C1q-associated immune complexes on the platelet surface and demonstrate that platelets contribute significantly to the C1q binding activity of peripheral blood.
pubmed:grant
pubmed:language
eng
pubmed:journal
pubmed:citationSubset
IM
pubmed:chemical
http://linkedlifedata.com/resource/pubmed/chemical/Antigen-Antibody Complex, http://linkedlifedata.com/resource/pubmed/chemical/Antigens, CD44, http://linkedlifedata.com/resource/pubmed/chemical/C1QBP protein, human, http://linkedlifedata.com/resource/pubmed/chemical/Carrier Proteins, http://linkedlifedata.com/resource/pubmed/chemical/Complement Activating Enzymes, http://linkedlifedata.com/resource/pubmed/chemical/Complement C1q, http://linkedlifedata.com/resource/pubmed/chemical/Immunoglobulin G, http://linkedlifedata.com/resource/pubmed/chemical/Membrane Glycoproteins, http://linkedlifedata.com/resource/pubmed/chemical/Mitochondrial Proteins, http://linkedlifedata.com/resource/pubmed/chemical/Receptors, Complement, http://linkedlifedata.com/resource/pubmed/chemical/complement 1q receptor
pubmed:status
MEDLINE
pubmed:month
Apr
pubmed:issn
0090-1229
pubmed:author
pubmed:issnType
Print
pubmed:volume
63
pubmed:owner
NLM
pubmed:authorsComplete
Y
pubmed:pagination
45-50
pubmed:dateRevised
2007-11-14
pubmed:meshHeading
pubmed:year
1992
pubmed:articleTitle
Platelet interactions with C1q in whole blood and in the presence of immune complexes or aggregated IgG.
pubmed:affiliation
Department of Pathology, SUNY, Stony Brook 11794-7300.
pubmed:publicationType
Journal Article, Comparative Study, In Vitro, Research Support, U.S. Gov't, P.H.S., Research Support, Non-U.S. Gov't