Gene/Protein
Disease
Symptom
Drug
Enzyme
Compound
Pivot Concepts:
Gene/Protein
Disease
Symptom
Drug
Enzyme
Compound
Target Concepts:
Gene/Protein
Disease
Symptom
Drug
Enzyme
Compound
Query: UNIPROT:P02749 (
beta2-glycoprotein I
)
836
document(s) hit in 31,850,051 MEDLINE articles (0.00 seconds)
The majority of the antiphospholipid antibodies, present in patients with antiphospholipid syndrome, are directed against conformational epitopes in
beta2-glycoprotein I
.
beta2-glycoprotein I
is an anionic phospholipid-binding 50-kDa plasma protein whose physiological role is not clear. Here we investigate the role of
beta2-glycoprotein I
in the phagocytosis of phosphatidylserine-expressing platelet microvesicles and the effect of autoantibodies to
beta2-glycoprotein I
on this process. We labelled the glycans of
beta2-glycoprotein I
with BODIPY (4,4-difluoro-4-bora-3a,4a-diaza-s-indacene)-hydrazide without affecting its phospholipid binding capacity. BODIPY-
beta2-glycoprotein I
bound to platelet microvesicles in a concentration-dependent manner and promoted the phagocytosis of platelet microvesicles by THP-1 derived macrophages in vitro at physiological plasma concentrations with a half maximal effect at approximately 10 microg/ml.
beta2-glycoprotein I
-stimulated phagocytosis was inhibited by annexin A5 and the phosphatidylserine-binding C1C2 fragment of
lactadherin
. Furthermore, immunoaffinity purified
beta2-glycoprotein I
-dependent antiphospholipid antibodies from five patients with antiphospholipid syndrome inhibited the phagocytosis in a concentration-dependent manner. These studies suggest that the binding of
beta2-glycoprotein I
to phosphatidylserine-expressing procoagulant platelet microvesicles may promote their clearance by phagocytosis and autoantibodies to
beta2-glycoprotein I
may inhibit this process to induce a procoagulant state.
...
PMID:Phagocytosis of platelet microvesicles and beta2- glycoprotein I. 2053 17
