Domain V of β2-Glycoprotein I Binds Factor XI/XIa and Is Cleaved at Lys317-Thr318

Optimization of Unnicked β2-Glycoprotein I and High Avidity Anti-β2-Glycoprotein I Antibodies Isolation

Patient biological material for isolation of β2-glycoprotein I (β2GPI) and high avidity IgG anti-β2-glycoprotein I antibodies (HAv anti-β2GPI) dictates its full utilization. The aim of our study was to evaluate/improve procedures for isolation of unnicked β2GPI and HAv aβ2GPI to gain unmodified proteins in higher yields/purity. Isolation of β2GPI from plasma was a stepwise procedure combining n...

Truncated semenogelin I binds zinc and is cleaved by prostate-specific antigen.

Semenogelins I and II are major coagulum-forming proteins in semen, and they are secreted mainly by the seminal vesicles. These proteins bind Zn(2+) and act as substrates for prostate-specific antigen and transglutaminase. A variant semenogelin I lacking 60 amino acids has been described that occurs in different populations with an allele frequency of 1%-3%. To better understand the function of...

Structural Changes in β2-Glycoprotein I and the Antiphospholipid Syndrome

Redox control of β2-glycoprotein I–von Willebrand factor interaction by thioredoxin-1

BACKGROUND  β(2) -Glycoprotein I (β(2) GPI) is an abundant plasma protein that is closely linked to blood clotting, as it interacts with various protein and cellular components of the coagulation system. However, the role of β(2) GPI in thrombus formation is unknown. We have recently shown that β(2) GPI is susceptible to reduction by the thiol oxidoreductases thioredoxin-1 and protein disulfide...

2-Glycoprotein I binds factor XI and inhibits its activation by thrombin and factor XIIa: Loss of inhibition by clipped 2-glycoprotein I

Activation of factor XI (FXI) by thrombin in vivo plays a role in coagulation by providing an important positive feedback mechanism for additional thrombin generation. FXI is activated in vitro by thrombin, or FXIIa in the presence of dextran sulfate. In this report, we investigated the effect of 2-glycoprotein I ( 2GPI) on the activation of FXI. 2GPI bound FXI in vitro and inhibited its activa...