The major antigen in APS is beta-2-glycoprotein I (β2-GPI) is known to complex with annexin A2 (ANXA2), and antibodies to ANXA2 have been described in APS.
The discovery in the 1990s that the protein beta-2-glycoprotein I (β<sub>2</sub>GPI) was an antigen of central importance in the antiphospholipid syndrome (APS) was soon followed by the development of ELISA assays capable of identifying anti-β<sub>2</sub>GPI antibodies recognizing this antigen.
We investigated the cytokine production induced by β2GPI in activated T cells that infiltrate in vivo atherosclerotic lesions of primary APS patients with atherothrombosis.
HETE-PLs enhanced membrane binding of the serum protein β2GP1 (β2-glycoprotein 1), an event considered central to the autoimmune reactivity responsible for APS symptoms.
At least one clinical (vascular thrombosis or pregnancy morbidity) and one lab-based (positive test result for lupus anticoagulant, anticardiolipin antibodies and/or anti-β2-glycoprotein 1 antibodies) criterion have to be met for a patient to be classified as having APS.
To test the role of IgA anti B2GP1 as a risk factor for the development of APS-events (thrombosis or pregnancy morbidity) in asymptomatic population with a 5-year follow-up.
Novel evidence of β2-glycoprotein I/antibody complex bioactivities may provide insight into the molecular mechanisms that the complex regulates cell function and involves in APS pathogenesis.
Background There is general consensus that the antiphospholipid syndrome (APS) is caused by antiphospholipid antibodies (aPL) with antibodies against β2-glycoprotein-I being the most relevant. aPL that bind phospholipids in the absence of protein cofactors are generally considered pathogenetically irrelevant.
A1-A1 binds to β2GPI/antibody complexes, preventing their association with ApoER2 and anionic phospholipids, and reducing thrombus size in the mouse model of APS.
The scFv-Fc directed against β2GPI domain I-induced thrombosis and fetal loss, thus mimicking the effect of antibodies from patients with antiphospholipid syndrome (APS).
We evaluated early atherosclerosis in patients with SLE and APS and investigated T cell reactivity to β2GPI and its relationship with atherosclerotic process.
Antiphospholipid antibodies (aPL), particularly against the phospholipid binding protein beta-2 glycoprotein I (β2GPI), play an important role in APS pathological mechanisms. aPL can activate intracellular signal transduction in a β2GPI-dependent manner to induce inflammatory responses, and promote hypercoagulable state and recurrent spontaneous abortion when β2GPI is associated with the cell surface receptor.
Overall, our results indicate that anti-β(2)GPI/β(2)GPI complex induced TF and TNF-α expression involving both TLR4/MyD88 and TLR4/TRIF signaling pathways and TLR4 and its adaptors might be molecular targets for therapy of antiphospholipid syndrome (APS).
Val/Val genotype of β(2)-GPI gene is associated with a significant excess risk to suffer from APS and, among patients with APS, to have anti-β(2)-GPI antibodies.
This meta-analysis shows that the β(2)GPI Val/Leu(247) polymorphism is associated with susceptibility to APS and thrombosis and with anti-β(2)GPI positivity.
These findings hold promise, not only for the delineation of the role of β2GPI as an immunological target, but also for the development of improved diagnostic and prognostic assays for APS.
The antiphospholipid syndrome (APS) is a systemic autoimmune disease characterized by vascular thrombosis and/or pregnancy complications (lower fecundity and lower litter size), as well as by an increase in anti-β(2) glycoprotein I (β(2) GPI)-specific autoantibody titer.
In antiphospholipid syndrome (APS), antiphospholipid antibodies (aPL) binding to β2 glycoprotein I (β2GPI) induce endothelial cell-leukocyte adhesion and thrombus formation via unknown mechanisms.
We examined the in vitro effects of IgG fractions from patients with antiphospholipid syndrome (APS) and of a beta-2-glycoprotein 1-independent human monoclonal antiphospholipid antibody (HL-5B) on human umbilical vein endothelial cells (HUVEC) in comparison to untreated cell controls and to exposure to monoclonal IgG control antibody.
Genetic studies of a representative antigen, beta2-glycoprotein-I (beta(2)GPI), have been carried-out and a particular valine(247)/leucine polymorphism could be a genetic risk for presenting anti-beta(2)GPI antibodies and APS.
In the antiphospholipid syndrome (APS), pathogenic antiphospholipid antibodies (aPL) that cause thrombosis or pregnancy morbidity are characterized by binding to anionic phospholipids (PL) and beta2-glycoprotein I (beta(2)GPI).