Multicenter evaluation of the hemostatic activity of emicizumab in patients with severe hemophilia A.

Background: Emicizumab has been approved for the prophylaxis of patients with hemophilia A with or without inhibitors. However, spontaneous and trauma-induced breakthrough bleeds have been reported in patients on emicizumab prophylaxis, and no laboratory assay has been validated to evaluate the hemostatic activity of emicizumab.

Objectives: The thrombin generation assay (TGA) could be a surrogate marker of the hemostatic efficacy of emicizumab.

The Ca- and phospholipid-binding protein Annexin A2 is able to increase and decrease plasma membrane order.

Annexin A2 (AnxA2) is a calcium- and phospholipid-binding protein that plays roles in cellular processes involving membrane and cytoskeleton dynamics and is able to associate to several partner proteins. However, the principal molecular partners of AnxA2 are negatively charged phospholipids such as phosphatidylserine and phosphatidyl-inositol-(4,5)-phosphate. Herein we have studied different aspects of membrane lipid rearrangements induced by AnxA2 membrane binding.

Cholesterol-pyrene as a probe for cholesterol distribution on ordered and disordered membranes: Determination of spectral wavelengths.

Biological membranes contain a large variety of lipids species compartmentalized in different domains heterogeneous in size, composition and dynamics. Cholesterol induces membrane ordered domains thanks to its affinity for saturated lipids. Membrane domains had been studied with fluorescent probes either linked to phospholipids and proteins or as individual fluorophore.