Platelet Factor-4 (CXCL4) Variant-1, His-Tag, human recombinant (rHuPF4variant-His)

Released during platelet aggregation. Neutralizes the anticoagulant effect of heparin because it binds more strongly to heparin than to the chondroitin-4-sulfate chains of the carrier molecule. Chemotactic for neutrophils and monocytes. Inhibits endothelial cell proliferation, the short form is a more potent inhibitor than the longer form. (www.uniprot.org) Recombinant human CXCL4 Variant-1 produced in E.coli is a single, non-glycosylated polypeptide chain containing 77 amino acids and having a molecular mass of 8.7 kDa. The CXCL4 Variant-1 is fused to 6xHis tag at N-Terminus. Platelet factor-4 is a 70-amino acid protein that is released from the alpha-granules of activated platelets and binds with high affinity to heparin. Its major physiologic role appears to be neutralization of heparin-like molecules on the endothelial surface of blood vessels, thereby inhibiting local antithrombin III activity and promoting coagulation. As a strong chemoattractant for neutrophils and fibroblasts, PF4 probably has a role in inflammation and wound repair. Oncostatin-A is a member of the CXC chemocinfamily. Human PF4 is used for the proof of heparin-induced thrombocytopenia. Furthermore it is used as an inhibitor in the angiogenesis during tumor therapy.