CXCL4 / PF4 Protein

• Description:

  Platelet factor 4 (PF4), also known as chemokine (C-X-C motif) ligand 4 (CXCL4), is a small cytokine belonging to the CXC chemokine family. CXCL4/PF4 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, CXCL4/PF4 probably has a role in inflammation and wound repair. This protein is released during platelet aggregation. CXCL4/PF4 neutralizes the anticoagulant effect of heparin because it binds more strongly to heparin than to the chondroitin-4-sulfate chains of the carrier molecule. CXCL4 is chemotactic for neutrophils and monocytes. It inhibits endothelial cell proliferation, the short form is a more potent inhibitor than the longer form. CXCL4/PF4 is up-regulated in human liver fibrosis and that it plays a nonredundant, functional role in experimental liver fibrosis by mediating stellate cell proliferation, migration, and intrahepatic immune cell recruitment.

• Synonyms:

  CXCL4 Protein; PF-4 Protein; SCYB4 Protein

• Accession Number:

  NP_002610.1

• Reactivity:

  Human

• Cross Reactivity:

  Human

• Assay Protocol:

  See Datasheet send with the product

• Endotoxin:

  < 1.0 EU per μg of the protein as determined by the LAL method

• Purity:

  > 90 % as determined by SDS-PAGE

• Bioactivity:

  Measured by its ability to inhibit bFGF-dependent proliferation of human umbilical vein endothelial cells (HUVEC) . The ED50 for this effect is typically 1-5μg/mL in the presence of 5 ng/mL bFGF.

• Length:

  71

• Form:

  Lyophilized

• Buffer:

  PBS, pH 7.4

• Reconstitution:

  See Datasheet

• Molecular Weight:

  7.8 kDa

• Storage Conditions:

  Samples are stable for up to twelve months from date of receipt at -20°C to -80°C. Store it under sterile conditions at -20°C to -80°C. It is recommended that the protein be aliquoted for optimal storage. Avoid repeated freeze-thaw cycles.

• Host or Source:

  E.coli