Platelet Factor 4 (PF4) is a small high-affinity heparin binding protein localized in the a-granules of platelets and megacaryocytes.
It is a member of a multigene “intercrine-cytokine” family that includes a-thromboglobulin, connective tissue activating peptide III, monocyte-derived neutrophil chemotactic factor and melanoma growth stimulatory factor.
Human PF4 consists of 70aa and has a mass of 7800D.
In the platelet, PF4 exists as a homo-tetramer in complex with a high-molecular weight proteoglycan carrier.
PF4 is one of the most abundant proteins in the platelet a-granule and is considered platelet-specific, as its concentration in platelets is more than 20,000-fold greater than in plasma.
The heparin neutralization activity of PF4 is believed to be due to the presence of four lysine residues interspersed among pairs of aliphatic residues in the C-terminal region of the molecule.
During vessel injury, platelets are stimulated by thrombin or other agonists to release a-granule contents at the site of injury.
Presumably the potent heparin neutralization activity of PF4 would reduce the anticoagulant activity of antithrombin, prolonging the action of thrombin and activated factor X to promote clot formation.
Released PF4 also binds to heparin-like molecules on the surface of endothelial cells and hepatocytes, neutralizing the anticoagulant activity expressed by these cells.
Some of the other activities attributable to PF4 include the potentiation of platelet aggregation, stimulation of fibroblast attachment to substrata, chemotactic activity with respect to neutrophils and inhibition of contact activation.
Applications:Suitable for use in ELISA and Immunoelectrophoresis.
Other applications not tested.
Recommended Dilutions:Optimal dilutions to be determined by the researcher.
Rz Ratio (Reiheitszahl, A403/A280): 0.41
Storage and Stability:Store product at 4°C if to be used immediately within two weeks.
For long-term storage, aliquot to avoid repeated freezing and thawing and store at -20°C.
Aliquots are stable at -20°C for 12 months after receipt.
Dilute required amount only prior to immediate use.
Further dilutions can be made in assay buffer.
Note: Sodium azide is a potent inhibitor of peroxidase and should not be added to HRP conjugates.
For maximum recovery of product, centrifuge the original vial after thawing and prior to removing the cap.
仕様
Size：200ug
Host：sheep
Source Antibody：human
Grade：Purified
Purity：Purified.
Form：Supplied as a liquid in a buffered stabilizer solution, 50% glycerol. Labeled with Horseradish Peroxidase (HRP).
Specificity：Recognizes human PF4.
Isotype：IgG
Calc Applications Abbrev：E
Calc Crossreactivity：Hu
Immunogen：Platelet Factor 4 (PF4) purified from human platelet concentrate.
