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 activity and promoting coagulation.

Mar 1, 2024 · Platelet factor 4 (PF4) combines with heparin to form an antigen that could produce IgG antibodies and participate in heparin-induced thrombocytopenia (HIT). PF4 has attracted wide attention due to its role in novel coronavirus vaccine-19 (COVID-9)-induced immune thrombotic thrombocytopenia (VITT) and cognitive impairments.

Mar 30, 2025 · PF4 (Platelet Factor 4) is a Protein Coding gene. Diseases associated with PF4 include Erythromelalgia and Essential Thrombocythemia. Among its related pathways are MIF Mediated Glucocorticoid Regulation and Response to elevated platelet cytosolic Ca2+.

Aug 16, 2023 · A newly identified platelet factor 4 (PF4) was found to help rejuvenate the old brain and boost the young brain, potentially opening the door to new therapies that aim to restore brain function

Antibodies against platelet factor 4 (PF4), a protein released from alpha-granules of activated platelets, may cause a number of pathophysiological conditions. The most commonly known is heparin-induced thrombocytopenia (HIT), which develops in a ...

Dec 8, 2023 · Antibodies against the chemokine platelet factor 4 (PF4) occur often, but only those that activate platelets induce severe prothrombotic disorders with associated thrombocytopenia.

Aug 15, 2007 · PF4, a member of the CXC family of chemokines, is the most abundant protein in platelet α-granules and is released into the local environment following platelet activation. Although characterized by its heparin-binding activity more than 50 years ago, 1 PF4's physiologic activities remain in question.

Platelet Factor 4 is a small chemokine sequestered in platelets, rapidly secreted upon activation, and known for neutralizing the effects of heparin on endothelial cells to promote coagulation. Additionally, it inhibits endothelial cell migration, proliferation, and angiogenesis both in …

Platelet factor 4 induces bone loss by inhibiting the integrin alpha5-FAK-ERK pathway. PF4 activates the c-Mpl-Jak2 pathway in platelets. New insights into the binding of PF4 to long heparin oligosaccharides in ultralarge complexes using mass spectrometry.

Platelet factor 4 (PF4, CXCL4) is a small chemokine protein released by activated platelets. Although a major physiological function of PF4 is to promote blood coagulation, this cytokine is involved in innate and adaptive immunity in events when ...