Human Recombinant PF-4 (CXCL4)

Platelet factor 4 (PF-4), or CXCL4, is a member of the CXC chemokine family. It is produced by megakaryocytes, platelets, and cultured microglial cells (Kasper & Petersen; Wang & Huang). Although its receptors have not been fully characterized, PF-4 appears to affect p38/MAPK, PI3K/AKT, ERK, and JNK/c-Jun signaling pathways. PF-4 inhibits the development and maturation of megakaryocytes, and supports survival of hematopoietic stem and progenitor cells (Kasper & Petersen). PF-4 inhibits angiogenesis by suppressing endothelial cell proliferation and migration. It promotes inflammatory response through activation of granulocytes, T cells, and monocytes, which results in the release of oxygen radicals and cytokines, and induces phagocytosis. PF-4 stimulates NK cell migration, inhibits platelet coagulation, and together with TNF, PF-4 causes neutrophile degranulation (Kasper & Petersen; Wang & Huang).