PF4/CXCL4 (human, recombinant)

Platelet factor 4 (PF4), also known as chemokine (C-X-C) motif ligand 4 (CXCL4), is a chemokine produced by activated platelets with roles in coagulation, innate and adaptive immunity, and aging. It is produced as a 70-amino acid monomer, but functions as both a monomer and higher order oligomers in vivo. PF4 binds to heparin to inhibit its anticoagulation activity, and it facilitates platelet aggregation and interacts with chemokine (C-X-C) motif receptor 1 (CXCR1) and CXCR2 on polymorphonuclear leukocytes (PMNs) at sites of tissue injury to induce intramuscular accumulation and wound healing. It is released in response to microorganisms to induce neutrophil recruitment and in response to viral infection to stimulate antigen presenting cells and induce both pro- and antiviral effects. Plasma levels of PF4 are positively correlated with the progression of lung and skin fibrosis and pulmonary arterial hypertension. Decreased serum levels of PF4 are associated with cognitive decline in patients with Alzheimer's disease. Cayman's PF4/CXCL4 (human, recombinant) protein can be used for cell-based assay and Western blot (WB) applications. The protein was synthesized from a DNA sequence encoding the mature form of PF4 (Glu32-Ser101) with an N-terminal translation-initiating methionine (Met1). The expressed protein consists of 71 amino acids, has a calculated molecular weight of 7. kDa, and a predicted N-terminus of Met1.