Recombinant Human PDGF-AB (carrier-free)

Platelet-derived growth factors (PDGFs) are homo- or heterodimers of four polypeptides, known as A, B, C and D chains. PDGFs are primarily synthesized, stored in α-granules, and released by platelets upon activation. Five PDGF isoforms (AA, BB, AB, CC and DD) have been identified. PDGF-A and PDGF-B undergo intracellular activation during transport in the exocytic pathway and PDGF-C and PDGF-D are activated by extracellular proteases. PDGF-AA, AB, and BB dimers readily activate PDGF receptors (PDGFRs). PDGF-AA binds to PDGFRαα, PDGF-AB binds to PDGFRαα and PDGFRαβ, while PDGF-BB binds to the three dimeric receptors PDGFRαα, PDGFRαβ, and PDGFRββ. PDGFs are potent mitogens for connective tissue cells, including dermal fibroblasts, glial cells, arterial smooth muscle cells and some epithelial and endothelial cells. PDGFs act primarily in a paracrine manner and may be engaged in autocrine loops in tumors.  In addition to its activity as a mitogen, PDGF is a chemotactic for fibroblasts, smooth muscle cells, neutrophils and mononuclear cells. PDGF-AA and -AB promote cell proliferation, cell survival, cytoskeletal rearrangement, cell migration and extracellular matrix production. They are important for the development of oligodendrocytes, testicular Leydig cells, alveolar smooth muscle cells, hair follicles, and intestinal villi. Abnormalities of PDGFR/PDGF are thought to contribute to a number of human diseases, and especially malignancy. The combinantion of PDGF-AB and a nucleoside analog, 5-Azacytidine, induces primary somatic cells into tissue-regenerative multipotent stem cells.