Platelet Derived Growth Factor (PDGF) is a potent mitogen for a wide range of cell types including fibroblasts, smooth muscle and connective tissue. PDGF, which is composed of a dimer of two chains termed the A chain and B chain, can be present as AA or BB homodimers or as an AB heterodimer. Human PDGF-BB is a 24.3 kDa B chain homodimer protein formed by subunits of 109 amino acid residues. MW: 24.3 kDa. Purity ≥98%