ABSTRACT
This chapter discusses the aspects Platelet-derived growth factor (PDGF), both in general and as it relates to pulmonary biology in health and disease. PDGF is a potent mitogen and chemotactic agent, which is a cationic glycoprotein named subsequent to its discovery in α granules of platelets. Amino acid sequences of the monomeric subunits soon revealed the presence of two distinct, but related, peptide chains termed A and B, which are linked by disulfide bonds. The similarities in the overall structure of the genes for PDGF-A and PDGF-B chains suggest a common ancestral origin by gene duplication. The precise phenotypic response of cells to PDGF depends on the availability of the cytokine, but also on the positioning of the receptor and its intracellular second-messenger signaling pathways. If the same cell both secretes PDGF and responds to it by virture of having the appropriate complement of PDGF receptors, the response pattern is described as autocrine.
