PDGF (Platelet-Derived Growth Factor) is mainly involved in the regulation of migration and proliferation of mesenchymal cells. PDGRF (PDGF Receptor) family belongs to type III class of RTK receptors, and includes PDGFR, CSF-1R, KIT, FLT3 among others. The over-expression of PDGF and PDGFR is believed to correlate with development of arteriosclerosis and fibrous growth disease.