platelet-derived growth factor ( pdgf ) consists of three different isoforms , pdgf-aa , pdgf-ab and pdgf-bb , which bind to at least two types of receptors : the b-receptor , to which only pdgf-bb binds , and the a/b receptor , to which all three isoforms bind .
C0032200
pdgf
C0381163
pdgf-ab