Immunohistochemical localization of PDGF B, PDGF beta receptors and IGF I receptors during atherogenesis.

Growth factors and their receptors may be involved in initiation and progression of atherosclerotic intima changes. In this study, sections of human arteries in different stages of atherosclerosis were investigated for cellular expression of PDGF B, PDGF beta receptors and IGF I receptors. The applied immunohistochemical approach detected IGF I receptor synthesis in endothelial cells of atherosclerotic vessels. A possible role in atherogenesis may be seen in the control of IGF I transfer into subendothelial tissues. PDGF B chain production was observed in endothelial cells and macrophages in all stages of lesion development. The corresponding receptor for PDGF B (PDGF beta receptor) was expressed by transformed smooth muscle cells within the thickened intima from the stage of macrophage infiltration onwards. These results support the thesis that locally produced PDGF acts as a mitogen on smooth muscle cells and may promote proliferation during atherogenesis.