Role of RPE cells in Age Related Macular Degeneration

Normal RPE cells form a single cell layer that supports the function of the retina. It is believed that the cells in this “monolayer” do not divide. Instead, they strongly adhere to each other and form cell-cell communications that support vision. Unfortunately, these cell adhesions and communication are lost because of inflammation in the wet form of AMD. When inflammation occurs, RPE cells secrete many growth factors and respond to them with their receptors. One of these factors is hepatocyte growth factor (HGF), which stimulates the division and migration of RPE and blood vessel endothelial cells. HGF also stimulates the production of other growth factors that promote the formation of new blood vessels and allow the invasion of the blood vessel cells into the neighboring matrix, which is an early event of neovascularization. Dr. Liou will study RPE cells treated with HGF to understand the mechanism of cell growth and migration induced by HGF. He will also examine surgically excised CNV membranes from patients with AMD to determine whether an HGF receptor is expressed in these membranes. He will study the role of HGF in CNV formation in mice by testing a recently discovered HGF-related protein, which has been shown to reduce new blood vessel formation in a number of tissues.