Resurfacing of diseased or iatrogenically damaged Bruch's membrane with healthy retinal pigment epithelium (RPE) has been proposed as adjunctive treatment for age-related macular degeneration (AMD). However, aged submacular Bruch's membrane does not support transplanted RPE survival and differentiation. With aging and AMD, Bruch's membrane undergoes numerous changes that could affect ligand availability. These observations lead to the following hypothesis: Aging changes mask extracellular matrix ligand availability to transplanted RPE cells, impairing post-attachment events and leading, in turn, to cell death or inability of the cells to differentiate. The following specific aims will determine whether cell health can be improved by resurfacing Bruch's membrane with bovine corneal endothelial cell extracellular matrix (BCE-ECM), a matrix that supports RPE growth and differentiation.
Aim 1 : Determine whether bovine corneal endothelial cells (BCE) can """"""""resurface"""""""" Bruch's membrane.
Aim 2 : Determine whether cultured RPE cells can form focal adhesions on BCE-ECM-coated RPE basement membrane/Bruch's membrane and whether short-term cell survival is improved.
Aim 3 : Determine whether RPE cell longer-term survival is improved on BCE-ECM-coated Bruch's membrane. These studies will utilize an organ explant culture system of aged, human submacular Bruch's membrane. Resurfacing will be accomplished by culturing BCE on explants for a period of time to allow BCE-ECM deposition, followed by removal of cells and seeding with cultured RPE cells. Explants will be analyzed with scanning, light, and confocal microscopy. If RPE survival and differentiation are enhanced via this approach, the studies will lay the foundation for further studies using ligand components of BCE-ECM, which could form a basis for clinical treatment of Bruch's membrane to enhance RPE graft survival in AMD patients following choroidal new vessel (CNV) excision.
| Zarbin, Marco Attilio (2008) Retinal pigment epithelium-retina transplantation for retinal degenerative disease. Am J Ophthalmol 146:151-3 |
