|
|
||||||||
1From the Department of Ophthalmology and Visual Sciences and the 2Institute for Cellular Therapeutics, University of Louisville, Louisville, Kentucky; and the 3Department of Ophthalmology, Inselspital, University of Bern, Bern, Switzerland.
PURPOSE. The aim of the present study was to investigate whether bone marrow–derived cells (BMCs) can be induced to express retinal pigment epithelial (RPE) cell markers in vitro and can home to the site of RPE damage after mobilization and express markers of RPE lineage in vivo.
METHODS. Adult RPE cells were cocultured with green fluorescence protein (GFP)-labeled stem cell antigen-1 positive (Sca-1+) BMCs for 1, 2, and 3 weeks. Cell morphology and expression of RPE-specific markers and markers for other retinal cell types were studied. Using an animal model of sodium iodate (NaIO3)-induced RPE degeneration, BMCs were mobilized into the peripheral circulation by granulocyte-colony stimulating factor, flt3 ligand, or both. Immunocytochemistry was used to identify and characterize BMCs in the subretinal space in C57BL/6 wild-type (wt) mice and GFP chimeric mice.
RESULTS. In vitro, BMCs changed from round to flattened, polygonal cells and expressed cytokeratin, RPE65, and microphthalmia transcription factor (MITF) when cocultured in direct cell–cell contact with RPE. In vivo, BMCs were identified in the subretinal space as Sca-1+ or c-kit+ cells. They were also double labeled for GFP and RPE65 or MITF. These cells formed a monolayer on the Bruch membrane in focal areas of RPE damage.
CONCLUSIONS. Thus, it appears that BMCs, when mobilized into the peripheral circulation, can home to focal areas of RPE damage and express cell markers of RPE lineage. The use of endogenous BMCs to replace damaged retinal tissue opens new possibilities for cell replacement therapy in ophthalmology.
| HOME | HELP | FEEDBACK | SUBSCRIPTIONS | ARCHIVE | SEARCH | TABLE OF CONTENTS |