Abstract
Abstract: :
Purpose: Bone marrow stromal cells (BMSCs) can be experimentally induced to undergo unorthodox differentiation, possibly forming neural and endothelial cells. As such, they represent an important paradigma of postnatal non-hematopoietic stem cells, and an easy source for potential therapeutic use. Methods: BMSCs from Long-Evans rats were harvested and cultured and transduced using an adenovirus vector containing the GFP cDNA driven by a human CMV promoter. 6x105 cells in a volume of 0.5 µl were injected subretinally into eyes of 18 days old RCS rats. After 2 months the eyes were enucleated and examined using (fluorescence) light microscopy of retinal flatmount preparations. Flatmounts were examined using glial cell specific antibodies (glial fibrillary acidic protein (GFAP)) Flatmounts were also investigated by electron microscopy. As control sham operation with saline injection was performed. Results: Under the light microscope fluorescent cells were present in retinas 2 month after transplantation that expressed GFP and in addition were labeled with glial cell specific antibodies (GFAP). In semithin sections one or more layers of probably BMSCs derived cells were attached onto the host RPE. Morhologically these cells were similar to RPE cells. They contained many endocytic vesicles and parcipitated in phagocytosis of shedded disc membranes. With respect to photoreceptor cell survival we did not find significant differences between BMSC transplantation and sham operation Conclusion: BMSCs can be stably transduced by adenoviral vectors and reporter gene GFP for 2 month. BMSCs transduction with neurotrophic factors prior to subretinal transplantation may also slow down photoreceptor degeneration in this model. In addition BMSCs have the potential to restore retinal glial cells.
Keywords: 419 gene transfer/gene therapy • 472 microscopy: electron microscopy • 607 transplantation