Abstract
Abstract: :
Purpose: To evaluate if transplanted bone marrow stromal cells (BMSCs) to the glaucomatous eyes could be integrated into the host retina and/or optic nerve and could differentiate as neuron or glia. Methods: Glaucoma was induced in the right eye of adult Wister rats by ligating episcleral veins. The left eye was sham operated and used as a control. Intraocular pressure (IOP) was measured once a week. The GFP–expressing bone marrow stromal cells(GFP–BMSCs) were injected into the vitreous body of both the control and the glaucomatous eyes at various stages. Rats were sacrificed between 1week and 2 months after GFP–BMSCs injection, and retina and optic nerve were analyzed by light microscopy and immunohistochemistry with neuron– and glia– specific markers. Results: After ligation of episcleral veins, rats developed significant elevation of IOP in operated eyes(27.9 ± 2.5 mmHg), and no elevation of IOP in sham operated eyes(21.0 ± 1.9 mmHg). Glaucomatous eyes showed the decrease of retinal ganglion cell number and significant excavation of optic disc. GFP–BMSCs were integrated into the ganglion cell layer and nerve fiber layer of host retina at 1 week after transplantation. At 4 weeks after transplantation, Nestin, a marker for neural stem cell, or Glutamine synthetase, a marker for Müller cell, were observed to be expressed by GFP positive transplanted cells. The increase of thickness of nerve fiber layer was also observed. Conclusions: Ligation of episcleral veins represents a useful and an efficient model of experimental glaucoma in rats. Transplanted BMSCs could survive and appear to differentiate into neuron and glia in the glaucoma model. This study suggests that transplanted BMSCs may be worthy as a neuroprotective agent to treat chronic open–angle glaucoma
Keywords: optic disc • transplantation • microscopy: light/fluorescence/immunohistochemistry