Abstract
Abstract: :
Purpose: To examine the expression of CD45RA, a specific isoform of leukocyte common antigen which induces B-cell and T-cell development and maturation after antigenic activation, on injured retinal ganglion cells (RGCs) in an experimental glaucoma model and following optic nerve transection in adult Sprague-Dawley rats. Methods: In the experimental glaucoma model, the limbal and the episcleral veins of the right eyes of the animals were photocoagulated by laser while their left eyes served as an internal control. Animals were then sacrificed 14 days later. In the second group of animals, optic nerve was transected at about 1.5 mm from the optic disc. The post-operative survival period was 7 or 14 days. The expression of CD45RA was assessed by immunohistochemistry. Results: Expression of CD45RA was not found on RGCs of normal eyes. Two weeks after laser photocoagulation, RGCs of the glaucomatous eye expressed high level of CD45RA while that of the contralateral eye expressed low level of the antigen. In the optic nerve transection model, RGCs of the injured eyes, enucleated at day 7 and day 14 after the injury, also expressed high level of CD45RA. Conclusions: CD45RA was expressed on injured RGCs following experimental glaucoma and optic nerve transection. Since CD45RA is involved in the maturation and activation of lymphocytes, induced expression of this antigen in CNS may represent one of the communicating path between the injured neurons and the immune system.
Keywords: ganglion cells • stress response • immunomodulation/immunoregulation