Abstract
Purpose: :
Antibody patterns in aqueous humor and sera of glaucoma patients give hints on changes in the autoimmunity of the patients. In order to test the hypothesis that autoimmunity can be involved in the pathogenesis, we established an Experimental Autoimmune Glaucoma (EAG) animal model. The aim of this study is to find out if immunization with specific antigens (myelin basic protein and vimentin) can cause retinal ganglion cell (RGC) loss.
Methods: :
33 Lewis rats were divided into 3 groups (n=11 per group). In two groups animals were immunized with MBP or vimentin plus Freund's adjuvant and pertussis toxin. Control animals were injected with pertussis toxin and Freund's adjuvant only. All animals received booster immunizations after 4 and 8 weeks with half the dose of the initial injections and were euthanized after 10 weeks.Intraocular pressure (IOP) was measured in all animals before the study and after 2, 4, 8, and 10 weeks, and fundus pictures were taken at the same time. After the study the eyes were enucleated, fixed in 4% paraformaldehye and retinal flatmounts were stained with Kresylblue to detect RGCs. RGCs were counted with a semi-automated method.
Results: :
In both immunization groups (MBP and vimentin) significant RGC loss could be observed after 10 weeks (P<0.0002). No significant changes in IOP were observed during the course of the study, no significant IOP difference could be seen between immunized and non-immunized animals. No major changes could be observed on the fundus photos.
Conclusions: :
The EAG model is a promising new optic nerve degeneration model based on an possible autoimmune component. The role of anti-MBP antibodies in this model, which are also detected in multiple sclerosis patients, still needs to be explored further.
Keywords: retina • pathology: experimental • ganglion cells