Immune markers in Age related macular degeneration

Abstract

Abstract: : Purpose: There is increasing evidence that the immune system is involved in the pathogenesis of age–related macular degeneration (AMD). Our intention is to identify auto–antibodies against retinal tissue in patients with bilateral drusen (early disease) and exudative AMD with choroidal neovascularisation (CNV) using indirect immunohistochemistry. The phenotype was characterized according to staining pattern and then correlated with the clinical features graded according to the International classification and grading system of age–related maculopathy. Method: Patients with bilateral drusen (n=55), and with CNV (n=50) were recruited from the Macular Clinic in addition to age–matched normal controls (n=13). The sera were analyzed for anti–retinal autoantibodies on murine (balb/c) retinal sections using indirect immunocytohistochemistry. Results: The results show that sera of patients with bilateral drusen have a significantly (p=0.02) higher titre of auto–antibodies to the inner and outer (74.55%) nuclei layers of the retina in comparison to CNV (67%) and control groups (23.08%) indicating significant evidence of involvement of the immune process in the early stage of AMD. Subsequent statistical analysis of the drusen group showed significant progressive staining (p=0.0009) in the nuclei layers from early to late stages of ARM. Conclusion: Anti–retinal autoantibodies are present in patients with bilateral drusen and exudative AMD. These autoantibodies may not simply a reactive response to the CNV but might play a significant role in the pathogenesis of AMD. The role of these autoantibodies in pathogenesis and as a prognostic factor for exudative AMD warrants further investigation.

Keywords: age–related macular degeneration • immunohistochemistry • retina