Abstract
Abstract: :
Purpose:Crystallins were identified in our recent proteomic analysis of drusen from age–related macular degeneration (AMD) donor eyes. This study was conducted to define the localization of crystallins in drusen, Bruch’s membrane and choroid of AMD tissues and to compare this distribution with that in non–AMD age–matched control tissues. Methods: Human eyes with AMD and age–matched non–AMD control eyes were used (AMD: 8 eyes from 66–83 year old donors, age–matched controls: 5 eyes from 76–88 year old donors). Proteomic analysis and Western blots of Bruch’s membrane/choroid complex were performed to identify crystallins. Frozen tissues embedded in OCT were prepared for immunohistochemistry. Crystallin antibodies were used for light microscopy employing the ABC method. Results: Drusen and Bruch’s membrane from AMD tissues showed greater immunoreactivity for αA and αB crystallins than did control tissues. Western blots also showed more intense αA and αB crystallin signals from AMD than were present in control tissues. ßB1 crystallin, in contrast, showed similar immunoreactivity in both AMD and control eyes. Conclusions: αA and αB crystallins are more abundant in drusen and Bruch’s membrane of AMD compared to age–matched controls. This study suggests that accumulation of αA and αB crystallins in drusen and Bruch’s membrane may be response to stress and is related to the progression of AMD. Supported by NIH National Eye Institute grants EY014239, EY014240 and the Foundation Fighting Blindness.
Keywords: drusen • Bruch's membrane • crystallins