Abstract

P 275

Proteomic analysis of tears in patients with dry and exsudative age-related macular degeneration

Christina Kramann, Nils Böhm, Bernhard Stoffelns, Norbert Pfeiffer, Franz H. Grus
Universitäts-Augenklinik Mainz

Objective
Previous studies could reveal possible AMD biomarker e.g. Factor H in genetic and proteomic analyses in sera of AMD patients. The aim of this study was to perform a proteomic analysis in tear fluid of patients with dry and exsudative AMD (age-related macular degeneration) in order to detect biomarkers that might differentiate better between the groups than the analyses based on sera.
Methods
90 patients, subdivided into healthy subjects (n=23), patients with dry AMD  (n=34) and 33 patients with exsudative AMD were examined. Tears were collected on Schirmer strips, eluted, and spotted on a MALDI-TOF target using a robotic laboratory automation station. Additionally all samples were purified using C 18 coated magnetic nano-beads. These steps were carried out on a robot station, too. Samples were analyzed using MALDI-TOF/TOF. For workup and analysis raw data were transferred to a in-house developed software. Detected peaks were clustered and statistical analysis incl. biomarker detection was performed using various algorithms like multivariate statistics and artificial neural networks.
Results
All subjects showed different and complex protein patterns. Several protein peaks showed significant up- and down- regulations in the dry and exsudative AMD groups compared to the control group. The multivariate statistical analysis found significant differences (p<0.05) in the protein profiles compared to the control group, e.g. the biomarkers in the low molecular weight region at 1630 Da, 1807 Da, 1687 Da and 4964 Da (p<0.05 in the dry AMD and exsudative AMD group compared to controls).
Conclusions
Our study demonstrates that complex changes in tear protein patterns can be found in patients with exsudative and dry AMD which can differentiate between both groups and could lead to new innovative treatments.

Copyright: 2009 Porstmann Kongresse GmbH. All rights reserved. Impressum, Disclaimer.