Abstract
Purpose: :
Previous studies have been able to show specific autoantibody profiles against ocular antigens in the serum of patients suffering from different types of glaucoma such as primary open angle glaucoma (POAG) or normal tension glaucoma (NTG). The purpose of this study was to analyze the effect of sera from different glaucoma patients on the protein expression profiles of neuroretinal cells (R28).
Methods: :
R28 cells were incubated with medium containing 10% serum either from POAG or NTG patients, serum from healthy subjects as well as POAG serum after antibody removal. Each cell group then was incubated with elevated pressure of 15000pa or normal pressure for 48h at 37°C. After cell lysis the protein profiles were measured with Seldi-Tof MS (Biorad, USA) as well as Maldi Tof-Tof MS (Bruker Daltonics, Billerica). To find the most significant differences the protein profiles were analyzed with multivariate statistics.
Results: :
The protein profiles of the cells counted more than 400 protein and peptide cluster. An analysis of discriminance calculated several highly significant biomarker in the cells incubated with POAG serum, e.g. at 9192Da (p<0.001) or at 12390Da (p<0.001). The effect of the POAG serum was significantly decreased after antibody removal (p<0.03). Highly significant biomarker could also be detected in the cells incubated with NTG, e.g. at 29610Da (p<0.03). When comparing the cells incubated with POAG or NTG serum to cells incubated with healthy serum we could detect some biomarker which reacted similar in both groups, e.g. at 10239Da (p<0.001), as well as biomarker that reacted differently in both groups, e.g. at 22174 (p<0.011; Mean +/- SE in healthy cells: 253U +/- 45; Mean +/- SE in NTG cells: 132U +/-21).
Conclusions: :
Keeping previous studies in mind showing specific antibody profiles in patients with different glaucoma types, we concluded that the different cell reactions toward POAG or NTG serum underline the theory that an auto-immunologic component plays a significant role in the pathogenesis of the disease. This conclusion is strengthened by the fact that the cells reacted significantly different after antibody removal.
Keywords: ganglion cells • proteomics