P1‐164: Nitro‐proteomics to Discover Synaptosomal Biomarkers of Neuroinflammation in Alzheimer's Disease

Abstract

Background: About 30% of patients with Parkinson's disease (PD) develop a dementia in the course of the disease, called Parkinson's disease dementia (PDD). Up to date, diagnosis of PDD is merely done by clinical parameters. Recently, we described by using two dimensional gel electrophoresis (2D and 2D immunoblot) that isoforms of the serine protease inhibitor Serpin A1 are differently sialylated in the cerebrospinal fluid (CSF) of healthy individuals and PD compared to PDD. However, 2D electrophoresis is time-consuming and cannot be used as a high-throughput approach. Methods: We adopted a new nanoscale capillary isoelectric focusing (CIEF)approach for the detection of differentially sialylated Serpin A1 isoforms and compared this method to our former 2D immunoblot method. For this approach we used 50 patients with PDD, PD and non-demented controls. Results: 2D immunoblots gave mainly similar results like the CIEF approach. There was a significant difference in spot pattern between PDD, PD and CON. By CIEF we are now able to analyse up to 80 samples per day compared to 4-8 samples by our 2D immunoblot. Conclusions: The detection of different Serpin A1 isoforms by CIEF is rapid, sensitive and allows a large scale analysis of biosamples.