Quantitative analysis of differentially expressed brain proteins in the EAE-model for multiple sclerosis

Abstract

The aim of this study is the identification of MS-related proteins (and possible candidate-biomarkers) through comparison by DIGE of the protein profiles in the brain stem of EAE animals and healthy controls in different stages of the disease. DIGE simultaneously separates two protein samples and an internal standard in a single two-dimensional gel and requires fluorescent protein labelling. Labelled samples are multiplexed which reduces gel-in-gel-variability. Inclusion of an internal standard (sum of all samples) allows for proven quantitative analysis of protein expression profiles. Using this approach, we analysed "blood-free" brain stems of 12 Lewis-rats (feminine, 7 weeks old), 9 of which were immunised (MBP in combination with CFA) to induce EAE, and 3 of which were controls. Four groups were compared (induction of disease, top, recovery, and control) with 3 biological replicas per condition. Preliminary analysis showed differential proteins over the four conditions. Moreover, different types of expression profiles were observed. An in-depth analysis of the DIGE results in combination with protein identification by mass spectrometry is undertaken. Due to sample collection on different stages after immunization, expression dynamics can be examined in order to bring a better understanding of this disease.

Publication appears at doi: 10.1016/j.jneuroim.2008.04.005