Monitoring biomarkers of neurodegeneration and neuroinflammation in brain tissue by targeted proteomics
Co-Autoren: Simone Giaisi, Khader Awwad*, David Holzinger, Juliane Stein, Manuela Klee, Susanne Jausel, Kathrin Zimmer, Ana Relo, Silvana Hempel, Claudia Henn, Christina Bauder-Wenz, Beate Hilbert, Berthold Behl, Michael Schulz*, Roland Heym
AbbVie Deutschland GmbH & Co. KG, Neuroscience Discovery, Knollstrasse, 67061 Ludwigshafen
*AbbVie Deutschland GmbH & Co. KG, DMPK, Knollstrasse, 67061 Ludwigshafen
The quantification of biomarkers in brain tissue is crucial to demonstrate target engagement and pharmacodynamic effects of drug candidates in animal experiments. So far, such analyses have been primarily performed by Western Blotting or ELISA. Both methods depend on the availability of good antibodies and they are time consuming and labor intensive, especially if multiple analytes need to be measured.
We developed a multiplexed method for 8 different tissue markers (Synaptophysin, Synapsin-1, PSD95, GFAP, Tau, RGMa and BACE1) based on multiple reaction monitoring (MRM) mass spectrometry. This method is highly specific without the need for antibodies and highly efficient due to its multiplexing abilities. It requires only minute amounts of brain homogenate and is fully compatible with the procedures used for Tau and Aβ extraction.
First, we showed that the results of our MRM method are in line with classical Western Blotting and ELISA. Then, we profiled different rodent models for neurodegenerative diseases like Alzheimer's disease (e.g. APP/PS1 and rTg(tauP301L)4510 mice). We observed significant changes in biomarker levels indicating increased neurodegeneration and inflammatory processes in the brain. For example, we detected a strong age-related increase of GFAP in the brain of Tau- and APP-transgenic mice which strongly correlated with Tau and Abeta pathology. This work provides an excellent basis to analyze treatment studies for a potential reversal of biomarker changes associated with the disease process.
All authors are employees of AbbVie. The design, study conduct, and financial support for this research were provided by AbbVie. AbbVie participated in the interpretation of data, review, and approval of the publication.