A simplified and sensitive immunoprecipitation mass spectrometry protocol for the analysis of amyloid-beta peptides in brain tissue

B C Richard; T A Bayer; S Bergström Lind; G Shevchenko; J Bergquist

doi:10.1016/j.clinms.2019.07.001

A simplified and sensitive immunoprecipitation mass spectrometry protocol for the analysis of amyloid-beta peptides in brain tissue

Clin Mass Spectrom. 2019 Jul 19:14 Pt B:83-88. doi: 10.1016/j.clinms.2019.07.001. eCollection 2019 Nov.

Authors

B C Richard^{1

2}, T A Bayer^{1

2}, S Bergström Lind³, G Shevchenko³, J Bergquist³

Affiliations

¹ Department of Neuropathology - AG Heppner, Charité - Universitätsmedizin Berlin, Campus Mitte, Charitäplatz 1, DE-10117 Berlin, Germany.
² Department of Psychiatry and Psychotherapy, Universitätsmedizin Göttingen, von Siebold Strasse 5, DE-37075 Göttingen, Germany.
³ Analytical Chemistry and Neurochemistry, Department of Chemistry - BMC, Uppsala University, Box 599, SE-75124 Uppsala, Sweden.

Abstract

In the field of Alzheimer's disease, there is an urgent need for novel analytical tools to identify disease-specific biomarkers and to evaluate therapeutics. Preclinical trials commonly employ amyloid beta (Aβ) peptide signatures as a read-out. In this paper, we report a simplified and detailed protocol for robust immunoprecipitation of Aβ in brain tissue prior to mass spectrometric detection exemplified by a study using transgenic mice. The established method employed murine monoclonal and rabbit polyclonal antibodies and was capable of yielding well-reproducible peaks of high intensity with low background signal intensities corresponding to various Aβ forms.

Keywords: AD, Alzheimer’s disease; APP, amyloid precursor protein; Amyloid beta peptides; Aβ, amyloid beta; BSA, bovine serum albumine; Brain; FA, formic acid; IP, Immunoprecipitation; Immunoprecipitation; MALDI-TOF MS; MALDI-TOF MS, matrix-assisted-laser-desorption time-of-flight mass spectrometry; MS, mass spectrometry; PBS, phosphate buffered saline; S/N, signal-to-noice ratio; SA, sinapinic acid; VD, volume of Dynabeads suspension; Wt, wild type.