Visualization of Amyloid-Beta Peptides in Human Cortical Brain Slices

Abstract

Source: Ikegawa, M. et al. Visualization of Amyloid β Deposits in the Human Brain with Matrix-assisted Laser Desorption/Ionization Imaging Mass Spectrometry. J. Vis. Exp. (2019)

The video demonstrates a procedure for preparing human cortical brain slices from Alzheimer's disease patients for analyzing the deposition of amyloid-beta (Aβ) peptides using Matrix-assisted Laser Desorption/Ionization Imaging Mass Spectrometry (MALDI-IMS). The steps include preparing the slides, treating the tissue to enhance ionization, and analyzing the spatial distribution of amyloid-beta peptides.

Protocol

All procedures involving sample collection have been performed in accordance with the institute's IRB guidelines.  

1. Preparation of Tissue Sections for Imaging Mass Spectrometry (IMS)

1. Processing tissue specimen of a human autopsied brain
   NOTE: Ensure that the sample preparation step for IMS preserves the original state of the tissue. Avoid contamination and post-mortem changes. The following step is crucial.
   1. Obtain human cortical specimens for IMS from brains that were removed, processed, and stored at -80 °C within 8 h postmortem.....

Materials

List of materials used in this article

Name	Company	Catalog Number	Comments
Cryostat	Leica Microsystems, Wetzlar, Germany	CM1950
Indium tin oxide (ITO)-coated microscope glass slide	Bruker Daltonics	#237001
Blade (disposable)	Leica Microsystems, Wetzlar, Germany	#117394
O.C.T. Compound	Leica Microsystems, Wetzlar, Germany	FSC 22 Blue
Scanner	EPSON	GT-980
Air-Brush	GSI Creos	PS274
Compressor	MRHOBBY	Mr.Linear compressor L5
Ultrasonic sprayer	Bruker Daltonics	ImagePrep
Automatic sprayer	HTX Technologies	TM Sprayer
Confocal-laser-scanning- microscope	Carl Zeiss Inc.	LSM 700
Ultra high speed MALDI instrument	Bruker Daltonics	rapifleX MALDI Tissuetyper
MALDI control software	Bruker Daltonics	FlexControl 3.8
Molecular histology software	SCiLS, Bremen, Germany	SciLS Lab 2016a
Sinapinic acid (SA)	Nacalai tesque	30494-91
Alpha-Cyano-4-hydroxyl-cinnamic acid (CHCA)	Wako	037-19261
Calibration standard	Bruker Daltonics