Three-Dimensional Study of Alzheimer's Disease Hallmarks Using the iDISCO Clearing Method

Area of Science:

• Neuroscience
• Biomedical Imaging
• Pathology

Background:

• Amyloidosis is implicated in over 100 diseases, notably Alzheimer's disease (AD).
• Understanding amyloid plaque formation and structure is crucial for disease progression insights.

Purpose of the Study:

• To visualize and quantify amyloid plaque formation in 3D within intact mouse and human brains.
• To explore the micro-environment of amyloid plaques, including tau, microglia, and vasculature.

Main Methods:

• Utilized the iDISCO method: targeted molecular labeling, tissue clearing, and light-sheet microscopy.
• Applied volume imaging with automated detection and mapping for plaque quantification.
• Methodology adapted for analysis of frozen human brain samples.

Main Results:

• Successfully visualized 3D amyloid plaque formation in intact AD mouse brains up to 27 months old.
• Identified greater 3D complexity and large three-dimensional amyloid patterns (TAPs) in human brain tissues.
• Demonstrated precise and fast quantification of plaques throughout the entire intact mouse brain.

Conclusions:

• The iDISCO method provides powerful 3D visualization of amyloid plaques and their micro-environment.
• Discovery of large TAPs in human brains suggests novel structural aspects of amyloidosis.
• This approach has significant scientific and medical implications for studying diseases like Alzheimer's.