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

Abstract

Summary Amyloidosis is a major problem in over one hundred diseases including Alzheimer's disease (AD). Using the iDISCO visualization method involving targeted molecular labeling, tissue clearing and light-sheet microscopy, we studied plaque formation in the intact AD mouse brain and up to twenty-seven months of age. We visualized amyloid plaques in 3D together with tau, microglia and vasculature. Volume imaging coupled to automated detection and mapping enables precise and fast quantification of plaques within the entire intact mouse brain. The present methodology is also applicable to analysis of frozen human brain samples without specialized preservation. Remarkably, amyloid plaques in human tissues showed greater three-dimensional complexity and surprisingly large three-dimensional amyloid patterns or TAPs. The ability to visualize amyloid in 3D, especially in the context of their micro-environment, while simultaneously analyzing two other markers, and the discovery of large TAPs, may have potentially important scientific and medical implications.

C-Eci: A Cubic-Eci Combined Clearing Method For 3D Follicular Content Analysis In The Fish Ovary

“…and that 50°C-pH7 staining conditions significantly improve the MG staining. We 23 cannot exclude that similar results could also be obtained with the widely used 1 iDISCO+ method, since this later includes a delipidation step with the organic 2 dichloromethane reagent (DCM)(Liebmann et al, 2016) (Renier et al, 2016). 3…”

“…11% for the mouse brain (Renier et al, 2016). However, a moderate shrinkage may 1 not be considered as a drawback since it can allow easier imaging of large samples 2 such as entire mice (Pan et al, 2016).…”

A beginner’s guide to tissue clearing

“…Another common disadvantage mentioned when discussing these methods is sample shrinkage, though recent improvements have either solved this issue (iDISCO+ (Renier et al, 2016)) or turned it into an advantage for specific applications that require the imaging of very large samples, like entire adult mice or young rats (uDISCO, Figure 1 (Pan et al, 2016)). Some examples of successful applications of organic solvent-based clearing include analysis of vasculature and drug delivery in tumors (BABB (Dobosz et al, 2014)), automated mapping of mouse brain activity at the cellular level (iDISCO+ (Renier et al, 2016)) and automated quantification of amyloid plaques in old mouse brains (iDISCO+ (Liebmann et al, 2016)).…”

Mapping causal pathways from genetics to neuropsychiatric disorders using genome‐wide imaging genetics: Current status and future directions

“…Tissue‐clearing approaches are also being scaled and adapted specifically for use on post‐mortem human brain tissues, providing a valuable tool for obtaining high‐resolution volumetric observations of neuropsychiatric pathologies . As an example, tissue‐cleared brains from Alzheimer's disease patients showed remarkably detailed 3‐D measurements of amyloid plaque volume, morphology, and arrangement, which varies distinctly across subjects …”

“…138 As an example, tissue-cleared brains from Alzheimer's disease patients showed remarkably detailed 3-D measurements of amyloid plaque volume, morphology, and arrangement, which varies distinctly across subjects. 139 These techniques make it possible to design an imaging genetics study of post-mortem brain structure at micrometer resolution. Such a study may be able to directly answer some of the questions posed above about the cellular basis for imaging genetics findings identified with MRI, as well as to identify new genetic influences on cellularlevel brain structure that were not observable in current association studies given the poor resolution of MRI.…”