Fig. 4
From: Dual-probe fluorescence spectroscopy for sensitive quantitation of Alzheimer’s amyloid pathology
Different β-sheet-rich assemblies were revealed by widely varying emission signatures using the dual-probe approach. (A) Staining of human AD brain sections resulted in remarkable spectral heterogeneity of amyloid plaques (yellow and green asterisks) and tangles (arrows), shown as truecolor spectral images. (B) Formic acid treatment disrupted the β sheet structures thereby eliminating BSB and MCAAD-3 signal. (C) Immunohistochemistry for anti-amyloid β (4G8) and anti-tau (K9JA) confirmed the identity of the proteins stained with the amyloid dyes (same field of view in A-C). (D) Visually different amyloid β plaques and tangles in panel A exhibited striking differences in their emission spectra. Amyloid β deposits that appeared similar using antibody labeling (E1) had distinct emission signatures with the dual-probe staining method (E2), also reflected by distinct peaks on the phasor plot (F). Scale bars: 50 μm