Fig. 6: Evolution of intraneuronal β-amyloid accretion and distribution in PANTHOS neurons in brains of AD mouse models.

a, IHF co-labeling of 2.7-month-old male 5xFAD/TRGL mouse brain neurons with JRF/AβN/25 monoclonal antibody against APP-βCTF/Aβ. Scale bar, 10 μm. b, IHF labeling of Aβ (4G8) and DAPI stain. Perinuclear intraneuronal Aβ accumulation surrounding a visible DAPI-positive nucleus within a PANTHOS neuron. Inset depicts Aβ in a bleb of the PANTHOS neuron. Scale bar, 10 μm. c, Immunofluorescence staining of a DAPI-labeled PANTHOS neuron using 4G8 antibody followed by fluorescence intensity analysis. Perinuclear Aβ accumulates within a PANTHOS neuron. The white line in the merged image indicates the scan path through the PANTHOS neuron from which fluorescence intensity is determined spatially for each fluorophore. Scale bar, 10 μm. d, Representative Aβ IEM (3D6) image demonstrates extensive AV-filled blebbing of the PM in a PANTHOS neuron (colorized light pink) and, by comparison, two profiles (blue coloration) tentatively identified as DNs in a 5-month-old 5xFAD/TRGL mouse brain. Scale bar, 10 μm. Box i depicts Aβ immunoreactive AVs in the bleb. Box ii depicts overlap of Aβ immunoreactivity with the central nuclear area that also displays the electron-dense network of radiating membrane-bound tubular extensions, which are strongly Aβ immunoreactive. Yellow arrows indicate AVs incorporated into the central amyloid-positive network. Scale bar, 500 nm. e, Representative amyloid (3D6) IEM image. Light-blue arrowheads denote vesicle and amyloid bundle contact sites. a–d, The experiment was repeated three times independently with similar results. Scale bar, 1 μm. See also Extended Data Fig. 6. PM, plasma membrane.