In spin-down assay, G-actin fractions of controls displayed two closely spaced bands of actin in SDS-PAGE; while in AD and DS, only the upper band of the doublet was present.
Urea-SDS-PAGE followed by Western blotting revealed that all Aβ peptide variants are reduced in bacterial meningitis, whereas in Alzheimer's disease, only Aβ<sub>1-42</sub> is reduced.These results have two implications.
To circumvent this issue, we analyzed by SDS-PAGE large fragments of sAβPP and their variants in the CSF from Alzheimer's disease (AD; n = 20) and control (n = 20) subjects, probing with specific antibodies against particular domains.