Fig.3.

Differentiated SH-SY5Y cells show increased reactivity to IgG autoantibodies present in human serum. A, B) Confocal images of non-differentiated (A) and differentiated (B) SH-SY5Y cells treated with human serum (diluted 1:50) in medium for 24 h and then immunostained with Cy3-labeled (red) anti-human IgG antibodies and counterstained with Hoechst stain (blue) to highlight nuclei. C) Differentiated cells show increased binding of serum IgG over that of non-differentiated cells. Unexpectedly, the extent of IgG binding in cells treated with serum from an AD patient did not differ significantly from an older non-demented subject or younger control. Controls (Ctrl) were performed with omission of serum and addition of secondary antibody. Scale bar = 10 μm. ***p < 0.001. AD, Alzheimer’s disease serum; OC, old-aged matched, non-demented control; YC, younger, non-demented control.