Fig. 5

Quantification of intracellular Aβ uptake by fetal rat astrocytes. Astrocytes were plated in a 24-well plate at 20,000 cells per well and cultured for 2 days at 37 ℃. Prior to cellular treatment, 6H4 antibody fragments (Fabs) and 3D6 Fabs were incubated with amyloid β (Aβ)42 to form Fab-antigen complexes at a molar ratio of 1:1. The astrocytes were then incubated for 1 and 2 h with Aβ42s alone (white bar), 6H4 Fab-Aβ42 complexes (black bar), or 3D6 Fab-Aβ42 complexes (horizontal striped bar). Intracellular Aβ42 was quantified using an Aβ amyloid42 enzyme-linked immunosorbent assay kit. A 1-h incubation with the 3D6 Fabs-Aβ42 complexes yielded significantly more (4.7-fold) Aβ42 in the astrocytes than as compared with that obtained by incubation with Aβ alone. Similarly, a 2-h incubation with 6H4 Fab-Aβ42 complexes yielded significantly more (2.3-fold) Aβ42 in the astrocytes as compared with that obtained by incubation with Aβ alone. Statistical evaluations were performed using a one-way analysis of variance with a Tukey’s post-hoc test. *p < 0.05