Fig. 6
mAb158 F(ab’)2 fragments reduce Aβ accumulation in astrocytes. To confirm that the effect of mAb158 on Aβ42 protofibril degradation was a Fcγ receptor-independent mechanism, cell cultures were exposed to the F(ab’)2 fragments of mAb158 together with the Aβ42 protofibrils. Astrocytes in co-cultures exposed to Aβ42 protofibrils accumulated Aβ (a) but not when co-treated with mAb158 (b). In cultures treated with F(ab’)2 mAb158 + Aβ42 protofibrils, the accumulation of Aβ was reduced, almost to the same level as for mAb158 (c). The 555-intensity/number of living cells (d), 555-intensity/number of Aβ inclusions (e), and total 555-stained area of Aβ inclusions (f) were all significantly reduced in co-cultures treated with Aβ42 protofibril + mAb158 and Aβ42 protofibril + mAb158 F(ab’)2 fragments, as compared to Aβ42 protofibril exposed co-cultures. GFAP (green), DAPI (blue), and Aβ (red). Scale bar 20 μm. The experiments were performed in triplicates with independent cell cultures, and 10 images/experiment were analyzed using Mann–Whitney U test (***P < 0.001)