Figure 2.

Binding profiling of five Affibody molecules to different Aβ aggregates, analyzed by ELISA. (a) Aβ₄₂wt and Aβ₄₂cc aggregates (50 nM assay concentration), bound to Affibody molecules, were detected by 6E10-HRP. 6E10²¹ recognizes the N-terminus of Aβ. As expected, all five Affibody molecules show binding to Aβ₄₂cc protofibrils. The Affibody molecule Z_{Aβ42cc_1} also binds to Aβ₄₂wt protofibrils. No binding could be observed to either wild type monomer or fibrils. (b) Same as in (a), except that the assay concentration of Aβ₄₂ was 1 µM and mAb1C3 was used for detection (weakly specific for protofibrils²¹). The binding profile has the same pattern as in (a) for protofibrils (both wt and cc) and Aβ₄₂wt fibrils, but with a higher background for Aβ₄₂wt protofibrils. (a,b) Two controls involve replacing the Affibody molecule with either an irrelevant Affibody molecule (Z_{Taq_2}) or by PBS-T. In a third control experiment PBS-T was added instead of Aβ-specific antibody (6E10 or mAb1C3). Values are means of duplicate experiments.