FIGURE 3.

PT, C1r and C1s inhibit the aggregation of Aβ^1–42 to form amyloid, but not the amorphous aggregation of CS. (a–c) Aβ^1–42 (10 μM) was supplemented with ThioT (20 μM) and incubated for 60 hr in the absence or presence of 1 μM SOD (a non‐chaperone control protein) or CLU (a chaperone control protein). Aggregation reactions were also supplemented or not with either 1 μM or 2 μM of (a) PT, (b) C1r, or (c) C1s. In all cases, the molar ratio of Aβ^1–42:test protein is indicated in the respective keys. Amyloid formation was monitored by measuring ThioT fluorescence. Mean ThioT fluorescence values (in arbitrary fluorescence units, AFU) ± SEM (n = 3) are plotted In (a–c), in some cases, the error bars are too small to be visible. (d, e) Endpoint absorbance values for experiments in which 5 μM CS was incubated for 8 hr in the presence or absence of 1 μM of SOD or CLU, or 5 μM of (d) PT or (e) C1r or C1s. Amorphous protein aggregation was monitored as turbidity measured as absorbance at 360 nm (A³⁶⁰). Mean endpoint absorbance values (i.e., at 8 hr) ± SEM (n = 3) are plotted. Each result is representative of two independent experiments. In (d) and (e), the asterisks indicate significant differences in A³⁶⁰ between the CS alone and +CLU treatments (Students t‐test, p < .01); other differences are not significant