Affinity of moAbs to thermal-modified Aβ40 [13]. Enzyme-linked immunosorbent assay (ELISA) measurements of antibody affinity towards temperature-modified Aβ40 were performed. The reactivity of four antibodies as mentioned in Figure 2 (4G8, 6F/3D, anti-1–7, anti-5–10) to samples of Aβ40 that had been exposed to temperatures over the range 36–42°C at 1°C interval and at 20°C as a control, was monitored by ELISA. Statistical comparisons were performed with unpaired -tests. The values are means ± SEM. Statistically significant differences versus 6F/3D were determined at each temperature (). For both anti-5–10 and 1–7 antibodies, the reactivity was constant through the whole temperature range from 35°C to 42°C, and no temperature-dependent difference was detected. The monoclonal antibody 6F/3D showed temperature-dependent reactivity, and the reactivity was bimodal, when the modified temperature was increased from 36 to 38°C and from 38 to 41°C. On the other hand, 4G8 showed temperature-dependent reactivity, when the temperature increased from 36 to 40°C. Thus, the 9–14 and 17–21 amino acid residues within Aβ40 peptide were sensitive to temperature changes.