Figure 4

Stability of the PrP226* fragment in brain homogenates. (A) 10% brain homogenates from 6 non-CJD and 6 sCJD patients were split into 2 aliquots, one of each was left at RT overnight and the other was refrozen immediately. Samples were measured on the following day by V5B2/EM20-b sandwich ELISA. Absorbance values of two non-CJD samples were not higher than the background and were therefore not considered. The percentage of the PrP226* signal measured in samples left at RT is calculated relatively to the signal of frozen samples. (B) Recombinant human PrP226* (recPrP226*) was spiked into a non-CJD brain homogenate and left for 30 min, 1 h or 2 h at 4°C (lines 1–3), at RT (lines 4–6) or at 37°C (lines 7–9). RecPrP226* was added as a control (line 10). V5B2 (5 μg/ml) was used as detecting antibody.