Assessments based on enzyme-linked immunosorbent assay of bound Aβ_1-42-biotin does not distinguish between elderly high-pathology controls and elderly subjects with mild ADD.

<p>(<b>A</b>) There was no difference between groups in the levels of overall Aβ_1-42-biotin recovered from dissociated tissue, as measured using an indirect ELISA which only detects biotinylated Aβ (not significant [n.s.] by Mann–Whitney U test). Data expressed as picograms Aβ per nanogram of total measurable protein. (<b>B</b>) The ratio of the amount of Aβ_1-42-biotin to the amount of Aβ_1-x as measured by sandwich ELISA was not different between groups (not significant [n.s.] by Mann–Whitney U test). (<b>C</b>) The ratio of Aβ Aβ_1-42-biotin as measured by sandwich ELISA to the percent gray matter plaque coverage did not differ between groups (not significant [n.s.] by Mann–Whitney U test). (D) There was no difference between groups in the levels of overall Aβ_1-x recovered from dissociated tissue, as measured using an sandwich ELISA (not significant [n.s.] by Mann–Whitney U test).