Figure 1.

Enhancement of formic acid (FA)–mediated amyloid β peptide (Aβ) antigen retrieval. Serial brain tissue sections from a 74-year-old male patient with Alzheimer disease (A–D) and from a 13-month-old amyloid precursor protein–Swedish/London (APP-SL) mouse of line 7–5 (E–H) were immunostained with anti-Aβ antibody 4702 following pretreatment by FA alone (FA) (A, E); combination of digestion with proteinase K and FA (PK/FA) (B, F); combination of autoclave heating in EDTA buffer and FA (AC/FA) (C, G); and triple combination of digestion with proteinase K, autoclave heating in EDTA buffer, and FA (PK/AC/FA) (D, H). Pictures (A–D) are from the temporal cortex. Scale bar = 200 µm (A–H).