M. Kraszpulski et al., PITFALLS IN THE QUANTITATIVE ESTIMATION OF BETA-AMYLOID IMMUNOREACTIVITY IN HUMAN BRAIN-TISSUE, HISTOCHEM C, 110(4), 1998, pp. 439-445
The duration of formic acid (FA) pretreatment clearly influences the e
xtent of beta-amyloid immunoreactivity in brain tissue and consequentl
y also the results of quantitative analysis. All of the parameters stu
died (area fraction, density, and mean size of beta-amyloid deposits)
significantly increased with pretreatment of up to 6 h with beta-amylo
id antibody obtained from Dako. Longer exposure to FA only marginally
increased the mean size of the single deposits, whereas the area fract
ion and the density of beta-amyloid deposits slightly decreased. Optim
al 6-h pretreatment (or even longer) did not reveal any beta-amyloid a
ggregates in those cases where none was seen with shorter durations of
FA pretreatment. Similar results were obtained with beta-amyloid anti
body 4G8 obtained from Senetek, whereas beta-amyloid antibody 6E10 was
shown to be less dependent upon FA pretreatment. In conclusion, we re
commend that the FA pretreatment time should be studied and optimized
for each antibody used and always be described when the quantitative a
nalysis of beta-amyloid load is reported.