The use of formic acid to embellish amyloid plaque detection in Alzheimer's disease tissues misguides key observations.

We compared our heat pretreatment method to the widely used formic acid pretreatment technique to immunohistochemically detect amyloid in control and Alzheimer's disease brain tissues. Both methods detected amyloid in plaques, neurons, ependymal cells, circulating monocytes, vascular smooth muscle and endothelial cells. Although there were no observable differences in the intensity of the amyloid labeling in these cell types using both pretreatment methods, there were considerable differences in the intensity of amyloid immunolabeling in the plaques.