Thiazine red staining is a reliable and rapid pos-mortem diagnostic tool for Alzheimer's disease

Abstract

We have used a variety of tau immunological markers combined with the dye Thiazin red (1), an accurate marker to differentiate the fibrilar from the nonfibrillar state of both amyloid-β and tau in Alzheimer´s disease (AD). In this study, we used TR as a potential diagnostic marker of AD in unfixed brain tissue and tissue touch imprint. Control experiments included the use of thioflavin-S staining, fixed tissue, and some double-labeled material with TR and selected tau markers, including, Tau-C3, and 423. Our observation indicate that TR retains its strong affinity for both tangles and plaques neuritic plaques in frozen unfixed temporal cortex then thawed prior to tissue touch imprint. This indicates the potential for TR as a diagnostic tool for the rapid postmortem diagnosis of AD neuropathology. chemical fixation is not necessarily required for tau immunoreactivity on histological sections.