The INNOTEST hTAU Ag is a solid-phase enzyme immunoassay for the quantitative determination of Tau protein, phosphorylated and non-phosphorylated, in human cerebrospinal fluid (CSF). This assay measures the biomarker called total Tau, including the six isoforms (352 to 441 amino acids) from the brain.
The combined use of CSF-Tau and CSF-β-amyloid_(1-42) marker concentrations allows differentiation between Alzheimer's disease (AD) and normal aging or other neurological diseases such as depression . As AD diagnosis marker, the results obtained with this assay should be interpreted in combination with other clinical and diagnostic information (e.g. using results obtained with the INNOTEST β-AMYLOID_(1-42) and the INNOTEST PHOSPHO-TAU_(181P)). The discrimination of AD from non-AD types of dementia such as dementia with Lewy Bodies may be further improved using the quantification of CSF-phospho-Tau₍₁₈₁₎ .
AD, the most common form of dementia, is a neurodegenerative disorder histologically characterized by the accumulation of intracellular neurofibrillary tangles and extracellular amyloid plaques throughout the cortical and limbic brain regions.The ultrastructure of neurofibrillary tangles is made up of paired helical filaments composed mainly of abnormally hyperphosphorylated Tau protein (Phospho-Tau). The major components of the amyloid deposits are the 40- and 42-amino acid-long β-amyloid peptides, which are derived from integral membrane-bound amyloid precursor protein.