This assay employs the quantitative sandwich enzyme immunoassay technique for the quantification of human Tau protein in cell culture supernatant, serum, cell culture extracts, plasma, cerebral spinal fluid. Standards or samples are pipetted into the wells and then add the tagged anti-Tau antibody and HRP-conjugated anti-Tau antibody mixture. Human tau protein will bind to the tagged anti-Tau antibody and HRP-conjugated anti-Tau antibody. The antibodies and Tau protein complex will then bind to the anti-tag antibody coated on the well. After washing away any unbound materials, a substrate solution (TMB) is added to the wells and color develops in proportion to the amount of human Tau protein bound in the initial step. The color development is stopped by the addition of acid and the intensity of the color is measured at a wavelength of 450nm ±2nm. The concentration of human Tau protein in the sample is then determined by comparing the O.D of samples to the standard curve. Sample Types: cell culture supernatant/extracts, serum, plasma, cerebral spinal fluid. Range: 31.25-2000 pg/ml. Sensitivity: 5.2 pg/ml. Time: 3 hours ? This gene encodes the microtubule-associated protein tau (MAPT) whose transcript undergoes complex, regulated alternative splicing, giving rise to several mRNA species. MAPT transcripts are differently expressed in the nervous system, depending on stage of neuronal maturation and neuron type. MAPT gene mutations have been associated with several neurodegenerative disorders such as Alzheimer's disease, Pick's disease, frontotemporal dementia, cortico-basal degeneration, and progressive supranuclear palsy.