MAPT and Alzheimer disease: In one study, assessment of the concentrations of various metalloproteinases and AD biomarkers of Aβ1-42, T-tau, and P-tau181, which were assayed simultaneously using luminex ELISA technology in the CSF, revealed significant decreases in MMP-2 and MMP-3 levels in the CSF in the samples with significantly reduced Aβ levels [45].