MAPT and Alzheimer disease: pT231 tau reached mean values of 1793 ± 490.3 U/mg brain weight in the detergent-soluble brain lysate fractions of 3xTg-AD control mice, 1454 ± 390.6 U/mg in Aβ42 peptide-immunized mice, and 1199 ± 221.5 U/mg in DNA Aβ42 trimer-immunized mice.