MAPT and Alzheimer disease: Using AT180 and AT270 as capturing antibodies, and HT7 and AT120 as detection antibodies, concentrations of tau phosphorylated at threonine 181 (p-tau181) and threonine 231 (p-tau231) were found to be increased approximately 3.5-fold in the CSF of AD patients compared to controls (AD n = 44; average p-tau concentration 2230 ± 930 pg/mL vs. controls n = 31 average p-tau concentration 640 ± 320 pg/mL).