MAPT and Alzheimer disease: In MCI, CSF protein levels also correlated with AD markers as follows: Man-Tf vs. p-tau (rs = 0.68), tau (rs = 0.50), Aβ40 (rs = 0.44); GlcNAc-Tf vs. p-tau (rs = 0.61), tau (rs = 0.51), and Aβ40 (rs = 0.42); L-PGDS vs. p-tau (rs = 0.46) and tau (rs = 0.37).