MAPT and Alzheimer disease: In CN subjects, the CSF proteins showed significant correlations with AD markers as follows: Man-Tf vs. p-tau (rs = 0.53), tau (rs = 0.56), Aβ40 (rs = 0.73), and Aβ42 (rs = 0.52); GlcNAc-Tf vs. p-tau (rs = 0.77), tau (rs = 0.79), and Aβ40 (rs = 0.76); L-PGDS vs. p-tau (rs = 0.91), tau (rs = 0.87), and Aβ40 (rs = 0.76).