Fig. 2

Tau peptides quantified by PRM correlate to Tau measurements by immunoassay. a Three Tau peptides mapping to the mid-domain (P1 and P2) or the N-terminal acidic region (P3) were quantified by label-free PRM in the replication cohort. The normalized peak area measurements for P1, P2, and P3 were compared with total Tau level measurements by immunoassay in a subset of samples (n = 67). b P1, mapping to residues 195-209 of Tau, showed strong correlation (cor = 0.89, p = 3.16e−23) with Tau levels by Luminex immunoassays. c Label free peak area for Tau P2, mapping to residues 156–163, was also significantly correlated to Tau immunoassay (cor = 0.92, p = 2.11e−28). d Label-free peak area of P3, mapping to residues 25–44, also correlated to immunoassay measurements (cor = 0.78, p = 9.73e−15)