In addition, we find that Pin1 releases this negative feedback between the pT231 and pS202/pT205 AT8 epitopes. Our findings define an additional level of molecular regulation of the PP2A phosphatase Lambrolizumab towards the phosphorylated Tau protein, whereby the interplay between kinase and phosphatase activity can potentially lead to a stable hyperphosphorylated state of Tau that characterizes AD affected neurons. Integration of a peak surface for a given resonance in each 2D spectrum during this in-spectrometer dephosphorylation reaction gives information on the kinetics of the modification of the corresponding amino acid. Because phosphorylation does not only affect the amide resonance of the modified amino acid but also that of its neighbours, the same reaction can in favourable cases be followed on different cross peaks. The A152 amide peak Ki11502 resonates for example at slightly different frequencies dependent on the phosphorylation status of T153, and the same enzymatic reaction could be followed as the decrease of the pT153 or the A152 amide cross peaks, but equally as the increase of the A152 amide correlation. Dephosphorylation of pT205 also followed an exponential trend with a similar time constant that was best monitored by the unphosphorylated T205 resonance, located in a relatively sparse region of the spectrum. Initially, no peak appears at its exact resonance position in the unphosphorylated Tau protein, but we rather observe two intermediate peaks corresponding to T205 with a further splitting due to the phosphorylation state of S199. This assignment was validated by a dephosphorylation experiment on the phospho-TauS199A/S202A double mutant, where the intermediate forms do not appear, but where we recover immediately the T205 resonance at its position in the unmodified Tau spectrum. When increasing the phosphatase concentration by a factor of 3.5, a partial dephosphorylation of the complete AT8 epitope on wild type phospho-Tau could be obtained, with 30% of the intensity at the position of T205 after 16 hours of incubation at 25uC.