Fig. 1

Study design. CSF sampled at several time points following oral administration of semagacestat was subjected to labeling using TMT reagents 128-131. The combined labeled samples from each participant (TMT 6-plex set) were centrifuged through a 30 kDa molecular weight cut-off filter. The flow-through, containing the endogenous peptide fraction, was analyzed by LC-MS. The relative change in concentration of each identified peptide was calculated from the TMT reporter ion signals. CSF cerebrospinal fluid, TMT tandem mass tag, LC-MS liquid chromatography-mass spectrometry