MAPT and tauopathy: Our recent in vitro binding assays using human brain homogenates have indicated that [11C]PBB3 does not cross‐react with monoamine oxidases A and B,35 which is in clear distinction from properties of other tau radioligands, including [18F]AV‐145136 and [18F]THK5351.37 This observation, however, does not fully ensure the selectivity of [11C]PBB3 for tau fibrils in PET imaging of living patients with tauopathies.