TREM2 and Parkinson disease: TREM2 inhibits inflammatory responses in microglia via suppression of NF‐kB pathways and activation of innate immunity,29 while TREM2 loss of function results in reduced microglial phagocytosis.30, 31, 32 Therefore, measuring TREM2 levels in the CSF may provide another important pharmacodynamic effect indicating neuroinflammation and the phagocytic activity of microglia to potentially reduce alpha‐synuclein levels after treatment of PD patients with Nilotinib.