Astrocytic TSPO Upregulation Appears Before Microglial TSPO in Alzheimer's Disease.

Background: In vivo PET/SPECT imaging of neuroinflammation is primarily based on the estimation of the 18 kDa-translocator-protein (TSPO). However, TSPO is expressed by different cell types which complicates the interpretation.

Objective: The present study evaluates the cellular origin of TSPO alterations in Alzheimer's disease (AD).

Fluorescence-activated cell sorting to reveal the cell origin of radioligand binding.

Many studies have explored the role of TSPO (18 kDa translocator protein) as a marker of neuroinflammation using single-photon emission computed tomography (SPECT) or positron emission tomography (PET). In vivo imaging does not allow to determine the cells in which TSPO is altered. We propose a methodology based on fluorescence-activated cell sorting to sort different cell types of radioligand-treated tissues.