Fig. 1.

Multiple cell origin of TSPO in the pathological human brain. Astrocytes and perivascular macrophages are positive for TSPO in acute hemorrhagic leukoencephalopathy (A, B). At the site of injury, acute stroke cells express TSPO in two separate cases (C, D). A schizophrenia patient with TSPO+ microglia and endothelial cells in the anterior cingulate cortex (E). Lesions in progressive multifocal leukoencephalopathy are abundant with TSPO in microglia, macrophages, and astrocytes in the white and gray matter (F, G, H). Patients with frontotemporal dementia with mutations for TDP, proganulin, and FUS have a macrophage-like cells expressing TSPO in the white matter and in perivascular spaces (I, J, K, L). Macrophages in vanishing white matter express TSPO throughout the white matter areas in the brain parenchyma (M, N). Fragile X-associated tremor/ataxia syndrome has TSPO+ astrocytes in the white matter and microglia in both white and gray matter (O, P)