PET imaging in multiple sclerosis: Focus on the translocator protein

Abstract

PET imaging offers the potential of high specifi city for molecular markers of neuroinfl ammatory processes in Multiple Sclerosis. The most extensively characterized target is the 18 KDa translocator protein (TSPO). Autoradiography studies suggested that TSPO density mainly refl ects activated microglia in Multiple Sclerosis patients’ brain. PET studies showed an increased TSPO signal in the white and gray matter of MS patients, that correlated with disease severity. New generation TSPO PET tracers with improved imaging characteristics are promising, but require further characterization to clarify their full potential for application in Multiple Sclerosis. With the development and validation of a wider range of molecular targets, the impact of PET imaging on the progress of neurobiological research in Multiple Sclerosis could become potentially crucial.