Neuroinflammation is a well-orchestrated, dynamic, multicellular process playing a major role in neurodegenerative disorders.
The microglia which make up the innate immune system of the central nervous system are key cellular mediators of neuroinflammatory
processes. In normal condition they exert a protective function, providing tissue repair by releasing anti-inflammatory cytokines and neurotrophic
factors. Upon neuronal injury or infection, they become overactivated, thereby releasing neurotoxic substances, amplifying neuroinflammation
leading to neurodegeneration. Positron emission tomography (PET) provides a sensitive non-invasive imaging technique
to study and quantify receptor and enzyme expression. A radiolabeled tracer for a protein (over)expressed in neuroinflammation and
more specifically for the overactivated microglia would be useful as a diagnostic tool in the follow-up of neuroinflammation progression
and to study the efficacy of anti-inflammatory therapy over time. In this manuscript, an overview of potential PET tracer targets upregulated
during neuroinflammation is provided together with the current radiotracers used to image these targets. In addition, lead structures
to develop radiotracers for new targets are suggested.