title: In Vivo Imaging of Human Neuroinflammation.
abstract: Neuroinflammation is implicated in the pathophysiology of a growing number of human disorders, including multiple sclerosis, chronic pain, traumatic brain injury, and amyotrophic lateral sclerosis. As a result, interest in the development of novel methods to investigate neuroinflammatory processes, for the purpose of diagnosis, development of new therapies, and treatment monitoring, has surged over the past 15 years. Neuroimaging offers a wide array of non- or minimally invasive techniques to characterize neuroinflammatory processes. The intent of this Review is to provide brief descriptions of currently available neuroimaging methods to image neuroinflammation in the human central nervous system (CNS) in vivo. Specifically, because of the relatively widespread accessibility of equipment for nuclear imaging (positron emission tomography [PET]; single photon emission computed tomography [SPECT]) and magnetic resonance imaging (MRI), we will focus on strategies utilizing these technologies. We first provide a working definition of "neuroinflammation" and then discuss available neuroimaging methods to study human neuroinflammatory processes. Specifically, we will focus on neuroimaging methods that target (1) the activation of CNS immunocompetent cells (e.g. imaging of glial activation with TSPO tracer [(11)C]PBR28), (2) compromised BBB (e.g. identification of MS lesions with gadolinium-enhanced MRI), (3) CNS-infiltration of circulating immune cells (e.g. tracking monocyte infiltration into brain parenchyma with iron oxide nanoparticles and MRI), and (4) pathological consequences of neuroinflammation (e.g. imaging apoptosis with [(99m)Tc]Annexin V or iron accumulation with T2* relaxometry). This Review provides an overview of state-of-the-art techniques for imaging human neuroinflammation which have potential to impact patient care in the foreseeable future.
authors.forename: Daniel S
authors.initials: DS
authors.lastname: Albrecht
authors.affiliation: Neuro-Immunology, Neurology Division, Department of Clinical Neurosciences, Centre Hospitalier Universitaire Vaudois and University of Lausanne, CH-1011 Lausanne, Switzerland.|LTS5, Ecole Polytechnique Fédérale de Lausanne, CH-1015 Lausanne, Switzerland.
authors.forename: Cristina
authors.initials: C
authors.lastname: Granziera
authors.forename: Jacob M
authors.initials: JM
authors.lastname: Hooker
authors.forename: Marco L
authors.initials: ML
authors.lastname: Loggia
mesh_terms: D001931:Brain Mapping; D002490:Central Nervous System / Q000000981:diagnostic imaging*; D006801:Humans; D007249:Inflammation / Q000000981:diagnostic imaging / Q000473:pathology*; D059906:Neuroimaging
keywords: MRS; Neuroimmunology; astrocyte; blood-brain barrier; brain imaging; microglia