Carole Escartin, PhD, Centre National de la Recherche Scientifique, Université Paris Saclay, Fontenay-aux-roses, France, discusses the promise of astrocyte-based biomarkers in central nervous system (CNS) disease, injury, or infection. Reactive astrogliosis occurs in response to pathology, when astrocytes undergo morphological, molecular, and physiological remodeling, and take on new functions in response to their environment. While the contexts in which astrocyte reactivity can occur are numerous and highly variable, astrocyte-based markers are still a promising avenue to aid in diagnosis and to demonstrate target engagement of future astrocyte-directed therapies in clinical trials. Radiotracers can be used to visualize astrocyte reactivity. For example, TSPO-PET enables neuroinflammation imaging and may be useful as a tool to evaluate novel therapeutic effects. Several other radiotracers that are more specific to astrocytes are in development, such as BU99008 which targets imidazoline-2 binding sites on astrocytes and shows regional binding in Alzheimer’s disease brains. Glial fibrillary acidic protein (GFAP) is also a widely used marker of astrocyte reactivity that can be detected in body fluids. GFAP upregulation appears to occur as an early response to neurological trauma across many types of CNS disorders. Continued discovery and validation of astrocyte-based biomarkers is a research priority to support CNS drug development. This interview took place at the Alzheimer’s Association International Conference (AAIC) 2022 in San Diego, CA.
