Monday April 23 2007
CEA
A novel radiotracer for imaging neuroinflammation
Journal of Nuclear Medicine (2007) 48(4) : 573-581.
CEA
Challenges: to detect the precursor signs of neurodegenerative diseases such as Alzheimer’s disease as early as possible
Any organ can host an inflammatory reaction as a response designed to guarantee the body’s integrity. The brain demonstrates inflammatory processes following cerebrovascular accident, or during neurodegenerative disorders such as Alzheimer’s disease. A core feature of these processes is the activation microglial cells, the immune cells resident in the brain. Although the effects of microglia on neurons have yet to be fully elucidated, microglial activation appears to be closely linked to neuronal disorder, to the point that it serves as an indirect marker. Non-invasively detecting microglial activation via positron emission tomography (PET) using a specific cellular radiotracer is viable option for detecting the onset of neurodegenerative disease at the earliest stage possible and, more importantly, evaluating the effectiveness of novel neuroprotective drugs. The only radiotracer made available to date, [11C]PK11195, cannot be deployed in this kind of protocol because its non-specific baseline binding level is too low to quantify neuroinflammation.
A team from the Frédéric Joliot Hospital Service (SHFJ) recently used a PET camera designed for pre-clinical neuroimaging to demonstrate that [11C]DPA-713, a new radiotracer developed in partnership with an Australian research team from Sydney University, was able to yield contrasted images and more reliably quantify neuroinflammatory processes than the reference tracer. Although other molecules are being studies in other research centres, [11C]DPA-713 looks to be a strong candidate as an efficient substitute to [11C]PK11195 for the study and in vivo tracking of neuroinflammation.
The swell of interest into reliable biomarkers of neurodegenerative disease that are useable in humans has triggered a race between research laboratories to discover new PET tracers of neuroinflammation. A race that is crucial to driving therapeutic innovation forward.
Reference: Hervé Boutin, Fabien Chauveau, Cyrille Thominiaux, Marie-Claude Grégoire, Michelle James, Régine Trebossen, Philippe Hantraye, Frédéric Dollé, Bertrand Tavitian, et Michael Kassiou (2007). [11C]DPA-713: a novel peripheral benzodiazepine receptor PET ligand for in vivo imaging of neuroinflammation. Journal of Nuclear Medicine. 48(4) : 573-81.