Eur J Neurol 2003 May;10(3):257-264
Debruyne JC, Versijpt J, Van Laere KJ, De Vos F, Keppens J, Strijckmans K, Achten E, Slegers G, Dierckx RA, Korf J, De Reuck JL.
Department of Neurology, Ghent University Hospital, Ghent, Belgium; Division of Nuclear Medicine, Ghent University Hospital; Laboratory of Radiopharmacy, Ghent University; Laboratory of Analytical Chemistry, Institute for Nuclear Sciences, Ghent University; Department of Radiology, MR-Unit, Ghent University Hospital, and Department of Biological Psychiatry, University Hospital, Groningen, The Netherlands; Both authors contributed equally to this manuscript.
Activated microglia are involved in the immune response of multiple sclerosis (MS).
The peripheral benzodiazepine receptor (PBR) is expressed on microglia and up-regulated after neuronal injury.
[11C]PK11195 is a positron emission tomography (PET) radioligand for the PBR.
The objective of the present study was to investigate [11C]PK11195 imaging in MS patients and its additional value over magnetic resonance imaging (MRI) concerning the immuno-pathophysiological process.
Seven healthy and 22 MS subjects were included.
Semiquantitative [11C]PK11195 uptake values were assessed with normalization on cortical grey matter.
Uptake in Gadolinium-lesions was significantly increased compared with normal white matter.
Uptake in T2-lesions was generally decreased, suggesting a PBR down-regulation.
However, uptake values increased whenever a clinical or MR-relapse was present, suggestive for a dynamic process with a transient PBR up-regulation.
During disease progression, an increase of normal-appearing white matter (NAWM) uptake was found, propagating NAWM as the possible real burden of disease.
In conclusion, [11C]PK11195 and PET are able to demonstrate inflammatory processes with microglial involvement in MS.