Evaluation of the PBR ligand [123I]CLINDE in an animal model of experimental autoimmune encephalomyelitis

Objectives: The aim of this study was to evaluate the Peripheral Benzodiazepine Receptor (PBR) radioligand [123I]CLINDE in the rat inflammatory disease model of Experimental Autoimmune Encephalomyelitis (EAE). Methods: EAE was induced with blast cells collected from spleen and lymph nodes of Lewis rats induced with myelin basic protein and complete Freund's adjuvant. Biodistribution with [123I]CLINDE was undertaken on EAE rats exhibiting different disease severity and compared to controls.The relationship between inflammatory lesions and tracer uptake was investigated using ex vivo autoradiography and immunohistochemistry. Results: Disease severity was confirmed by histopathology in spinal cord. Results indicate enhanced uptake of [123I]CLINDE in all animals induced with EAE compared to controls. This uptake reflected the ascending nature of the inflammatory lesions ie. uptake in the lumbar spinal cord > thoracic cord > cervical cord > medulla > cerebellum. Uptake of [123I]CLINDE in the lumbar and thoracic cord correlated with disease severity. A 2 and 3 fold enhancement in PBR expression was observed in the brain and spinal cord of animals with a clinical score of 3 compared to controls. Regional [123I]CLINDE uptake closely correlated with localisation of PBR, shown using autoradiography and immunohistochemisty. Conclusions: These results demonstrate the ability of [123I]CLINDE to measure in vivo changes of PBR density according to area of involvement and the severity of disease suggesting it as a potential SPECT tracer for the study of inflammation and multiple sclerosis. © 2022 Journal of Nuclear Medicine

Keywords

Ligands, Rats, Animal cells, Proteins, Lymph nodes, Freunds adjuvant, Diseases, Immune system diseases

Citation

Mattner, F., Linares, D., Staykova, M., Gregoire, M.-C., Pham, T., Bourdier, T., Quinlivan, M., Callaghan, P., Willenborg, D., & Katsifis, A. (2008). Evaluation of the PBR ligand [123I]CLINDE in an animal model of experimental autoimmune encephalomyelitis. Paper presented to the Society of Nuclear Medicine (SNM) 2008 Annual Meeting, New Orleans, Louisiana, USA, June 14 - 18, 2008. In Journal of Nuclear Medicine, 49, (Supplement 1), 81P. Retireved from: http://jnm.snmjournals.org/content/49/supplement_1/81P.1.abstract