Dataset Information

Imaging of carrageenan-induced local inflammation and adjuvant-induced systemic arthritis with [(11)C]PBR28 PET.

ABSTRACT: [(11)C] PBR28 binding to translocator protein (TSPO) was evaluated for imaging of acute and chronic inflammation using two established rat models.Acute inflammation was induced by local carrageenan injection into the paw of Fisher 344 rats (model A). T-cell mediated adjuvant arthritis was induced by heat-inactivated Mycobacterium butyricum injection in Lewis rats (model B). Micro-PET scan was performed after injection of approximately 35 MBq [(11)C]PBR28. In model A, volumes of interest (VOIs) were defined in the paw of Fisher 344 rats (n=6) with contralateral sham treatment as control. For model B, VOIs were defined in the tail, sacroiliac joints, hips, knees and thigh muscles of M. butyricum treated animals (n=8) and compared with sham-treated controls (n=4). The peak (11)C-PBR28 SUV (SUVpeak) and area under the curve (AUCSUV) of 60-minute time-activity data were calculated. Immunohistochemistry for CD68, a macrophage stain, was performed from paw tissues. In addition, the [(11)C]PBR28 cell uptake was measured in lipopolysaccharide (LPS)-stimulated and non-stimulated macrophage cultures.LPS-stimulated macrophages displayed dose-dependent increased [(11)C]PBR28 uptake, which was blocked by non-labeled PBR28. In both models, radiotracer uptake of treated lesions increased rapidly within minutes and displayed overall accumulative kinetics. The SUVpeak and AUCSUV of carrageenan-treated paws was significantly increased compared to controls. Also, the [(11)C]PBR28 uptake ratio of carrageenan-treated vs. sham-treated paw correlated significantly with CD68 staining ratios of the same animals. In adjuvant arthritis, significantly increased [(11)C]PBR28 SUVpeak and AUCSUV values were identified at the tail, knees, and sacroiliac joints, while no significant differences were identified in the lumbar spine and hips.Based on our initial data, [(11)C]PBR28 PET appears to have potential for imaging of various inflammatory processes involving macrophage activation.

SUBMITTER: Shao X

PROVIDER: S-EPMC3788650 | biostudies-literature | 2013 Oct

REPOSITORIES: biostudies-literature

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Imaging of carrageenan-induced local inflammation and adjuvant-induced systemic arthritis with [(11)C]PBR28 PET.

Shao Xia X Wang Xueding X English Sean J SJ Desmond Timothy T Sherman Phillip S PS Quesada Carole A CA Piert Morand R MR

Nuclear medicine and biology 20130725 7

<h4>Introduction</h4>[(11)C] PBR28 binding to translocator protein (TSPO) was evaluated for imaging of acute and chronic inflammation using two established rat models.<h4>Methods</h4>Acute inflammation was induced by local carrageenan injection into the paw of Fisher 344 rats (model A). T-cell mediated adjuvant arthritis was induced by heat-inactivated Mycobacterium butyricum injection in Lewis rats (model B). Micro-PET scan was performed after injection of approximately 35 MBq [(11)C]PBR28. In ...[more]

PMID: 23891203

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Dataset Information

Imaging of carrageenan-induced local inflammation and adjuvant-induced systemic arthritis with [(11)C]PBR28 PET.

Publications

Imaging of carrageenan-induced local inflammation and adjuvant-induced systemic arthritis with [(11)C]PBR28 PET.

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