Uptake of inflammatory cell marker [11C]PK11195 into mouse atherosclerotic plaques

Abstract

Our results indicate that the uptake of [(11)C]PK11195 is higher in inflamed atherosclerotic plaques containing a large number of inflammatory cells than in the non-inflamed plaques. However, the tracer uptake to other structures of the artery wall was also prominent and may limit the use of [(11)C]PK11195 in clinical imaging of atherosclerotic plaques.

Evaluation of α v β 3 Integrin-Targeted Positron Emission Tomography Tracer 18 F-Galacto-RGD for Imaging of Vascular Inflammation in Atherosclerotic Mice

“…21 Briefly, 20-m sections of atherosclerotic mouse aorta were warmed to room temperature (RT), preincubated for 5 minutes at RT in PBS buffer, and incubated with 10 nM 18 F-galacto-RGD (specific activity range, 40 to 100 TBq/mmol) in PBS buffer on a spot for 30 minutes at RT. Serial sections were incubated in the presence of 10 mmol of competing unlabeled cyclic RGD pentapeptide (Cilenqitide, Merck KGaA, Darmstadt, Germany).…”

“…The uptake of 18 F-galacto-RGD and 3 H-DG to the vessel wall was studied by digital autoradiography of aortic tissue sections as previously described 20,21 2 ) with an image analysis program (Tina 2.1, Raytest Isotopenmessgeräte, GmbH, Straubenhardt, Germany). After careful coregistration of autoradiography and hematoxylin and eosin-stained histological images, 3 types of regions of interest (ROI) were defined according to morphology in 3 to 7 sections from each mouse: (1) normal vessel wall (no lesion formation, nϭ74), (2) plaque (excluding media, nϭ150), and (3) adventitia (nϭ99).…”

Uptake of 11C-Choline in Mouse Atherosclerotic Plaques

“…The distribution of 11 C-choline to the aortic tissue was studied with digital autoradiography as described before (12). Briefly, after 1 h of exposure the imaging plates were scanned (Imaging Plate BAS-TR2025 [Fuji]; Analyzer BAS-5000 [Fuji]), and the images of aortic sections were analyzed for count densities (photostimulating luminescence units [PSL]/mm 2 ) with an image-analysis program (Tina 2.1; Raytest Isotopenmessgeräte GmbH).…”

Imaging of vulnerable plaque: Potential breakthrough or pipe dream?

“…A PET tracer 11 C-PK11195 binds to peripheral benzodiazepine receptors found especially in macrophages. In a study with this tracer in mice and also in humans, it was found that although the tracer binds to plaques, signifi cant background binding was seen [23,24].…”