[18F]FDG PET/CT is a quantitative tool to probe vascular inflammation and immune system metabolic activation in atherosclerotic nonhuman primates

Figures

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  Fig. 1. Study design and PET/CT image analysis. The study included 27 crab-eating macaques, divided into two groups based on their diet: an atherogenic diet group (n = 15) and a chow diet group (controls; n = 12). Whole-body 2-deoxy-2-[fluorine-18]fluoro-D-glucose ([18F]FDG) positron emission tomography–computed tomography (PET/CT) imaging was conducted on all animals. Image analysis quantified [18F]FDG uptake in vasculature (abdominal aorta [ABD], infrarenal aorta [IR], suprarenal aorta [SR], partial aortic section near the renal arteries [P2_R]), lymphoid organs (spleen and bone marrow [BM]), and fat tissues (subcutaneous adipose tissue [SAT], visceral adipose tissue [VAT]), as well as vascular calcification (VC) in the ascending aorta and arch

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  Fig. 2. 2-deoxy-2-[fluorine-18]fluoro-D-glucose ([18F]FDG) positron emission tomography–computed tomography (PET/CT) imaging of crab-eating macaques in the atherogenic diet group and chow diet group (controls). (a) Representative [18F]FDG PET/CT images demonstrating increased [18F]FDG uptake in vascular (abdominal aorta [ABD]) and bone marrow (BM) tissues of the atherogenic diet group. The scale bar indicates standardized uptake value (SUV). (b) Representative CT images demonstrating increased vascular calcification (yellow arrows) in the aorta of atherogenic diet group. The scale bar indicates Hounsfield units (HU). LV, left ventricle. (c) Quantification of [18F]FDG uptake in various regions of interest: abdominal aorta (ABD), suprarenal aorta (SR), infrarenal aorta (IR), partial aortic section near renal arteries (P2_R), bone marrow (BM), spleen, subcutaneous adipose tissue (SAT), and visceral adipose tissue (VAT). (d) Quantification of vascular calcification (VC). Each point represents an individual animal with the median (solid lines) and quartiles (dotted lines). p-values were determined using Mann–Whitney test with multiple comparison corrections. Asterisks indicate statistical…

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  Fig. 3. Correlation of vascular positron emission tomography–computed tomography (PET/CT) measurements with metabolic activity of lymphoid organs, and adipose tissues in crab-eating macaques. (a) Correlation matrix illustrating Spearman correlation coefficients (rs) among 2-deoxy-2-[fluorine-18]fluoro-D-glucose ([18F]FDG) uptake (measured by target-to-background ratio, TBRmean) in selected regions of interest (abdominal aorta [ABD], suprarenal aorta [SR], infrarenal aorta [IR], partial aortic section near renal arteries, [P2_R], bone marrow [BM], spleen, subcutaneous adipose tissue [SAT], visceral adipose tissue [VAT], and vascular calcification [VC] measured by HUmax). Strong, |0.7|≤ rs ≤|1|; Moderate, |0.3|≤ rs <|0.7|; Weak, 0 ≤ rs <|0.3|. (b–e) Pairwise correlation between vascular inflammation (ABD, SR, IR, and P2_R) and vascular calcification (VC, b), bone marrow metabolic activity (BM, c), and adipose tissue metabolic activity (visceral adipose tissue [VAT, d] and subcutaneous adipose tissue [SAT, e], respectively). Each point represents an individual animal. Solid lines indicate the linear regression fits, and dashed lines represent 95% confidence intervals. Asterisks indicate…