S-EPMC2923725 - Atherosclerotic plaque composition: analysis with multicolor CT and targeted gold nanoparticles. - OmicsDI

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Dataset Information

Atherosclerotic plaque composition: analysis with multicolor CT and targeted gold nanoparticles.

ABSTRACT:

Purpose

To investigate the potential of spectral computed tomography (CT) (popularly referred to as multicolor CT), used in combination with a gold high-density lipoprotein nanoparticle contrast agent (Au-HDL), for characterization of macrophage burden, calcification, and stenosis of atherosclerotic plaques.

Materials and methods

The local animal care committee approved all animal experiments. A preclinical spectral CT system in which incident x-rays are divided into six different energy bins was used for multicolor imaging. Au-HDL, an iodine-based contrast agent, and calcium phosphate were imaged in a variety of phantoms. Apolipoprotein E knockout (apo E-KO) mice were used as the model for atherosclerosis. Gold nanoparticles targeted to atherosclerosis (Au-HDL) were intravenously injected at a dose of 500 mg per kilogram of body weight. Iodine-based contrast material was injected 24 hours later, after which the mice were imaged. Wild-type mice were used as controls. Macrophage targeting by Au-HDL was further evaluated by using transmission electron microscopy and confocal microscopy of aorta sections.

Results

Multicolor CT enabled differentiation of Au-HDL, iodine-based contrast material, and calcium phosphate in the phantoms. Accumulations of Au-HDL were detected in the aortas of the apo E-KO mice, while the iodine-based contrast agent and the calcium-rich tissue could also be detected and thus facilitated visualization of the vasculature and bones (skeleton), respectively, during a single scanning examination. Microscopy revealed Au-HDL to be primarily localized in the macrophages on the aorta sections; hence, the multicolor CT images provided information about the macrophage burden.

Conclusion

Spectral CT used with carefully chosen contrast agents may yield valuable information about atherosclerotic plaque composition.

SUBMITTER: Cormode DP

PROVIDER: S-EPMC2923725 | biostudies-literature | 2010 Sep

REPOSITORIES: biostudies-literature

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Publications

Atherosclerotic plaque composition: analysis with multicolor CT and targeted gold nanoparticles.

Cormode David P DP Roessl Ewald E Thran Axel A Skajaa Torjus T Gordon Ronald E RE Schlomka Jens-Peter JP Fuster Valentin V Fisher Edward A EA Mulder Willem J M WJ Proksa Roland R Fayad Zahi A ZA

Radiology 20100728 3

<h4>Purpose</h4>To investigate the potential of spectral computed tomography (CT) (popularly referred to as multicolor CT), used in combination with a gold high-density lipoprotein nanoparticle contrast agent (Au-HDL), for characterization of macrophage burden, calcification, and stenosis of atherosclerotic plaques.<h4>Materials and methods</h4>The local animal care committee approved all animal experiments. A preclinical spectral CT system in which incident x-rays are divided into six different ...[more]

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