Molecular Imaging of Atherosclerotic Plaques Targeted to Oxidized LDL Receptor LOX-1 by SPECT/CT and Magnetic Resonance

Abstract

Background-The oxidized low-density lipoprotein receptor (LDLR) LOX-1 plays a crucial role in atherosclerosis. We sought to detect and assess atherosclerotic plaque in vivo by using single-photon emission computed tomography/ computed tomography and magnetic resonance imaging and a molecular probe targeted at LOX-1. Methods and Results-Apolipoprotein E Ϫ/Ϫ mice fed a Western diet and LDLR Ϫ/Ϫ and LDLR

Development of111In-Labeled Liposomes for Vulnerable Atherosclerotic Plaque Imaging

“…Liposomes can act as a platform for various other imaging modalities, such as MR imaging and optical imaging. Recently, several liposome-based atherosclerosis imaging probes for various imaging modalities have been reported (33)(34)(35). Because liposomes are biocompatible and have long histories as drug carriers for human use (36), such imaging probes, including the liposome system we have described, should be good candidates for clinical use in the future.…”

Capping it off

“…Since inflammation is present throughout the life of the lesion, from inception to rupture, and is only extinguished as lesions calcify, 14 it may not be a suitable marker to identify patients at imminent risk for vascular events. The same can be said for lipoprotein cholesterol, 15 oxidized lipoprotein cholesterol, 16,17 or identification of cellular elements such as macrophages and T-cells (see Figure 1). As a result, imaging lipids, inflammation, or cells may be very useful to define the presence and location of lesions, but not as a marker of vulnerability.…”

“…density lipoprotein-cholesterol. 25 These cells become stressed, causing them to release MMPs and undergo apoptosis. Both apoptosis and the release of MMPs appear to identify a later stage in the evolution of the lesion than pan atheroma markers, such as inflammation or lipoprotein-cholesterol or oxidized lipoprotein cholesterol.…”

A review of molecular imaging of atherosclerosis and the potential application of dendrimer in imaging of plaque

“…oxLDL binding to LOX-1 will induce apoptosis as well as expression of adhesion molecules and MMP and activate the inflammatory pathway, all of which eventually contribute to the rupture of the plaques. [45][46][47][48] In view of high expression of LOX on more than one kind of cells concerned in AS, LOX-1 will have great potential to be a target for molecular imaging of AS plaques. At present, imaging probes targeted at LOX-1 have been developed to improve sensitivity, specificity, and biocompatibility compared to the nontargeted ones.…”

“…50 Li et al 47 prepared an imaging probe consisting of liposomes loaded with LOX-1 antibody or nonspecific immunoglobulin G and tested their imaging effects using SPECT/CT and magnetic resonance. The LOX-1 targeted probes could bind to atherosclerotic plaques, especially to the shoulder areas of the plaque, a region with features of vulnerable plaque and LOX-1 expresses extensively, while nontargeted ones could not.…”