Patterns of USPIO Deposition in Murine Atherosclerosis

Abstract

In Response: We thank Klug and colleagues for their interest in our recent publication “p38 MAPK Inhibition Reduces Aortic Ultrasmall Superparamagnetic Iron Oxide Uptake in a Mouse Model of Atherosclerosis: MRI Assessment” by Morris et al.1 Indeed the article does underscore the need for further investigation into understanding the fate of ferumoxtran-10 and its modulation of uptake in atherosclerotic plaque of the apoE−/− mouse. Additionally, investigators should be keenly aware of the complexities associated with interpreting the pattern of USPIO deposition which will be affected by numerous variables including animal model of atherosclerosis, atherosclerotic plaque location, USPIO particle size and coating, USPIO dosing paradigm, etc. While we appreciate the continued effort in developing ferumoxtran-10 as a novel cellular readout of macrophage content or inflammation status of the plaque, one must be aware of the complexities in comparing results from experiments using similar animal models but different iron oxide MRI contrast agents. For example in Briley-Saebo et al …