title: Assessment of cell infiltration in myocardial infarction: a dose-dependent study using micrometer-sized iron oxide particles.
abstract: Myocardial infarction (MI) is a leading cause of death and disabilities. Inflammatory cells play a vital role in the process of postinfarction remodeling and repair. Inflammatory cell infiltration into the infarct site can be monitored using T 2-weighted MRI following an intravenous administration of iron oxide particles. In this study, various doses of micrometer-sized iron oxide particles (1.1-14.5 μg Fe/g body weight) were injected into the mouse blood stream before a surgical induction of MI. Cardiac MRIs were performed at 3, 7, 14, and 21 days postinfarction to monitor the signal attenuation at the infarct site. A dose-dependent phenomenon of signal attenuation was observed at the infarct site, with a higher dose leading to a darker signal. The study suggests an optimal temporal window for monitoring iron oxide particles-labeled inflammatory cell infiltration to the infarct site using MRI. The dose-dependent signal attenuation also indicates an optimal iron oxide dose of approximately 9.1-14.5 μg Fe/g body weight. A lower dose cannot differentiate the signal attenuation, whereas a higher dose would cause significant artifacts. This iron oxide-enhanced MRI technique can potentially be used to monitor cell migration and infiltration at the pathological site or to confirm any cellular response following some specific treatment strategies.
authors.affiliation: Small Animal Imaging, Department of Radiology, Georgia Health Sciences University, Augusta, Georgia, USA.
authors.forename: Yidong
authors.initials: Y
authors.lastname: Yang
authors.forename: Jimei
authors.initials: J
authors.lastname: Liu
authors.forename: Yuhui
authors.initials: Y
authors.lastname: Yang
authors.forename: Sang Hyun
authors.initials: SH
authors.lastname: Cho
authors.forename: Tom C-C
authors.initials: TC
authors.lastname: Hu
mesh_terms: D000818:Animals; D003287:Contrast Media / Q000008:administration & dosage; D004305:Dose-Response Relationship, Drug; D005290:Ferric Compounds / Q000008:administration & dosage; D007249:Inflammation / Q000473:pathology; D007275:Injections, Intravenous; D008279:Magnetic Resonance Imaging / Q000379:methods*; D008297:Male; D051379:Mice; D008810:Mice, Inbred C57BL; D009203:Myocardial Infarction / Q000473:pathology*; D009206:Myocardium / Q000473:pathology
chemical_list: D003287:Contrast Media; D005290:Ferric Compounds; C000499:ferric oxide