Temporal and noninvasive monitoring of inflammatory-cell infiltration to myocardial infarction sites using micrometer-sized iron oxide particles

Yidong Yang, Yuhui Yang, Nathan Yanasak, Autumn Schumacher, Tom C C Hu

Research output: Contribution to journalArticle

40 Scopus citations


Micrometer-sized iron oxide particles (MPIO) are a more sensitive MRI contrast agent for tracking cell migration compared to ultrasmall iron oxide particles. This study investigated the temporal relationship between inflammation and tissue remodeling due to myocardial infarction (MI) using MPIO-enhanced MRI. C57Bl/6 mice received an intravenous MPIO injection for cell labeling, followed by a surgically induced MI seven days later (n = 7). For controls, two groups underwent either sham-operated surgery without inducing an MI post-MPIO injection (n = 7) or MI surgery without MPIO injection (n = 6). The MRIs performed post-MI showed significant signal attenuation around the MI site for the mice that received an intravenous MPIO injection for cell labeling, followed by a surgically induced MI seven days later, compared to the two control groups (P < 0.01). The findings suggested that the prelabeled inflammatory cells mobilized and infiltrated into the MI site. Furthermore, the linear regression of contrast-tonoise ratio at the MI site and left ventricular ejection function suggested a positive correlation between the labeled inflammatory cell infiltration and cardiac function attenuation during post-MI remodeling (r2 = 0.98). In conclusion, this study demonstrated an MRI technique for noninvasively and temporally monitoring inflammatory cell migration into the myocardium while potentially providing additional insight concerning the pathologic progression of a myocardial infarction.

Original languageEnglish (US)
Pages (from-to)33-40
Number of pages8
JournalMagnetic Resonance in Medicine
Issue number1
StatePublished - Jan 2010
Externally publishedYes



  • Cardiac MRI
  • Cardiac remodeling
  • Imaging
  • Inflammation
  • MPIO contrast agent
  • Myocardial infarction
  • Prelabeling

ASJC Scopus subject areas

  • Radiology Nuclear Medicine and imaging

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