Quantitative Assessment of Macrophage Activity in Inflammatory Bowel Disease using Fluorine-19 MRI & the Response to Treatment

Deepak K. Kadayakkara^1,2, Eric T. Ahrens^1,2

In this study, we characterize inflammatory burden in a mouse model of inflammatory bowel disease (IBD) by in situ macrophage labeling using perfluorocarbon emulsion. Using fluorine-19 MRI, changes in bowel inflammation and macrophage activity in response to treatments are monitored non-invasively in vivo. In vivo MRI results are validated by ex vivo MRI of the excised colon samples, confocal microscopy, histology score and qRT PCR analysis of macrophages. Our results demonstrate that fluorine-19 MRI is an effective method to quantitatively measure macrophage activity in vivo and assess treatment response in IBD.