Figure 4.

MRI tracking of bCD-PLL-labeled EPCs migrating to ischemic muscle and Gd concentrations measured via ICP-MS. (A) Representative T₁-weighted spin echo images with color-scaled signal intensities and (B) the T₁ relaxation times in hindlimb muscle observed at different times after the injection of bCD-PLL-labeled EPCs or control saline. The arrows indicate contrast enhancement at the periphery of ischemic muscle on days 3 and 5 after the injection of bCD-PLL-labeled EPCs. (C) Gd concentrations measured in ischemic and nonischemic muscle tissue via ICP-MS. **P<0.01, ***P<0.001.

Abbreviations: EPC, endothelial progenitor cell; MRI, magnetic resonance imaging; bCD, bacterial cytosine deaminase; PLL, poly-L-lysine; ICP-MS, inductively coupled plasma mass spectrometry; IS, ischemic.