Effect of MNC therapy on superoxide anion production in the aorta of apoE KO mice. Top panel contains representative cross-sections stained with dihydroethidium (DHE) showing a bright ethidium fluorescence (red) in the apoE KO mouse compared to the apoE KO-MNC mouse (original magnification × 20. Bar: 50 μm). Bar graph shows average DHE fluorescence (AU: arbitrary units) comparing apoE KO to apoE KO-MNC mice. Values are means ± SEM. *p < 0.05 compared to apoE KO, Student's t test).