Figure 3: Presence of MPO-Containing Inflammatory Cells in Infarcts During Late Remodeling Phase

(A) Immunostaining on days 7 and 14 post-MI reveals higher CD11b and MPO staining areas as compared with no MI (n = 3 to 5/group). Low-magnification midventricular sections of day 7 and 14 infarcts show extensive left ventricular thinning and remodeling (scale bar: 2 mm). Inset: high-magnification histology (scale bar: 100 μm) shown at days 7 and 14. (B) Percentage of MPO- and CD11b-positive areas per high power field (HPF). (C) Dot plots showing increased CD11b positive cells/leukocytes (blue boxes) in hearts of 7- and 15-day-old infarcts as compared with hearts without infarcts. Neutrophils (red boxes) and Ly-6Chigh monocytes (green boxes) were also significantly elevated at both time points. Data plotted as mean ± SEM. *p < 0.05; **p < 0.01. Abbreviations as in Figures 1 and 2.