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Figure 6 The Effects of PDT on Plaque Cell Composition

Green bars are drug-only controls, whereas brown bars represent drug and light combination. Panel A shows that the area of plaque (mm²) occupied by macrophages is reduced by photodynamic therapy (PDT) at 7 days after treatment and that macrophage removal is sustained at 28 days after PDT regardless of elevated plasma cholesterol, an acute inflammatory stimulus (n = 12 arteries/group). Panel B shows transient loss of plaque smooth muscle cells/mm² of plaque at 7 days after PDT, followed by an increase in -actin area by 28 days, indicative of plaque repopulation with a stable plaque cell phenotype (n = 12 arteries/group). *p < 0.05; ***p < 0.001.