Figure 3

MPO positive cells and neutrophils proximal to and at acute rupture sites. A. 3 mm proximal to an acute rupture site there were only scattered MPO-positive macrophages at the luminal surface. B. The rupture site demonstrates numerous MPO positive cells. C and D are corresponding images of the sites of A and B, respectively, demonstrating that many of the MPO positive cells express cathepsin G, a neutrophil marker.