Figure 1. Mice immunized with P. gingivalis (A) and C. pneumoniae (B) demonstrated marked atherosclerotic lesions in the proximal aorta, as observed with Oil red O staining, compared with control mice (C) after 26 wks of immunizations. Dark-staining areas in the wall of the aorta are lipid-filled atherosclerotic lesions. Cross-sections of the proximal aorta show atherosclerotic lesions dominated by Mac-3 staining cells (D). Endothelial cells and some lesional cells stain positively for HSP60 (E). Original magnification 40X. Scale shown represents 100 µm.