Atherosclerotic lesions. Typical appearance of aortas from apoE^+/+HCII^−/− (A) and apoE^−/−HCII^−/− (B) mice. Mice were fed a Western diet beginning at 8 weeks of age and were killed at 20 weeks of age. To show the entire aorta in a single image, each panel is a composite of 3 adjacent microscopic fields. Atherosclerotic plaques are present in the aortic arch and to a lesser extent in the thoracic aorta of the apoE^−/−HCII^−/− mouse (B).