Figure 1. Regression of plaques in the mouse transplantation model.
ApoE−/− mice were fed a Western diet for 16 weeks to develop advanced atherosclerosis. Aortic arches from these mice were either harvested and analyzed by histochemical methods, or they were transplanted into apoE−/− (‘progression’) or wild-type (‘regression’) recipient mice. Three or seven days later, the same analyses were performed. Shown are the histochemical results for the foam-cell marker CD68 (red). The pictures show the immunostaining of representative aortic lesions in cross section. The virtual absence of foam cells can be seen in the ‘regression’ group. In contrast with the ‘regression’ results, the ‘progression’ group showed persistence of foam cells. (Adapted from Trogan E, Feig JE et al. PNAS 2006;103:3781–3786).