APOE and atherosclerosis: Co-localization of cathepsins (B, L, S and K) and macrophages in the core of atherosclerotic lesions of apoE−/− mice and human patients has been documented many times [20–24, 28, 29, 31, 34, 35], confirming an important role of these proteases in the progression of atherosclerosis associated inflammation and the development of vulnerable plaques.