The goal of this study is to investigate whether the fusion protein PEP-1-MsrA can efficiently enter cells to protect against oxidative stress and to attenuate atherosclerosis in apolipoprotein E deficient (apoE−/−) mice, providing evidence that PEP-1-MsrA may be a potential therapeutic agent for atherosclerosis-related cardiovascular diseases. The gene discussed is APOE; the disease is atherosclerosis.