APOE and atherosclerosis: One piece of evidence for their mechanistic role in atherosclerosis was provided by an experiment involving the depletion of CD8+ T cells in Apoe−/− mice using anti-CD8α antibodies, which resulted in a significant reduction in plasma CCL2 levels, as well as the accumulation of macrophages and a reduction in atherosclerotic plaque size in the early stages of disease progression.