APOE and atherosclerosis: As shown in Fig. 2, along with the increased level of atherosclerosis-related effector cells, Treg and IMC unexpectedly accumulated in the spleen of Apo E−/− mice that appeared to closely relate to the progression of atherosclerosis (Treg: from 6.58±0.77 to 30.00±5.53; IMC: from 2.38±0.33 to 5.42±0.45).