CD4 and myocardial infarction: We are under the impression that T cells and macrophages are the primary cells infiltrating atherosclerotic plaques and ultimately causing ACS such as MI.[36] Most plaque T cells are CD4 + TCRαβ+ T cells, which play a key pathogenic role in atherosclerosis,[37] but as early as the 1970s, Gershon and Kondo discovered that T cells not only enhance the immune response but also suppress it.[38] which was later named regulatory T cells (Tregs).