To examine the contribution of intrinsic DNAm alterations of leukocyte subtypes to PWB alterations observed during aging, DNAm profiles for CD4+ T cells (Set 8 described in Table 1) and CD14+ monocytes (Set 9 described in Table 1) were collected from the Multi-Ethnic study of Atherosclerosis (MESA, [13]). Here, CD4 is linked to atherosclerosis.