Identification and absolute numbers of 4 subpopulations—T_N, T_SCM, T_CM, and T_EM—divided from the CD4⁺ T cells of HTLV-1 carriers and ATL patients. (A) Top panels show a scheme to isolate the T_N, T_SCM, T_CM, and T_EM populations from PBMCs. After excluding dendritic cells, monocytes, and natural killer cells, we gated CD4⁺ cells and then separated into 4 subpopulations. The lower panels show representative data from a HI, a HTLV-1 carrier, and ATL patients. Additional data from other samples are presented in supplemental Figure 1. (B-C) Absolute numbers of each population (T_N, T_SCM, T_CM, and T_EM) or the CD45RO⁺ memory T-cell population (T_CM + T_EM) in peripheral blood from HIs (n = 5), HTLV-1 carriers (n = 3), and ATL patients (n = 17) were calculated with PBMC counts and fluorescence-activated cell sorting (FACS) analysis. Each value is presented in supplemental Table 4. P values by Dunn’s multiple comparisons test after Kruskal-Wallis test are presented. Bars indicate means.