Longitudinal changes of T-cell subsets in PB and CLL-affected organs in aging Eµ-TCL1 and WT mice and after AT. At least 2 cohorts of 3-, 6, and 12-month (mo)-old Eµ-TCL1, WT, and AT mice containing ≥5 mice each were euthanized and PB, and single-cell suspensions of CLL-affected organs were stained for CD3, 4, 8, 62L, 44, and CCR7 (spleen only) and assessed in relation to CLL load (supplemental Figure 1). Dead cells were excluded by 4,6 diamidino-2-phenylindole. Groups were compared with 3-month-old mice. Mann-Whitney test was used for nonnormally distributed data and unpaired t test for normally distributed data, as determined by Shapiro-Wilk normality test. (A) Longitudinal changes of percentages of CD3⁺, CD3⁺CD4⁺, and CD3⁺CD8⁺ cells in spleens, leading to (B) changes in CD4⁺/CD8⁺ ratios in spleen, which were recapitulated in (C) PB, LNs, and BM. (D) Longitudinal changes of percentages of spleen CD44^-CD62L⁺ naive, CD44⁺CD62L⁺ memory, CD44⁺CD62L⁻ effector, and (E) CD62L⁺CCR7⁺ central memory (CM) and CD62L⁻CCR7⁻ EM CD3⁺CD8⁺ cells. Longitudinal changes of percentages of naive, memory, and effector CD3⁺CD8⁺ cells in (F) PB, (G) LNs, and (H) BM (EM and CM cells were not assessed in these compartments/organs). All graphs depict median ± interquartile range and combine data from at all cohorts of mice at each age group. (I) Heat map summary of P values describing statistical differences in T-cell subsets in spleen identifying CLL-specific T-cell subset phenotype vs aging-related patterns. Groups were compared with 3-month-old mice. Blue, expansion; red, loss of cell subsets; ns = nonsignificant. *P < .05, **P < .001, ***P < .0001.