Fig. 3: Age estimation of mouse and human immune cells using epigenetic clocks.

a, Left: linear regression plots of mouse T cell age and average methylation levels of ML EA-associated genes. Right: linear regression plots of mouse T cell age and Horvath panmammal epigenettic clock. Pearson correlation coefficient (cor) is shown in each plot. The error band represents the mean ± 1.96 × standard error of the mean. b, Left: linear regression plots of SJLIFE healthy control (HC) chronologic age versus average PBMC methylation level. Right: linear regression plots of SJLIFE HC chronologic ages and Horvath epigenetic age estimation based on the PBMC methylation profile. Pearson cor is shown in each plot. The error band represents the mean ± 1.96 × standard error of the mean. c, Summary graph of average ML EA-associated methylation levels for human naive, Tcm, Tem and CMV-specific (Tetramer+) memory T cell samples. n = 3–5 for the biologically independent samples. Senescence resistant (Senes. Res.) program means the 139 top DMRs between endogenous and 4LT memory T cells. d, Horvath epigenetic clock age estimation of CMV-specific (n = 5) and naive (n = 4) CD8⁺ T cells. The P value is based on a two-sided Student’s t-test. The error bars represent the standard deviation. e, Representative DNA methylation plots of CDKN2A/2B gene cluster among naive CD8⁺ T cells, CMV-specific CD8⁺ T cells and T-ALL. f, Summary graph for p15 promoter methylation among naive CD8⁺ T cells, CMV-specific CD8⁺ T cells and T-ALL. n = 4–7 for the biologically independent samples. The P values are based on a two-sided Student’s t-test. For all box plots, the box and hinges correspond to the first, second and third quartiles, the upper whisker extends to the minimum (largest value, upper hinge + 1.5 × interquartile range) and the lower whisker extends to the maximum (smallest value, lower hinge − 1.5 × interquartile range).