Fig. 3: Antigen-specificity correlates with age-related phenotypic changes.

CD8⁺ T cells from peripheral blood of 9 older (O, > 65 years, mean age of 71.9 years) adults were analyzed by spectral flow cytometry as described in Fig. 1 and contrasted to those of 8 young (Y) adults from Fig. 1 and Supplementary Fig. 1. A UMAP reference plot of bulk CD8⁺ T cell subsets based on integrated data from Y and O adults, as well as their distributions shown separately for Y and O. B Frequencies of EBV tetramer-positive cells for different antigens. C Reference mapping results depicting side-to-side comparison of the phenotypic distribution of tetramer-positive cells in 8 Y and 9 O adults. D Bubble plot comparing distributions of tetramer-positive cells among CD8⁺ T cell clusters defined in (A). The bubble size and color reflect the proportion of antigen-specific T cells in a given cluster. E Probability vectors describing the subset distributions of tetramer-positive cells in Y and O adults were compared. Significance levels between the indicated pairwise comparisons are shown as bubble size and color. F Protein levels of indicated molecules in tetramer-positive cells of 8 Y and 9 O adults as assessed by spectral flow cytometry. Data show the median with 95% confidence intervals (B), median (D) or mean ± SEM (F). All datapoints represent distinct biological replicates. Data were compared by two-way ANOVA with Šídák’s multiple comparisons test (B, F) or by two-sided permutation tests (E). Source data are provided as a Source Data file.