Figure 2.

Cells that have undergone their first division exhibit transcriptional heterogeneity. (a) t-distributed Stochastic Neighborhood Embedding (tSNE) of 6000 expressed genes from single CD8⁺ T cells from the following populations: naïve (gray), Division 1 (red), Day 4 (orange), Day 7 (yellow), central memory (T_CM) (green) and effector memory (T_EM) cells. Each circle represents a single cell. Inset, separation of Division 1 cells by tSNE clustering analysis into two distinct subpopulations, labeled Div1_TE (red) and Div1_MEM (blue) cells. TE, terminal effector; MEM, memory. (b) Differential expression of genes among Div1_TE (top) and Div1_MEM (bottom) cells presented as a heatmap. (c–e) Expression of selected genes previously associated with CD8⁺ T cell differentiation among individual naïve (gray), Div1_TE (red), and Div1_MEM (blue) cells, presented as violin plots, ordered alphabetically. Higher expression in Div1_TE relative to Div 1_MEM cells (c), lower expression in Div1_TE relative to Div1_MEM cells (d), or equal expression in Div1_TE and Div1_MEM cells (e).