Fig. 7

Analysis of CD8 T cell differentiation. (a) Intracellular expression of Granzyme B, TNF-α, and IL-2 in CD8 T cells (CD3+ CD4- T cells) after PMA/Ionomycin stimulation for 3 h. (b) Percentage of expression of CD57, KLRG1, PD1, TIGIT, CD127/ILR-7 on CD8 T cells. (c) Within CD8 T cells, short-lived effector cells (SLEC) and memory precursor effector cells (MPEC) were identified as KLRG1+ CD127-, and KLRG- CD127+, respectively. (d) Percentage of SLEC and MPEC CD8 T cells. Results were shown in PBMC from young (circles) and elderly (triangles) donors, control (white symbols) and TBI patients (black symbols). (e) Percentage of SLEC, and (f) of MPEC CD8 T cells, was also shown separating patients according to injury severity assessed by GCS score. In elderly TBI patients, the injury severity (GCS score, panel g) and the 6-month outcome (GOSE value, panel h) were correlated (Spearman correlation) with the percentage of MPEC cells. * p < 0.05; ** p < 0.01; *** p < 0.001 TBI vs. control aged-matched subjects. §§ p < 0.01; §§§ p < 0.001 young vs. elderly control subjects. # p < 0.05; ## p < 0.01; ### p < 0.001 young vs. elderly TBI patients