Fig. 3

CD4 and CD8 T-cells recovered from human brain and trigeminal ganglia express an effector memory phenotype. Mononuclear cells were isolated from paired peripheral blood (blood), normal appearing white matter (NAWM) and trigeminal ganglia (TG) of deceased brain donors (n = 8). Frequencies of CD45RA⁺, CD27⁺, CCR7⁺, CD28⁺, KLRG1⁺, CD127⁺ and PD1⁺ CD8 (a) and CD4 (b) T-cells were quantified using flow cytometry. Each dot represents data obtained from one individual; see Table 1 for reference symbols used for each brain donors, and bars show mean value. P values were calculated using Friedman test with Dunn’s multiple comparisons test between blood, NAWM and TG (not discriminating between HSV1⁻ and HSV1⁺ TG). Mann–Whitney test was performed to compare TG-derived CD8 and CD4 T-cells recovered from HSV-1 naïve (HSV-1⁻) with latently HSV-1-infected individuals (HSV-1⁺). * p < 0.05 and ** p < 0.001