Fig. 4: Asymptomatic HSV-1 brain infection and EAE, individually or combined, induce DNA damage-related foci in spinal cord neurons.

Spinal cord tissue was harvested 14 days after EAE induction, 45–50 days after HSV-1 infection, or mock-treatment alone for detecting the phosphorylation of histone H2AX (γH2AX) by immunohistochemistry. a Representative images showing DNA damage-related γH2AX foci in neurons (black arrows) and non-neuron cells (blue arrows). GM: gray matter; WM: white matter. b Quantification of γH2AX foci in the nucleus of non-neuron cells in the white matter (analysis separated in right and left columns, upper and lower panels, respectively). c Quantification of γH2AX foci in the nucleus of non-neuron cells in the gray matter (analysis separated in ventral and dorsal horns, upper and lower panels, respectively). d Quantification of γH2AX foci in the nucleus of neuron cells in the gray matter (analysis separated in ventral and dorsal horns upper and lower panels, respectively). White bars with circles represent data from healthy mice, orange bars with triangles represent data from mice with HSV-1 infection, blue bars with diamonds represent data from mice with EAE and purple bars with squares represent data from mice with EAE and HSV-1 infection. Values represent means ± SEM of the percentage of γH2AX-positive cells of four mice per group. Data were analyzed using One-way ANOVA followed by Bonferroni’s post-hoc test for multiple comparisons with healthy control mice (n = 2); ****p < 0.001, **p < 0.01, *p < 0.05.