Figure 4. Damage to the neuronal and glial networks is caused by CD4⁺ and CD8⁺ T cells.

(A and F) GI transit was measured after oral gavage of carmine red dye. (A) Transit time for sham- or WNV-infected WT or TCRbd^–/– mice at 7 dpi. (B–D, G, and H) The muscularis externa was isolated from (B–D) middle and distal regions of the small intestine of sham- or WNV-infected WT or TCRbd^–/– mice at 7 dpi, (G and H) middle regions of the small intestine of sham- or WNV-infected WT mice at 7 dpi that were treated with anti-CD4 and/or anti-CD8β or isotype control mAbs and stained for (B and G) calretinin⁺ and nNOS⁺ neurons, (C) WNV antigen, (D) S100β⁺ glia, or (H) and S100β⁺ glia and WNV antigen. The fraction of the area that stained positive for calretinin, nNOS, or S100β was determined, and the values were normalized to values for (B and D) WT sham-infected mice or (G and H) animals treated with an isotype control mAb. Representative images from the myenteric plexus of the middle region of the small intestine. Scale bars: 100 μm. Original magnification, ×2.5 (enlarged insets). (C) Data are presented as the percentage of WNV antigen⁺ area in the field of view. (E) Counts of live CD45⁺TCRβ⁺CD4⁺ or CD8⁺ T cells in the muscularis of sham- or WNV-infected C57BL6/J mice at 7 dpi. (F) Transit time for sham- or WNV-infected mice at 7 dpi; mice were treated with anti-CD4 (α-CD4) and/or anti-CD8β or isotype control mAbs. Data were pooled from (A) 3; (C–E, and G) 2; and (F) 4 experiments. The numbers of mice per group were as follows: (A) n = 7–13; (C and D) n = 5–8; (E) n = 6–7; (F) n = 8–18; (G) n = 7–8; (H) n = 6–8. Lines in A, E, and F and column heights in B–D, G, and H indicate mean values. *P < 0.05, **P < 0.01, and ***P < 0.001, by (A, B, D, G, and H) Kruskal-Wallis ANOVA with Dunn’s post test (all groups compared with each other); (F) Kruskal-Wallis ANOVA with Dunn’s post test (compared with the isotype control group); and (C) 2-tailed Mann-Whitney U test.