CD4⁺ T cells breach SGC barrier surrounding neurons in DRG tissue from naïve and PTX-treated mice.

(A-E) Immunohistochemical (IHC) staining of neurons (PGP9.5: cyan), SGCs (GLAST: magenta), and T cells (CD3: green, CD4: red) in lumbar 4 (L4) DRG tissue from naïve and day 14 PTX-treated female and male mice. (A) Representative widefield fluorescence of CD4⁺ T cells (CD3⁺ CD4⁺) and neurons (PGP9.5⁺) in close proximity (solid arrow = absence of GLAST; dashed arrow = occluded by GLAST) in DRG tissue from naïve and PTX-treated female mice. (B) Quantification of the number of CD4⁺ T cells per mm² of DRG tissue in female and male naïve and PTX-treated mice (day 7 and 14) (n = 8). (C) Differential inference contrast (DIC), fluorescence, and merged confocal Z-slice images of a CD4⁺ T cell between the SGC barrier and a PGP9.5⁺ DRG neuron from a PTX-treated female mouse. (D) 3D projection of a CD4⁺ T cell shown in (C, S1 Fig in S1 File and S1 Video). (E) Maximum projection images of a CD4⁺ T cell that breached the SGC barrier surrounding a neuron in DRG tissue from a naïve female mouse.