Spinal nerve injury-induced macrophage infiltration in DRGs is reduced in TLR2 knock-out mice. (A and C) L5 DRGs of sham-operated WT (WT Sham), TLR2 knock-out (TLR2 Sham), and nerve-injured WT and TLR2 knock-out mice (n = 3) at 7 dpi were stained with anti-Iba-1 and anti-CD68 antibodies. Iba-1 or CD68 immunoreactivities (green) were merged with NeuN-IR (red) neurons in DRG. Low magnification images (75x) of DRG tissue are shown as subsets in each panel. The expression levels of Iba-1 and CD68 were quantified by measuring the fluorescence intensity (B and D). Scale bars: 50 μm. Data are presented as mean ± SEM. (*, p < 0.05; ##, **, p < 0.01; ##, sham vs. 7 dpi mice; *, **, WT vs. TLR2 knock-out mice).