Fig. 8

CXCR5-mediated NF-κB phosphorylation contributes to mechanical allodynia of CPIP mice via upregulating pro-inflammatory cytokine in SCDH. A Western blot showing expression of pNF-κB and NF-κB in ipsilateral SCDH of WT + sham, WT + CPIP and Cxcr5^−/− + CPIP groups. Upper panel indicate representative blot images and lower panel indicates pooled data. B Experimental protocol illustrating time points for behavioral test and intrathecal injection of NF-κB inhibitor PDTC (300 μg/5 μL)/vehicle (20% DMSO + 80% PBS) or IL-6 neutralizing antibody (10 ng/10 μl)/isotype control IgG (in PBS). C 50% PWT changes in ipsilateral hindpaw after intrathecal PDTC or vehicle in CPIP and sham group mice. D Double immunostaining of pNF-κB with Nissl, GFAP or Iba-1 in ipsilateral SCDH of CPIP mice. The dashed box area is further enlarged and shown on the right panel. White arrows denote co-localization. DAPI staining is shown in purple. Scale bar indicates 50 μm. E–G Gene expressions of Il6, Ccl2 and Ccl3 in ipsilateral SCDH of 3 groups by qPCR. H 50% PWT of ipsilateral hindpaws of CPIP mice treated with IL-6 neutralizing antibody or corresponding vehicle. *p < 0.05, **p < 0.01. n = 5–9 mice/group. Two-way ANOVA with repeated measures followed by Tukey’s post hoc test was used for comparisons in C, H. One-way ANOVA followed by Tukey’s post hoc test was used for comparisons in others