Fig. 6: CXCR2 expressed in nociceptive DRG neurons contributes to CXCL5-induced mechanical allodynia and joint inflammation in mice.

A Schematic picture showing the overall design of Cxcr2 conditional knockout mice in nociceptive DRG neurons using SNS-Cre mouse line. B Immunostaining showing CXCR2 expression in DRG and spleen of Cxcr2^fl/fl and SNS-Cre Cxcr2^fl/fl mice. Scale bars, 50 µm (DRG) and 100 µm (Spleen). C Summary of % of CXCR2 positively expressing (CXCR2⁺) cells in DRG. D Summary of CXCR2 fluorescence intensity/field in the spleen. E Western blot showing CXCR2 expression in DRG (left) and SCDH (right) of Cxcr2^fl/fl and SNS-Cre Cxcr2^fl/fl mice. F, G Comparisons of CXCL5-induced mechanical allodynia and ankle diameter between Cxcr2^fl/fl and SNS-Cre Cxcr2^fl/fl mice. CXCL5 (300 ng/site) was injected into the ankle joint of mice after the baseline test (0 h). H–K qPCR showing inflammation-related gene expressions, including Il1b, Tnfa, Il6, and Ifng. *p < 0.05, **p < 0.01. Two-way ANOVA (repeated measures) with Bonferroni’s post hoc test was used (panels F and G). One-way ANOVA with Bonferroni’s post hoc test for panels (H–K). Student’s unpaired t-test (two-tailed) was for others. Data are shown as mean ± SEM. The n number, exact p-value, and statistical results are provided as a Source Data file. The mouse schematic picture in panel A was drawn using SciDraw (https://scidraw.io/).