Fig. 1.

Differential effects of TLR4 on clinical score and allodynia with K/BxN serum transfer. Male (A-D) and female (E–H) WT mice and Tlr4^−/− mice (were injected on days 0 and 2 with K/BxN sera and developed transiently increased clinical scores with paw inflammation (A, E) and allodynia (C, G). The AUCs of aggregate arthritis scores were calculated for all groups. All strains and sexes increased AUCs of arthritis scores compared to their respective naïve controls (B and F, *p = 0.0001 and one-way ANOVA with Tukey post hoc test). Associated allodynia resolved in the Tlr4^−/− male mice but not in the WT male mice (C). The AUCs of aggregate hyperalgesic indices were calculated for all groups. Increased hyperalgesic indices were observed in male and female WT K/BxN mice compared to WT naïve (D and H, respectively, *p = 0.001 and ^*p = 0.0001, one-way ANOVA with Tukey post hoc test) and hyperalgesic indices for Tlr4^−/− K/BxN mice compared to WT K/BxN mice, ^#p = 0.007 and p = 0.002). Data are represented as mean ± SEM with n = 6 per group