SA specifically inhibits fully reduced HMGB1’s chemoattractant activity. (A–C) Dose-dependent inhibition of HMGB1’s chemoattractant activity by SA (A), ac3AESA (B) and amorfrutin B1 (amo B1) (C). Migration of mouse 3T3 fibroblasts in the presence of 1 nmol/L fully reduced HMGB1, but not of 0.1 nmol/L fMLP, was blocked by indicated concentrations of SA, ac3AESA and amo B1. (D) Arg24 and Lys28 are required for binding SA and its derivatives and for their inhibition of HMGB1’s chemoattractant activity by SA, ac3AESA and amo B1. The data represent the mean ± SD (n = 3). Means that are statistically different (Tukey HSD test, P < 0.05) are indicated by different letters over the bar. Means that are not statistically different are indicated by the same letter.