HMGB1 enhances CXCL12-induced migration via CXCR4 and is independent from RAGE or TLR signaling. (A–F) Migration induced by CXCL12 ± 300 nM HMGB1 on murine BM cells from C57BL/6 WT (A), MyD88^−/− (B), Rage^−/− (C), Tlr4^−/− (D), and Rage^−/− in the presence of 10 µg/ml LPS-Rs (E) or murine pre-B 300.19 cells transfected with human CXCR4 (F). Migrated cells were counted in five high-power fields (HPF) and are shown as mean ± SEM of four independent experiments performed with cells from different mice (**, P < 0.01; ***, P < 0.005, ANOVA plus Bonferroni posttest).