FIGURE 3.

HMGB1 increases macrophage chemotaxis in vitro and in vivo in a TLR4-dependent manner. A, the number of macrophages (MΘ) found to migrate toward formylmethionylleucylphenylalanine by Transwell assay ± HMGB1 (100 ng/ml) *, p < 0.05, three separate experiments. Ctrl, control. B and C, confocal micrographs showing F-actin in RAW264.7 macrophages ± HMGB1 (100 ng/ml). Arrows denote filopod-like extensions, bar = 10 μm, D, flow cytometric analysis of peritoneal lavage effluent obtained from C3H/HeOUJ and C3H/HeJ mice that had been injected with either PBS or HMGB1 3 h earlier. FITC, fluorescein isothiocyanate. E and F, quantification of the percentage (E) and number (F) of macrophages migrating into the peritoneal fluid as indicated, *, p < 0.05 versus by analysis of variance. Error bars indicate S.E.