Figure 6

Injection of needle-shaped HA particles modulates cell recruitment in vivo. Female C57BL/6 mice (n = 3) aged 6–8 weeks were injected intraperitoneally with PBS vehicle, N₅ (1 mg/mouse) or S₂₀ 1–6 µm (1 mg/mouse) HA particles. Twenty-four hours, three days and seven days later peritoneal lavage cells were collected. (A) PECS were stained to analyse cell recruitment by flow cytometry. Cells were characterized using a combination of markers for peritoneal resident macrophages (CD11b^hi F4/80^hiMHCII⁻), mast cells (SiglecF⁻ cKit⁺) monocytes (CD11b⁺ SiglecF⁻ F4/80⁻ Gr1int SSC^low), neutrophils (CD11b⁺ SiglecF⁻ F4/80⁻ Gr1^hi) and eosinophils (CD11b⁺ SiglecF⁺ Gr1⁻ SSC^hi). Data are expressed as number of single/live cells. (*p < 0.05, **p < 0.01, ***p < 0.001). (B) PECs were restimulated with complete RPMI 1640 medium or heat-killed Escherichia coli (10 bacteria/cell) for 24 h. Supernatants were assessed for IL-10 and TNF-α secretion by ELISA. Results are mean cytokine concentrations (±SEM) for triplicate samples (vs PBS **p < 0.01, ***p < 0.001).