Figure 6.
Time- and dose-dependent induction of IL-8 secretion by HP-NAP. (A,B) Time- and dose-dependent secretion of IL-8 from ATRA-induced differentiated HL-60 cells induced by HP-NAP. ATRA-induced differentiated HL-60 cells at a density of 1 × 106 cells/mL were stimulated with 1 μM HP-NAP or D-PBS, pH 7.2, as the unstimulated control at 37 °C for the indicated time (A) or stimulated with the indicated concentrations of HP-NAP (B) at 37 °C for 16 h. The amount of IL-8 release was measured from the culture supernatants by ELISA. Data are expressed as mean ± SD of four and three independent experiments for A and B, respectively. (C) Time-dependent secretion of IL-8 from neutrophils induced by HP-NAP. Neutrophils at a density of 2.5 × 106 cells/mL were treated with 1 μM HP-NAP and D-PBS, pH 7.2, as the unstimulated control at 37 °C for the indicated time. The amount of IL-8 release was determined as described in (A,B). Data are expressed as mean ± SD of four independent experiments. *: p < 0.05, **: p value < 0.01, ***: p < 0.001 as compared with the unstimulated cells.