Figure 4.
Granulocyte-differentiated HL-60 cells migrate across T84 inverted monolayers. (a) DMSO-differentiated HL-60 cells migrate across T84 monolayers similar to neutrophils. DMSO dHL-60 cells were allowed to migrate across inverted T84 monolayers for 2 hr in response to 10−8 m C5a or 10−7 m fMLP. Black bars: migration to chemoattractant alone, open bars: migration to the chemoattractant in the presence of 30 µg/ml of intact anti-β2 antibody. Each bar is the mean percentage migration of three independent experiments ± SEM. (b) β2 integrin independent migration of dbcAMP-differentiated HL-60 cells in response to C5a. DbcAMP dHL-60 cells were stimulated, with the indicated concentrations of C5a, to migrate across inverted T84 monolayers for 2 hr. Bars are the mean percentage migration ± SEM from five experiments using dbcAMP-differentiated HL-60 cells and 10−8 m C5a as a chemoattractant across T84 monolayers (P = 0·1482). (c) Migration across T84 monolayers does not induce significant Mac-1 up-regulation on dbcAMP-differentiated HL-60 cells. HL-60 cells were differentiated for 2 days, washed and allowed to migrate in response to C5a for 2 hr across inverted T84 monolayers. Transmigrated cells were collected and stained for CD11b expression. Similar results were obtained in three experiments.