Inhibition of BFU-E and CFU-E colony formation in erythroid cells cocultivated with HZ or treated with HNE. Primary erythroid cell cultures were cocultivated with HZ (25μM HZ-heme), treated with HNE (7μM), or kept as untreated controls (CTRL). At indicated times cells were taken from the liquid culture and 10³ cells were seeded in semisolid medium to assess their BFU-E, CFU-E, and CFU-GM colony-forming ability. One representative experiment of 5 is shown.