Eotaxin induces the proliferation of FDCP-1 but not FDCP-MIX IL-3–dependent myeloid cell lines. FDCP-1 (A) or FDCP-MIX cells (B) (5,000 cells/well) were seeded in 96-well plates and supplemented with the different growth factors. Thymidine incorporation was measured after 24 hours as counts per minute (CPM)/well. FDCP-1 (5 × 10³) cells were seeded in 24-well plates and stimulated with different concentrations of Eotaxin. Cells were collected and counted after 6 days (C). Five different experiments were performed. The results shown are of one representative experiment. Each point is the mean of three determinations ± SD.