(A) Northern blot analyses of mRNA for eosinophil granule proteins in normal human bone marrow (hBM) cells cultured with IL-5. hBM cells were cultured in the presence or absence of the supernatant (10% vol/vol) from X63Ag8-653-mIL-5 myeloma cells as a source of IL-5. Total RNA was obtained at days 0, 3, 6, 9, and 12 of culture. Each lane contains 8 μg of total RNA. Exposure to x-ray film was for 18 hours. (B) mRNA expression for hGATA-1 in normal hBM cells cultured with IL-5. Southern blot analysis of RT-PCR products amplified from 1 μg of total RNA extracted from hBM cells cultured in the presence or absence of the supernatant from X63Ag8-653-mIL-5 myeloma cells as a source of IL-5. Total RNA was obtained at days 0 (lane 1), 3 (lanes 2 and 6), 6 (lanes 3 and 7), 9 (lanes 4 and 8), and 12 (lanes 5 and 9) of culture. The blot was probed simultaneously with hGATA-1 cDNA and β-actin as an internal control. Each lane contains 1/10th of the amplification products from each time point. (C) Northern blot analysis of mRNA for hGATA-2 in hBM cells stimulated with (IL-5) or without (FCS alone) the supernatant from X63Ag8-653-mIL-5 myeloma cells as a source of IL-5. Total RNA was obtained at days 0, 3, 6, and 9 of culture. Each lane contains 3.5 μg of total RNA.