Northern analysis for human A1 mRNA expression.
WT U937 cells or U937 cells transfected with pLSXN retroviral vector or pLXSN containing Bcl-2 in the sense orientation were exposed to 1 μg/mL bleomycin, which induces myeloid differentiation in these cells (increased granularity and CD11b expression), and assayed for the expression of A1 mRNA. Approximately 20 μg total RNA was loaded in each lane. IL-1–treated A549 lung carcinoma cell line was included (lane 1) for positive control. Other experimental groups included WT U937 cells that were either untreated or treated with bleomycin for 2 and 5 days (lanes 2, 3, and 4, respectively); U937 cells expressing Bcl-2 that were either untreated or treated with bleomycin for 2 and 5 days (lanes 5, 6, and 7, respectively); and vector-transfected U937 cells that were either untreated or treated with bleomycin for 2 and 5 days (lanes 8, 9, and 10, respectively). Northern blot was hybridized to a randomly primed32P-labeled A1 cDNA. Autoradiograph was developed after 6 days exposure to x-ray film using 2 intensifying screens at − 80°. Photograph of the corresponding ethidium bromide–stained gel is shown below the autoradiograph for loading control.
