Effect of oligonucleotides to β mRNA on β-globin mRNA levels. Ba/F3-EpoR cells were cultured in IL-3 (lane 1) or with 20 mmol/L antisense (lane 2), sense (lane 3), or nonsense (lane 4) in the presence of Epo, and β-globin message levels were determined by northern blot analysis. The increased levels of β-globin mRNA induced by Epo were identical in each of the samples containing oligodeoxynucleotides.