Antisense phosphorothioate DNA oligonucleotides to REDK promote erythroid colony formation.

(A) Low-density mononuclear bone marrow cells were plated in semisolid medium with EPO after incubation with sense (S223) or antisense (AS155, AS244, AS480) phosphorothioate DNA oligonucleotides. CFU-E were scored at 7 days in multiple wells. (B) Antisense oligonucleotides inhibit in vitro transcription/translation. TnT reactions containing the REDK-L cDNA were incubated with no oligo or with 5 or 10 μmol/L S223, AS155, or AS244. Products were determined by Western blot analysis. (C) Antisense phosphorothioate DNA oligonucleotides to REDK stimulate early erythroid progenitors. Low-density mononuclear bone marrow cells were plated in semisolid medium with saturating, synergistic factors (methycellulose-based medium) after incubation with sense (S223) or antisense (AS155, AS244, AS480) phosphorothioate DNA oligonucleotides. BFU-E was scored at 12 days in multiple wells.