Abstract: Objective To study the effects of interferonγ(IFN-γ) on in vitro terminal erythroid differentiation. Methods Real-time PCR was used to detect the expression of IFN-γ receptors during erythroid differentiation of K562 induced by hemin. Both hemin-induced K562 cells and human umbilical cord CD34+ cell derived primary erythroid cells were treated with IFN-γ. Erythroid differentiation of the cells was evaluated using real-time PCR to detect the mRNA level of erythroid specific surface markers CD71 and CD235a, and benzidine staining assay was applied to explore the change of hemoglobin expression. Results The expression of IFN-γ receptors in K562 cells was first decreased and climbed up again after reaching the lowest point at 48 h of hemin induction. IFN-γ treatment increased CD71 and CD235a expression in both hemin-induced K562 cells and the later stage (E15D) primary erythroid cells. Benzidine staining showing increased globin protein expression in hemin-induced K562 cells after IFN-γstimulation. Furthermore, our results indicate that IFN-γ promotes hemin-induced K562 erythroid differentiation in a time dependent manner. Mechanistically, the results showed that IFN-γ treatment stimulates the expression of erythroid transcription factors NFE2, which is critically for erythroid maturation. Conclusions IFN-γ accelerates terminal erythroid differentiation in hemin-induced K562 cells and human umbilical cord CD34+ derived primary erythroid cells.

Key words: IFN-γ, erythroid differentiation