OBJECTIVE(S): Erythropoiesis is regulated by some extrinsic and intrinsic 
factors as microRNAs (miRNAs). miRNAs are endogenously small non-coding 
regulatory RNAs which play vital roles in the variety of cellular fate, critical 
processes; growth, apoptosis, metabolism, survival of the cells and specially 
differentiation. Several miRNAs such as miR-16 and miR-451 have been shown to be 
correlated with erythroid differentiation. Taking into account the importance of 
miRNAs in cellular differentiation, the goal of the present study was to examine 
the role of miRNAs in hematopoietic stem cells (HSC) differentiation into the 
erythroid cells in the absence of growth factors and stimulatory cytokines.
MATERIALS AND METHODS: CD133+ stem cells were infected with lentiviruses 
containing miR-451/miR-16 precursor sequence, erythroid differentiation was 
evaluated using RT-PCR for hemoglobin chains and surface antigens, also by 
banzidine staining.
RESULTS: MiR-451up-regulation, but not miR-16, could induce α, β and γ-globin 
expression in CD133+ cells and have strong correlation with appearance of CD71 
and CD235a markers in these cells. Moreover, miR-451 up-regulation increases the 
banzidine positive cells to ~ %40.
CONCLUSION: Our results provide strong evidence that miR-451 up-regulation 
strongly induces erythroid differentiation and maturation of CD133+ stem cells. 
Hence, this method may provide a useful technique for the production of 
artificial blood RBC and be used as a new strategy for gene therapy of 
hemoglobinopathies, such as β-thalassemias and sickle cell anemia.