Effects of in vitro expansion of CD133+ hematopoietic stem cells isolated from umbilical cord blood in expression of microRNAs involved haematopoiesis

 Introduction: Hematopoiesis is regulated by different microRNAs (miRNA). These small regulatory RNAs control hematopoiesis at different stages with changing in the expression of genes at post-transcriptional levels. Treatment of various diseases is increasing with using CD133+ hematopoietic cells isolated and in vitro expanded from the umbilical cord blood. This study was performed to show alteration of microRNAs levels involved in hematopoiesis in CD133+ hematopoietic cells isolated and invitro expanded from the umbilical cord blood. Materials and Methods: Umbilical cord blood CD133+ hematopoietic stem cells were isolated by MACS and then the cells confirmed and counted by using flowcytometery and finally were divided into two groups .In the first group RNA was extracted from the cells and the cells in the second group were cultured invitro for 12 days and then these cells were used to assess micoRNAs expression using qPCR real time. Results: The results showed that from 23 microRNAs, expression of 11 microRNAs was the same in two groups whereas expression of 7 and 5 microRNAs were respectively increased and decreased following in vitro culture. Conclusion: Based on our results, in vitro expansion of the hematopoietic stem cells results in increased microRNAs levels which are responsible for differentiation and decreased microRNAs levels which are responsible for self- renewal.