Despite the umbilical cord blood(ucb) benefits – easy access , availability , rich sources of hematopoietic stem cells(hscs) , low number of hscs in one unite of ucb has been a limitation for adult cd133+ transplantation. the expansion of cd133+ in culture is one approach to overcome this problem. in this study, we evaluated the expansion of ucb-hscs on plla scaffold as well as inhibiting the tgf- _ signaling pathway through reduction of tgf- _rii expression
Materials and methods: cd133+cells were isolated from ucb by macs technique and transfected by sirna targeting tgf- _riimrna. cd133+cells were expanded on plla scaffold in presence serum free medium containing growth factors. thise culture condition was evaluated for the number of total nucleated cells (tncs), cd133+ surface marker as well as using cfu assay on day 7 after culture.
Results: the fold increase in cd133+ cells, tncs, and colony numbers was observed to be highest in plla scaffold(3d)culture medium compared to 2d.the difference between number of cells in 3d compared to 2d was statistically significant (p < 0.05)
The results showed that transfection of cd133+cells with sirna targeting tgf- _rii and using 3d culture system considerably increase the number of progenitors. therefore, this method could be useful for ucb-hscs expansion.