Characterization of Megakaryocyte Progenitor Cells Differentiated from Umbilical Cord Blood CD133+ and CD133- Cells

Objective: Thisstudywas performed todeterminetheimmunophenotype of Megakaryocyte progenitor cells differentiated from UCB CD133+ and CD133- cells under the effects of interleukin-3 (IL-3), interleukin-6 (IL-6), stem cell factor (SCF) and thrombopoietin (TPO) in vitro. Materials and Methods: CD133+and CD133- cells were isolated by using CD133 isolation kit following the manufacturer s instructions. Then, they were seeded in liquid serum free expansion mediums supplemented with the cytokine cocktail including IL-3, IL-6, SCF and TPO. The expression rate of CD34, CD41, CD61 and CD42b were measured on the days aand 7 of culture using flow cytometry. Student s t-test was used for the comparisons and a p value less than 0.05 was considered to be significant. Results: Expressions of megakaryocytic markers on CD133+ cells were always higher than CD133- cells. CD133+ cells have higher potential of generating Mk colonies in vitro. Conclusion: CD133+subset may be used as an alternative source for Mk progenitor cells production and these cells may improve platelet recovery after UCB transplantation.