Evaluation of human cord blood CD34+ hematopoietic stem cell differentiation to megakaryocyte on aminated PES nanofiber scaffold compare to 2-D culture system.

Context: Recently, umbilical cord blood (UCB) has been recognized as a suitable potential source of hematopoietic stem/progenitor cells (HSPCs) for transplantation. Lengthy thrombocytopenia after UCB transplantation is a major problem because of insufficient megakaryocyte (Mk) progenitors, which results in delayed platelet recovery. Frequent allogenic platelet transfusion leads to resistance to platelet units and higher risk of transmission of pathogenic agent.

Objective: Ex vivo expansion of HSPCs and their differentiation to Mk progenitors on aminated PES nanofiber could lead to faster platelet recovery after UCB transplantation.

Materials And Methods: CD34 cells were positively enriched using the MidiMACS system. CD34(+) cells were seeded onto conventional culture and aminated PES scaffold. The proliferation of CD34(+) cells, and also their differentiation into Mk progenitors, were evaluated. We used the flow cytometric method for analyzing CD41 and CD61 markers and real-time PCR for the expression level of transcription factors, as NF-E2 and GATA-1.

Results: This study indicated increased CD34(+) cell population in aminated PES compared to the conventional system. After differentiation, the amount of CD41/CD61-expressing cells and the quantity of NF-E2 expression level increased in the aminated PES versus the 2-D system. The quantity of GATA-1 expression level was reduced on CD41/CD61(+) cells compared to CD34(+) cells, with no difference between the aminated PES and the conventional system.

Discussion: Aminated PES nanofiber could have more effect on the proliferation of CD34(+) cells and Mk differentiation than the conventional culture.

Conclusion: Injection of the expanded cells and differentiated Mk progenitors, along with the transplantation of UCB stem cells might accelerate recovery of platelets and decrease the period of thrombocytopenia after transplantation.