Scientific Journal of

  Abstract

 Background and Objectives

 Bone marrow transplantation with umbilical cord blood (UCB) in adult recipients is limited mainly by a low CD34⁺ cell dose. To overcome this shortcoming by minimum manipulation, mineralized bone allograft (MBA) scaffold coated by UCB-USSC (unrestricted somatic stem cells) was used to expand CD34⁺ cells from UCB.

 Materials and Methods

 In this experimental study, UCB-USSCs were isolated and characterized by morphologic and immunophenotypical analysis. Then they were seeded on MBA (for 3D figuration) and culture plate (for 2D figuration) as a feeder layer. CD34⁺ cells were isolated from the UCB (by MACS method) and were expanded in 2D and 3D conditions for 3 weeks. At the end, cell count, flow cytometry, cologenic assay, and LTC-IC were done.

 Results

 After 3 weeks, ex vivo expansion of UCB-CD34⁺ was enhanced 250 ± 13.2 in 3D. The highest CFC expansion and LTC-IC were observed at day 14. Flow cytometry analysis showed the lowest percentage in 3D culture.

 Conclusions

 USSCs by 3D MBA structure produce the hematopoietic cytokine, extracellular matrix and binding molecules they also create the intercellular interaction that can be used as a suitable feeder layer. It provides an ex vivo mimicry of bone marrow niche by enhancing surface/volume ratio. This model could be a suitable and alternative environment for HSCs expansion and hematopoiesis.