FIG. 4.

Coculture of BM or WJ MSCs with CB CD34⁺ cells supports the expansion of CB CD34⁺ cells in the presence of TPO. CB CD34⁺ cells obtained from different donors (n = 5) were cultured with TPO for 10 days in the presence or absence of MSCs obtained from different sources. Next, the composition of the expanded cells was analyzed using flow cytometry and the capacity to form myeloid colonies was analyzed with CFU assays. (A) Fold expansion (depicted as the total number of hematopoietic nucleated cells after culture divided by the number of input cells) in the absence or presence of stromal cells. (B) Percentage of the three major populations of the total hematopoietic cells observed after expansion in the absence or presence of stromal support from MSCs from different sources; rCD34⁺ = residual CD34 cells, Lin⁻ = CD34⁻CD61⁻Lineage⁻ cells, and CD61⁺ = CD34⁻CD61⁺ cells. (C) Colony-forming capacity of TPO-expanded CD34⁺ cells after culture in the absence or presence of stromal support (*P < 0.05).