Figure 4

Osteoblast-EVs enhance ex vivo expansion of CD34⁺ cells.

(a,b) Osteoblast-EVs increase the expansion of (a) total nucleated cells (TNCs) and (b) CD34⁺ cells after 10 days of expansion with SCF and Flt3L compared to cells cultured in the absence of EVs (control) (N = 7). Expansion is shown as fold change (FC) increase in total cell number compared to input. **P < 0.01, compared with control by Student’s t-test. (c) Osteoblast-EVs increase the number (mean ± SD) of phenotypic HSCs (lin⁻ CD34⁺ CD38^low CD45RA^low CD90⁺) compared to control on day 10 (N = 3). ***P < 0.005, compared with control by Student’s t-test. (d) EV-expanded immature UCB cells retain their differentiation capacity in colony forming unit (CFU) assay (mean ± SD) (N = 3). The frequencies of the myeloid and erythroid lineages are shown in the table.