UM171 increases engraftment of CD34⁺ cells in xenografts. (A) Outline of assay. CD34⁺ cells from patients with SCD were prestimulated and transduced with LV-GFP in the presence or absence of UM171 and transduced cells were injected into NBSGW mice. (B) Engraftment of CD34-derived CD45⁺ cells and (C) gene-marked CD45⁺ cells in BM of NBSGW mice at week 16 after transplant. (D) Lineage distribution and (E) the percentage of gene-marked human cells from BM. Data represent mean ± SD, n = 6, each data point represents an individual mouse. ∗P < .05; ∗∗P < .01.