Fig. 7: Evaluation of 20D9h3-DUBA toxicity towards healthy short and long-term progenitors in vitro.

A CD34-positive BM cells from healthy human donors (5 × 10⁴ cells per condition) were treated with 1 µg/ml 20D9h3-DUBA, 20D9h3-MMAF or IgG1-DUBA for 96 h. On day 4, all remaining cells were plated in methylcellulose without further treatment and total colony counts were evaluated after 14 d. Counts were normalized to untreated control. mean±s.d.; n = 5 donors (except 20D9h3-MMAF group: n = 4 donors). ns, not significant by Kruskal-Wallis test; each p value is adjusted to account for multiple comparisons. B CD34-positive BM cells from healthy human donors were treated with 0.2 and 1 µg/ml 20D9h3-DUBA or 20D9h3-MMAF or 1 µg/ml IgG1-DUBA or IgG1-MMAF for 48 h. Remaining cells were harvested and cultured on a layer of irradiated M2-10B4 murine fibroblasts for 5 weeks without further treatment. After 5 weeks, all cells were harvested and plated in methylcellulose. Total colony numbers were assessed after 14 d and normalized to untreated control. mean±s.d.; n = 3 donors, each including two technical replicates. *P < .05 by One-way ANOVA; each p value is adjusted to account for multiple comparisons.