Figure 6.
LUSV eradicates ALL cells via ADCP. (A) Representative images of an in vitro ADCP assay with primary human macrophages (labeled in green) on T-ALL PDX cells (labeled in red) after isotype control or LUSV treatment. (B) Level of in vitro human primary macrophage-mediated phagocytosis induced by increasing concentrations of LUSV on BCP- and T-ALL cell lines as indicated. Correlation between the level of in vitro THP1–mediated phagocytosis induced by LUSV treatment and (C) the level of CD127 expression on leukemic cells or with (D) in vivo efficacy of LUSV treatment (difference in PBBs between respective control and LUSV-treated mice, ΔPBB). Correlation P value and r were measured through the Pearson method. (E-G) Normalized in vivo leukemic burden after control, LUSV-LALAPG, or LUSV treatments in mice injected with either the T-ALL cell line DND41 (IL-7R GoF mutated) (E), the BCP-ALL cell line NALM6 (IL-7 unresponsive) (F), or the T-ALL cell line HPB-ALL (IL-7 responsive) (G). Differences in leukemic burden were assessed using the unpaired Student t test. ∗P < .05; ∗∗P < .01.