Comparative analysis of apoptosis induction in promyeloleukemic HL-60 cells using rGal-1 and Gal-1hFc. A, HL-60 cells were incubated with rGal-1 in the presence or absence of DTT and/or 50 mM lactose. Cell death analysis (Annexin V staining/PI uptake) was evaluated by flow cytometry at 4 and 24 h after incubation. B, Graphical representation of data from three different experiments depicting mean Annexin V+ staining/PI+ uptake values (±SD). *Statistically significant difference compared with no DTT control, p ≤ 0.01. C, HL-60 cells were incubated with Gal-1hFc or dmGal-1hFc in the presence or absence of 50 mM lactose. D, Graphical representation of data from three different experiments depicting mean Annexin V+ staining/PI+ uptake values (±SD) at 4 and 24 h after incubation. *Statistically significant difference compared with hFc control, p ≤ 0.01.