Figure 4.

CD33-specific nanoCAR T cells are cytotoxic against CD34⁺ HPC: (A) CD33 expression on CD34⁺ HPC isolated from cord blood. CD34⁺ HPC were isolated from cord blood and stained for CD45, CD33, CD34 and CD38. Cells are gated on CD45^dimSSC^lo and CD34⁺CD38⁻, CD34^dimCD38^dim and CD34⁻CD38⁺. Plots are representative for 5 donors; (B) Cytotoxicity in time. NanoCAR T cells were incubated with CD34 HPC for 72 h. CD38 and CD33 expression on CD34⁺ HPC measured at the start (zero hour) and the end (72 h) of the experiment; (C) Cytotoxicity in time. NanoCAR T cells were incubated with CD34 HPC for 72 h. At distinct time points, we measured the presence of T cells and HPC (gated on CD3⁻) by flow cytometry. Data points shown are the means, and error bars represent the SEM taken from a representative experiment. The experiment was performed two times, each time with two different donors.