Fig. 1: Transduction of primary AML cells and IL-1RAP cell surface expression.

a Upper: representative flow cytometric analysis of AML primary cells from blood. The IL-1RAP histogram is shaded dark gray. Relative fluorescence intensity (RFI) is provided and calculated relative to the intensity of IgG1 isotype staining (light gray). Blast cells were characterized and discriminated from monocytes by their CD45+CD34+CD38+CD14− phenotype in flow cytometry. Lower: distribution of primary blasts from AML patients (n = 30) in 3 groups according to the intensity of their cell surface IL-1RAP staining (RFI). 1 ≤ RFI low ≤ 2 (n = 9); 2 < RFI inter ≤ 3 (n = 13); 3 < RFI high (n = 8). b Representative cytometry gating analysis of the transduction efficiency of primary AML blast cells with the mock or CAR lentiviral vector carrying the ∆CD19 gene. After 48 h of transduction, untransduced or transduced cells were stained with anti-CD19-APC and the percentage of CD19+ cells was measured by flow cytometry. Blasts were gated on CD45+ cells and then discriminated from T cells and monocytes. c Results of transduction efficiency of primary AML cells are presented as percentage mean ± SD of seven independent experiments from six independent starting AML samples. d Upper: detection of IL-1RAP expression on the surface of primary AML cells. Untransduced or transduced (mock or CAR) cells were stained using anti-CD19-APC and anti-IL-1RAP-FITC and evaluated by flow cytometry. An isotype-matched IgG was used as a negative control. d Lower: relative fluorescence intensity of IL-1RAP cell surface expression, AML primary blasts of 6 patients (3 low and 3 high IL-1RAP expresser primary blasts) untransduced (blue circles), or transduced with either mock (green squares) or IL-1RAP CAR (red triangles) vectors. **p < 0.01.