Fig. 2: Siglec-6 mAbs show epitope-dependent receptor internalization properties.

a Siglec-6 internalization on hMCs after overnight incubation with the indicated Siglec-6 mAb clones as determined by flow cytometry using AK05 as the detection mAb. Data are representative of two experiments with two independent donors. b Heatmap of Siglec-6 receptor internalization levels induced by overnight incubation with Siglec-6 mAb clones (5 μg mL⁻¹) and their respective binding domains and bins. c Siglec-6 internalization on hMCs alone or in the presence of different ratios of THP-1 cells after incubation with 5 μg mL⁻¹ AK04 hIgG1 (orange) or isotype control (gray). d Siglec-6 internalization of hMCs alone or in the presence of THP-1 cells (1:3) after incubation with 5 μg mL⁻¹ of AK04 hIgG1 (orange), AK04 F(ab’)2 (hashed orange), AK02 hIgG1 (green), AK02 F(ab’)2 (hashed green), or isotype control (gray). e Siglec-6 expression on different MC populations from NSG-SGM3 humanized mice after intraperitoneal administration of 5 mg kg⁻¹ AK04 hIgG1 (orange), AK04 F(ab’)2 (hashed orange), AK02 hIgG1 (green), AK02 F(ab’)2 (hashed green), or isotype control (gray). Data are plotted as mean ± SD (three independent donors for Panel C and D; six mice/group for Panel E) and are representative of at least two experiments. **P < 0.01; ***P < 0.001; ****P < 0.0001 by two-way ANOVA with Šidák multiple-comparisons test.