Characterization of anti-B7-H6 mAbs. (A) P815.B7-H1, P815.B7-H6, or HeLa cells were stained with 4E5.5, 9G9.2, 10E2.9, or 17B1.3 anti–B7-H6 mAbs and analyzed by flow cytometry. mIgG1 was used as isotype control. Graphs are representative of at least 3 experiments. (B) NKp30⁺ DOMsp30 reporter cells were cocultured with P815.B7-H6 cells in presence or absence of anti–B7-H6 mAbs. DOMsp30 cell activation was determined by evaluating IL-2 production in the coculture supernatant in a standard CTLL-2 survival assay. Data are representative of 3 independent experiments. ***P < .001. (C) SPR analysis: Superimposed sensorgrams showing the injections onto NKp30 chip of soluble recombinant B7-H6 alone or preincubated with anti–B7-H6 mAbs. Sensorgrams were normalized in the y-axis and aligned in the x-axis at the end of injection. Sensorgrams are representative of 2 independent experiments. a.u., arbitrary unit; mIgG1, mouse IgG1.