Characterization of B7-H6. (A) Direct interaction of B7-H6 with NKp30 using SPR. The data show binding of soluble DKFZp686O24166-Fc to immobilized NKp30-Fc in the presence or absence of blocking anti-NKp30 mAb (1849 and AZ20). Data are representative of three independent experiments. (B) Protein sequence encoded by the B7-H6 gene. Predicted signal peptide, IgV, IgC, and transmembrane domains are indicated. (C) Schematic representation of the B7-H6 and the NKp30 gene orgnaization compared with members of the B7 and the CD28 families, respectively. Each domain is represented as a box and is encoded by exons that are separated by phase 0, 1, or 2 introns as indicated. The scheme refers to the “canonical” sequence as defined by www.uniprot.org. (D) The data show SPR experiments using soluble B7-H1-Fc, B7-H3-Fc, 4IgB7-H3-Fc, B7-H6-Fc, and B7-DC-Fc and immobilized NKp30-Fc. RU, relative units. Data are representative of two independent experiments.