The recognition of HA by NKp46 is mediated through the membrane proximal domain (D2). Uninfected and SV-infected 721.221 cells were incubated with or without mAb against HA (135.7) or control mAbs (12E7 and TC-9A1) and stained with the indicated various fusion proteins followed by PE-conjugated goat antihuman antibodies. Figure shows one representative experiment of 20 performed. MFI indicates median fluorescence intensity. (A) NKp30-Ig. (B) NKp46-Ig. (C) NKp46D2-Ig. (D) NKp46D1-Ig. Error bars indicate SD.