Cytolytic activity and IFN-γ production by TAP2^−/− NK cells after stimulation with mAbs against triggering receptors.

(A) Effector cells were analyzed in a redirected killing assay against the FcγR⁺ P815 target cells in the absence (CTR) or in the presence of the following mAbs: BAB281 (IgG1, anti-NKp46); AZ20 (IgG1, anti-NKp30); Z231 (IgG1, anti-NKp44); PP35 (IgG1, anti-2B4); MA152 (IgG1, anti-NKp80); c127 (IgG1, anti-CD16); BAT221 (IgG1, anti-NKG2-D), and c218 (IgG1, anti-CD56). In this representative experiment, the polyclonal NK cell populations derived from the 2 patients (E.M.O. and E.F.A.) and 2 healthy donors (A.M. and C.B.) and 4 clones from E.M.O. (TAP1, TAP3, TAP4, TAP5) are shown (similar results could be obtained with E.F.A. clones). NK clones displayed the following phenotypes: TAP1 (NCR^bright 2B4⁺NKp80⁺), TAP3 (NCR^bright 2B4⁺NKp80⁺), TAP4 (NCR^dull 2B4⁺NKp80⁺), TAP5 (NCR^dull 2B4⁺NKp80^dull). The E:T ratio used in this experiment was 4:1. (B) The same polyclonal NK cell populations were assessed for IFN-γ production either in the absence of stimulation (CTR) or after stimulation with each of the following mAb: c218 (IgG1, anti-CD56, 3μg/mL), BAB281 (IgG1, anti-NKp46, 3 μg/mL), c127 (IgG1, anti-CD16 0.5 μg/mL).