Figure 6.

Inhibition via NKG2A is effective when a high level of HLA-E is present. (A) U266 cells were pre-incubated for 2 h with HLA-B7 peptide, HLA-A1 peptide, DMSO, control peptide (non-HLA-E binding), or medium. HLA-E expression of U266 is depicted in the histogram, with its corresponding median fluorescence intensity (MFI). (B) Spontaneous degranulation of IL-2 activated natural killer (NK) cells cultured for 13 h in the absence of target cells. (C) Degranulation of NK cells upon 13 h co-culture with peptide- or control-incubated U266 target cells. Degranulating NK cells were denoted as CD107a+ NK cells. Each dot in the graphs represents the average of a technical replicate for an individual donor. Error bars in (B) indicate SD. n = 3 different NK cell donors.