Figure 5.

NKG2D- and DNAM-1 Mediated TCR-Independent Cytotoxicity of re-iNKT Cells

Parental CD4⁺ iNKT cells and re-iNKT cells were stimulated with irradiated PBMCs pulsed with α-GalCer in the presence of rhIL-2 and rhIL-15 and then expanded and used for the assays.

(A) Cytotoxicity of re-iNKT cells and parental CD4⁺ iNKT cells toward autologous vehicle DCs and α-GalCer DCs at the indicated E/T ratios.

(B) Cytotoxicity of re-iNKT cells and parental CD4⁺ iNKT cells toward K562 and U937 cells at the indicated E/T ratios.

(C) Expression of cytotoxicity-related molecules in IL-2-pretreated re-iNKT cells or parental iNKT cells. Expression of the indicated molecules (open) and isotype-matched controls (filled) is shown. The MFI of each molecule is shown in the upper right corner.

(D) Cytotoxicity toward the indicated tumor cell lines at an E/T ratio of 2.5:1 was tested in the presence of the indicated Abs blocking receptor/ligand interactions or after pretreating re-iNKT cells with 10 nM concanamycin A (CMA) to block perforin.

(E) CD96 and TIGIT expression. Re-iNKT cells or parental iNKT cells were stimulated with plate-bound control IgG or anti-CD3 mAb (10 μg/ml). Expression of the indicated molecules (open) and isotype-matched controls (filled) is shown. The MFI of each molecule is shown in the upper right corner.

In (C) and (E), one representative result from two to three independent experiments is shown. In (D), data were run in triplicate, and experiments were repeated twice; the results of one representative experiment are shown. Error bars depict mean ± SD.