Fig 2: iNKT Cells Induce IL-1ß Secretion by BMDCs during Infection with Microbes that Fail to Elicit Strong IL-1ß Release in a Cell-Intrinsic MannerBMDCs were infected with (A) B. fragilis or (B) C. trachomatis at increasing MOIs, washed, and cultured alone or with iNKT cells for 24 h in the presence of a FasL-blocking antibody (aFasL mAb) or an isotype control. IL-1ß release was quantified by ELISA. Error bars represent mean + SD of triplicate samples; panels are representative of three and two independent experiments, respectively.

Fig 3: iNKT Cells Employ the Death Receptor Ligand FasL to Instruct TLR-Primed BMDCs to Release IL-1ß(A) iNKT cells were cultured in the presence of increasing concentrations of plate-bound anti-CD3 for 24 h, after which their cell-free Supes were used to stimulate P3C-primed BMDCs for 24 h. IL-1ß (left) and interferon ? (IFN-?; right) in the Supes were quantified by ELISA. Nigericin-stimulated BMDCs were used as a control.(B) The ImmGen database was mined to compare the expression of cell-surface proteins (Gene Ontology term “cell surface,” GO0009986) expressed by iNKT cells versus other aß T cells. The red dots represent genes expressed by iNKT cells with a fold change of greater than 5 compared with all other aß T cells. Expression values comparing class means for specific T cell populations are shown in the right panel.(C) P3C-primed BMDCs were co-cultured with iNKT cells for 24 h in the presence of a FasL-blocking antibody (aFasL mAb) or an isotype control. IL-1ß release was quantified by ELISA. MSU-treated BMDCs were used as a control.(D) P3C-primed BMDCs from WT and Fas-/- mice were co-cultured with iNKT cells for 24 h. IL-1ß release was quantified by ELISA. MSU-treated BMDCs were used as a control.(E) Resting iNKT cells were stained with a FasL-specific antibody or an isotype control and subsequently analyzed by flow cytometry. The left panel represents surface staining, whereas the right panel represents permeabilized iNKT cells.(F) P3C-primed BMDCs from WT and CD1d-/- mice were co-cultured with CellTrace Violet-labeled-iNKT cells for the indicated times in the presence or absence of aGalCer, and the expression of FasL on the surface of iNKT cells was analyzed by flow cytometry. Numbers on the right of each histogram represent mean fluorescence intensity values.Error bars represent mean + SD of triplicate samples. Each panel is representative of at least three different experiments.