Natural Killer Dendritic Cells Enhance Immune Responses Elicited by α-Galactosylceramide-Stimulated Natural Killer T Cells
Figure 4
NKDCs are required for an optimal immune response in NK cells, NKT cells, and DCs. CD11c-DTR Tg recipient mice were i.p. injected with DT (120 ng/mouse) to remove the CD11c+ DC population. After one day, 1.5 × 106 DCs (either total DCs or NKDC-depleted DCs) from WT mice were i.v. transferred to DC-deficient recipient mice. Eighteen hours later, splenocytes from both NKDC+ and NKDC− mice were stained with mAbs for flow cytometry. (a) The percentage of the IFN-γ-producing population among NK1.1+CD3−CD11c− NK cells and NK1.1+CD3+CD11c− NKT cells was plotted. The mean values ± SD are shown (, , ). (b) The percentage of the TRAIL-producing population among NK1.1+CD3−CD11c− NK cells and NK1.1+CD3+CD11c− NKT cells was plotted. The mean values ± SD are shown (). (c) The mean fluorescence of CD86 on CD11c+CD3−NK1.1− DCs was plotted. The mean values ± SD are shown (, ). (d) NKT cells (6 × 105 cells/well) were co-cultured with 2 × 105 DCs (either total DCs (NKDC-included) or NKDC-depleted DCs pulsed with PBS or α-GC) in either the presence or the absence of anti-IFN-γ mAb. (e) For the transwell assay, 6 × 105 NKT cells and 2 × 105 DCs as described above were plated in a lower and an upper chamber, respectively, in either the presence or the absence of anti-IFN-γ mAb. After 72 hours of co-culture, CD69 expression of NKT cells was examined by flow cytometry. Representative results from two independent experiments are shown.