The production of IFN-γ by cDC subset preparations in relation to contamination with cells bearing NK markers. cDCs were isolated as outlined in Figure 1, either by standard procedure or with additional NK cell marker depletion. (A) Analysis of the content of CD49b⁺ CD11c^int IKDCs within different cDC preparations, beginning with the enriched standard cDCs, the enriched cDCs with additional NK-marker depletion, the CD4⁻8⁻ fraction of the NK-depleted cDC preparation without the normal gating for CD11c, and the final sorted, NK-marker–depleted and CD11c^hi-selected CD4⁻8⁻ cDC preparation. (B) The production of IFN-γ in the supernatant following culture of 10⁵ cells of each fraction in 0.2 mL medium with IL-12, IL-18, and CpG 1668, as in Table 1. The cDC samples were as analyzed in panel A, with contamination of NK-marker–depleted CD4⁻8⁻ cDCs being less than 0.001%. IKDCs were isolated and sorted from enriched pDCs as CD45RA⁺ CD11c^int CD49b⁺ cells, as shown in Figure 2. NK cells were CD49b⁺ cells directly sorted from a spleen suspension. Results are a single experiment typical of 3 showing the mean of 4 cultures plus or minus the standard deviation (SD). The broken line gives the threshold for detecting the production of IFN-γ above the background.