The lysis of YAC-1 target cells by components of DC preparations. The freshly sorted cells were cultured at various concentrations for 4 hours at 37°C with 10⁴⁵¹Cr-labeled YAC-1 cells. (A) The lack of cytolytic activity by the CD172a⁻ cells within the CD4⁻8⁻ cDC preparations (DN Sirpα⁻). These cells were isolated as in Figure 4A, and compared with the CD4⁻8⁻ CD172a⁺ cDCs (DN Sirpα⁺) and to NK cells. The mean plus or minus SD of 3 experiments is presented. (B) The cytolytic activity of IKDCs, sorted from the pDC preparations as CD49b⁺ CD11c^int CD45RA⁺ cells (both CD45RA^hi and CD45RA^int), as in Figure 2A. One experiment is presented; a second experiment gave similar results.