Purification, homing, and in vivo proliferation of donor pDCs after allogeneic transplantation. (A) Gating strategy for sorting both HSCs and pre-pDCs from mouse bone marrow. After initial scatter-based gating to exclude doublets, the B220+ and B220− populations were identified and further gated for pre-pDC and HSC sorting, respectively. Pre-pDCs were defined as B220+, lineage 1− (lineage 1 = CD3, CD11b, CD19, CD49b, IgM, and Ter119), CD11c+, and PDCA1+. Postsort analysis is shown in the top right plot. HSCs were defined as lineage 1− (with less stringent gating than used for the pDC sort), lineage 2− (lineage 2 = CD4, CD8, GR-1, and I-Ab), Sca-1+ and C-kit+. Postsort HSC analysis is shown in the third plot, bottom row. Analysis of CD4 and CD8 content of T cells purified by negative immunomagnetic selection (without prior gating) is shown in the bottom right plot. (B) Bioluminescent imaging images of pDCs trafficking in syngeneic and allogeneic recipients. FVB (H-2q; n = 5) and BA.B10 (CD90.1+, H-2k; n = 5) recipients were lethally irradiated and injected with pre-pDCs sorted from L2G85 luciferase+ mice in combination with FVB HSCs and T cells. Bioluminescent imaging images were taken weekly; representative images are shown. The abdomens of black-furred B10.BR allogeneic recipients (bottom panels) were depilidated with Nair before bioluminescent imaging.