Preferential transformation of CD8α⁺ DCs is correlated with absence of Tg expression in DC precursors, increased Tg expression in CD8α⁺, and higher steady-state proliferation in CD8α⁺ DCs in Mushi1 and in WT mice. (A) Tg expression is barely detectable in bone marrow DC precursors. Bone marrow cells and CD11c⁺ magnetically purified splenocytes of indicated mice were analyzed for MHC-II and GFP reporter expression by FACS analysis. CD11c⁺ gated cells are shown. (B) Expression levels of GFP were analyzed in spleen DC subsets of healthy Mushi1 Tg mice as in panel A. For pDCs, the percentage of B220⁺ and/or GFP⁺ cells is indicated. For cDCs, the geometric mean of GFP level is shown in indicated regions of cells stained for CD11b or CD8α. (C) Expression levels of GFP were analyzed in epidermal LCs (gate: CD45⁺MHCII^high), migrated LCs (gate: CD11c⁺CD205^brightCD8α⁻), and dermal DCs (gate: CD11c⁺CD205^intCD8α⁻) in skin-draining LNs, and spleen CD8α⁺ cDCs from 3.5-month-old (Tg) and non-Tg (LM) mice. The percentage and the geometric mean (Geo) of GFP⁺ cells with the indicated gates are shown. (D) Spleen cells of control from Mushi1 healthy 2-month-old (Tg healthy) and non-Tg (LM) mice were purified and gated as in panel A. In the left part, the percentage of cells positive for CD8α and MHC-II expression are shown. In the right part, the gate positions are indicated. Steady-state proliferation of indicated DC subsets was determined by Hoechst staining. The percentage of S and 4N cells is indicated.