Roles for Id2 in ex vivo generation of pDCs and CD103⁺ DCs. CD45.1⁺ BM cells from Id2^−/− or Id2^+/+ chimeric mice were cultured with GM-CSF or Flt3L for 6 days, as indicated. The proportion and absolute number of pDCs (A) and CD103⁺ DCs (B) were determined by flow cytometry and enumeration. Surface expression of SiglecH on pDCs derived from Flt3L cultures (A) and MHC II on CD103⁺ DCs derived from GM-CSF cultures (B) was analyzed to confirm cell identity; similar expression patterns were observed in GM-CSF (SiglecH on pDCs) or Flt3L (MHC II on CD103⁺ DCs) conditions (not shown). Results represent data from 3-6 independent experiments. DC numbers shown are mean ± SEM values of 3-6 independent experiments.