Isolation of blood DCs.

This study was approved by the ethical committee at the Karolinska Institutet, Stockholm, Sweden, and the NIH, Bethesda, MD, USA. Our sorting procedures for direct isolation of DCs from blood have been described previously (Lore et al., 2003, 2005, 2007; Smed-Sorensen et al., 2005). DCs were cultured in complete medium composed of RPMI 1640 and 10 % fetal calf serum (FCS; Sigma-Aldrich). To maintain viability, the medium for PDCs and MDCs was supplemented with interleukin (IL)-3 (1 ng ml⁻¹; R&D Systems) or granulocyte–monocyte colony-stimulating factor (GM-CSF, 2 ng ml⁻¹; PeproTech), respectively.