1. Cool MACS magnet adaptor, LS column, MACS Buffer, and PBS at 4 °C. 2. Dilute blood 1:1 in PBS, add 15 ml histopaque-1077 to a 50 ml conical tube. 3. Layer 30-35 ml blood/PBS on top, spin at 800 x g for 20 min at RT, no brake. 4. Collect WBC at interphase using a Pasteur pipette, avoid aspirating histopaque-1077. 5. Pellet cells at 300 x g for 10 min (RT), wash in cold PBS at 300 x g for 10 min, add 50 ml PBS. 6. Count cells, dilute if needed, take a sample for pre-sort control for FACs analysis. 7. Centrifuge at 300 x g for 10 min (RT), re-suspend pellet in 300 µl MACS buffer per 10^8 cells, add 100 µl FcR Blocking reagent and 100 µl Microbead dendritic antibody cocktail. 8. Incubate for 10 min at 4 °C, transfer to 50 ml Falcon, wash in PBS, spin at 300 x g for 10 min (RT). 9. Charge the LS column with 3 ml MACS buffer, discard flow-through. 10. Re-suspend cells in 500 µl MACS buffer per 10^8 cells, add to column, collect flow-through, re-apply flow-through, wash column twice with 3 ml washes, collect dendritic cell population. 11. Count cells, use for downstream applications. 12. For FACS staining, pellet 10^5 cells at 400 x g for 5 min, re-suspend in residual PBS, add 1 µl normal mouse serum, incubate for 10 min (RT). 13. Add directly conjugated antibody, stain for 20 min (RT) in the dark, wash cells in PBS, spin at 400 x g for 5 min (RT), re-suspend in 500 µl, proceed to FACS analysis.