Enrichment methods for porcine pDC: purity and impact on pDC activation by FMDV. A. CD172a/CD4 plot of unsorted PBMC, CD172a-enriched PBMC, CD14-depleted and subsequently CD172a-enriched PBMC, CD3-depleted and subsequently CD4-enriched PBMC. pDCs were gated based on their CD4highCD172alow phenotype, and their percentage is indicated. B and C. IFN-α responses of PBMCs and sorted populations shown in (A). The cells were stimulated for 24 h at 39°C with 10 μg/mL of CpG D32, medium (B), or FMDV O UKG 2001 at a MOI of 5 TCID50/cell (C). IFN-α in the supernatants was detected by ELISA. The bars represent the mean value of triplicates and the errors bars show the standard deviation. The data are representative for two independent experiments.