Expression of EphA and EphB protein is regulated during DC differentiation. Time-kinetics of EphA and EphB expression during CD34⁺-derived DC culture from day 6 to day 14. Flow cytometric analysis was performed on cord blood CD34⁺ progenitors, cultured in the presence of GM-CSF and TNF-α until day 12, and after 24 hours and 48 hours of LPS activation. Cell surface EphA and EphB expression was followed by staining with biotinylated ephrin-A3-Fc and ephrin-B3-Fc chimera, respectively. As a positive control, DC maturation was followed by CD80/CD86 staining using biotinylated CTLA4-Fc chimera. Staining was revealed by PE-conjugated streptavidin. The percentages of CTLA4-Fc-, ephrin-A3-Fc-, and ephrin-B3-Fc-positive cells are indicated. Dotted-line overlay histograms show nonspecific staining with Fas-Fc chimera. Results are representative of FACS analysis of 3 independent samples.