Confocal fluorescence microscopy analysis of S100 and Lag expression by immature DCs differentiated from SP (CD7⁻45RA⁺), DP (CD7⁺45RA⁺), or CD34⁺CD1a⁻ thymic HPCs.

SP HPCs were cultured for 8 days under the standard condition, IL-4 being added from day 5 onward before DCs were sorted, based on high CD1a expression, and cytospun; DP and thymic HPCs were cultured and processed under the same conditions but without preliminary sorting (CD1a^hi DC more than or equal to 90% of day 8 cells). Images at 0.25 mm pixel size were obtained at × 40 magnification, 1.0 numerical aperture, and visualized in pseudocolor. Results are representative of 2 of 6 experiments.