Influence of sCD40L at different concentrations on surface phenotype.

L3055 (wild-type) cells were cultured for 3 days as for Figure 3 with concentrations of sCD40L shown and stained and analyzed by FACS for surface antigens indicated as described in “Materials and methods.” Negative (control) staining is indicated by unshaded black line. Shaded histogram is basal level of antigen expression for cells cultured in medium alone; with concentrations of sCD40L in culture: olive green = 0.4 ng/mL; red = 2 ng/mL; light blue = 10 ng/mL; purple = 50 ng/mL; blue = 250 ng/mL; green = 1250 ng/mL. Histograms shown are representative of at least 5 similar experiments.