HSPG and FcR cross-linking impair DC generation. (A) Peripheral blood monocytes were cultured in GMCSF/IL-4 in the presence of 10 μg/mL of the indicated reagents. After 6 days, the number of viable DCs in the culture was assessed by dye exclusion; 100% was arbitrarily defined as the number of DCs recovered from culture with medium alone. Error bars represent SD. (B) Binding of 10 μg/mL ACRP-APRIL on monocyte-derived DCs. ACRP alone served as a negative control.