Phagocytosis of FITC-labeled dextran particles by DC treated with or without TNFα. Although TNFα-treated DC displayed a lower degree of phagocytosis on a per cell basis as measured by fluoresence intensity, the overall percentages of DC capable of dextran particle uptake were equivalent between DC cultured with or without TNFα. DC were incubated for the indicated periods at 4°C (○) or 37°C (•) with FITC-dextran of varying molecular weights. DC were washed free of unbound particles and were then analyzed by FACS, as described in the Materials and Methods. Data are expressed as mean fluorescence channel (MFC) calculated by FACS computer software.