The effect of dynasore and EIPA on dextran and transferrin uptake HeLa cells (grown on glass cover slips) were incubated at 4uC for 1 hr with 50 mg/ml Alexa633-labeled Transferin (InVitrogen) in PBS. After 1 hr the medium was replaced by PBS or PBS supplemented with 10% FCS containing IAV (strain WSN; MOI 10) and 0.5 mg/ml FITC-Dextran (Sigma; 70 kDa) and cells were transferred to 37uC for 15 min. After 15 min cells were fixed and stained as described above and examined by confocal microscopy.