Figure 4.

fcr-1 is readily detected on the cell surface of MCMV-infected cells and surface resident MULT-1 is rapidly recycling. (a) (10)1 cells were mock infected or infected with 5 PFU per cell of WT MCMV or Δm138/fcr-1. 15 h p.i., the cells were surface stained and intracellularly stained with mouse IgG Fc fragment and Cy5-labeled anti–mouse IgG. (b) Confocal analysis was performed on MULT-1–3T3 cells Ab-tagged for surface MULT-1 (red) as described for the uptake assay. Transferrin-FITC (green) was added in parallel with anti–MULT-1 mAb.