Recombinant Human Cytomegalovirus (HCMV) RL13 Binds Human Immunoglobulin G Fc
Figure 5
RL13 binds and internalizes Fcγ.
ARPE-19 epithelial cells were transfected with RL13-YFP (green) and allowed to recover for 48 h. Cells were placed on ice 5 min before adding DyLight 649-conjugated human IgG Fc fragment (red) and incubated on ice for 30 min. Then, cells were washed and A: immediately fixed, B: shifted to 37°C for 30 min, or C: shifted to 37°C for 90 min before proceeding to fixation and confocal analysis. Rab5 (purple) was revealed by specific antibodies after permeabilization of the samples. Examples of co-localization between signals are indicated by white arrows. Orthogonal projections of the optical sections acquired from Z-stack are shown. White arrows indicate examples of co-localized spots. Fluorescent Fcγ was absent on the membrane of ARPE-19 cells transfected with empty expression vector used as control and no staining was detected following 30 min switch at 37°C (data not shown).