Figure 5
Differences in the surface levels of pIN-fusion proteins determined by flow cytometry. HEK293 cells transfected with no cDNA (mock, panel A and B), pIN-G (panel C and E) or pIN-TGN (panel D and F) were subjected to FACS analysis either with (panel B, E and F) or without (panel A, C and D) anti-HA antibody followed by detection with Cy5-conjugated goat anti-mouse IgG1 (Methods). Calculated mean fluorescent intensity (MFI) values determined the background fluorescence (panel A) and non-specific antibody binding (panel B) of mock transfected cells. Panel C and D demonstrate the specific GFP fluorescence of pIN-G or pIN-TGN transfected cells respectively (quadrant R5), whilst surface labeling of transfected cells, with anti-HA and Cy5 primary and secondary antibodies reveal a cell population displaying both red and green fluorescence (panels E and F, quadrant R4).