Figure 1.

Analysis of hemagglutinin (HA) expression. 293 T Lenti-X cells were transfected with HA expressing plasmid and stained at 24 h post-transfection for detection of HA on the plasma membrane as described in Section “Materials and Methods.” Cells were fixed and expression of HA was quantitatively measured by flow cytometry (A) or observed by confocal laser scanning microscopy (B). (A) The percentage of HA-expressing cells is indicated. The overlay line (green) represents the fluorescence distribution of cells stained only with the secondary antibody. (B) Images represent single central optical sections (a–c) and a 3D reconstruction (d). Nuclei are colored in blue by DAPI staining and green color represents membrane associate HA protein. Scale bars, 8 µm. Untransfected cells (a) were used as negative control. Results from one representative experiment are shown for each analysis.