FIG 1.

HSV-1 infection of human corneal epithelial cells increases syndecan-1 shedding. (A) Syndecan-1 expression is decreased on the HCE cell surface at different time points postinfection, measured using flow cytometry. Cells were infected with KOS-WT at an MOI of 0.1 and were stained for syndecan-1 at 24 and 36 hpi. (B) Fluorescence intensity measurements based on flow cytometry results. Integrated mean fluorescence intensity of the whole cell population was measured, and fold change was normalized to uninfected mock samples for each time point. (C, left) Syndecan-1 expression on the cell surface is decreased in primary human corneal epithelial cells. Cells were infected with 17-GFP at MOI 0.1 and were stained for syndecan-1 at 48 hpi. Mean fluorescence intensity (MFI) values for the uninfected and infected cells were 122,353.86 and 66,945.33, respectively. (C, right) Dot plot of the flow cytometry results. Q1 and Q2 represent FITC-positive populations (infected). Q2 and Q3 represent syndecan-1-positive populations (right). (D) Fluorescence intensity measurements based on flow cytometry results. Integrated mean fluorescence intensity of the whole cell population was measured using flow cytometry at 36 hpi. Uninfected and 36-hpi samples are compared. (E, left) Immunofluorescence microscopy images show decreased expression of syndecan-1 on the cell surface of infected cells. HCE cells were grown on imaging dishes and infected with KOS-WT at an MOI of 0.1 for 24 h. The cells were stained for syndecan-1 (red) and 4′,6-diamidino-2-phenylindole (DAPI) (blue). Merged images of syndecan-1, DAPI, and brightfield microscopy are also shown. (E, right) Images were quantified for syndecan-1 intensity. A hundred cells were picked at random for each sample, and the intensity of syndecan-1 was measured for each cell using ImageJ.