FIG. 4.
Ectopic expression of VP22 complements ΔUL49 virus in the inhibition of antigen presentation following an HSV-1 infection. (A) VP22-expressing HEK293-CD1d (VP22/GFP) and control (GFP) cells were mock infected (gray-filled histogram), or infected with ΔUL49 (solid line) or UL49R (dotted line) for 6 h at an MOI of 5. The cells were fixed, permeabilized with 0.1% saponin, stained with an anti-HSV antibody, and analyzed by flow cytometry. (B) The same mock-treated or virus-infected cells were also fixed, stained with the CD1d-specific mAb 42.1 and analyzed by flow cytometry. (C) Aliquots of cells used in (A, B) were fixed and cocultured with human NKT cells (105/well, E:T = 1:1) for 48 h. Data are shown as the percentage of GM-CSF production compared with mock (set at 100%). Representative data from three independent experiments are shown. *p < 0.05; **p < 0.01 (Student's t-test).