FIG. 1.

Downregulation of TCR/CD3 from the surfaces of U24-expressing Jurkat cells. (A) Jurkat cells were transiently transfected with a bicistronic transcript encoding several HHV-6A gene products (U4, U21, U24, U61, U78) and EGFP. Twenty-four hours posttransfection, surface CD3ɛ in cells displaying GFP expression was analyzed by flow cytometry. (B) Jurkat cells were transiently transfected either with a bicistronic transcript of U24 and EGFP (U24/EGFP) or with EGFP alone. Cells were collected after 24 h, stained for surface CD3ɛ or αβ TCR, and analyzed by flow cytometry. (C) Jurkat cells were transiently transfected with U24/EGFP, collected after 24 h, and stained with antibodies for the indicated cell surface receptors. (D) Jurkat cells were transiently transfected with U24/EGFP or EGFP alone and collected after 24 h. (Left) Cells were fixed and permeabilized to stain for total CD3ɛ and were then analyzed by flow cytometry. (Right) Percentage of CD3 remaining in U24-expressing cells compared to that in EGFP controls. Data used in this analysis were from the mean fluorescence of cells stained with PE-conjugated anti-CD3ɛ antibodies gated on EGFP-expressing cells. Data compiled from at least three consecutive independent experiments were analyzed.