CIITA affects Tax-2 subcellular localization. 293T cells were transiently transfected with the indicated vectors (GFPCIITA, Tax2-V5). Eighteen hours post transfection, cells were treated (B) or not (A) with leptomycin B (20 nm) for 3 hours. Cells were then washed, fixed, and stained with anti-V5 IgG2a monoclonal antibody for the detection of V5-tagged Tax proteins (Ab, Ad, Bb, Bd). GFPCIITA positive cells are shown in Aa, Ac, Ba, Bc. Merged images are shown in Ae, Be. The images were analyzed by a laser scanning confocal microscope.