FIG. 4.

LMP-1-expressing cells upregulate STAT1 expression in cocultured LMP-1-negative cells. DG75 cells were transfected with 3 μg of pSG5 empty vector or 3 μg of LMP-1 expression vector and 3 μg of rCD2-EGFP expression vector. At 48 h posttransfection, transfected cells were magnetically selected using a monoclonal antibody against rCD2. Total lysates of the transfected (+) and nontransfected (−) cell populations were prepared and analyzed by SDS-PAGE and Western blotting using antibodies specific to LMP-1, STAT1, TRAF-1 (sc-875; SCB), and actin. BL41 and IARC-171 total lysates were included as negative and positive controls, respectively. The results shown are representative of three separate experiments.