Fig. 5

CDK4/6 inhibitor-treated KSHV⁺ cells and EBV⁺ cells express increased ICAM-1 and B7-2 and induce increased T-cell activation. a, b Surface expression of ICAM-1 and B7-2 in BCBL-1 cells treated with 0.1 μM or 0.3 μM Abe (a) and Akata cells treated with 0.5 μM or 1 μM Abe (b) for 72 h. Cells were then harvested, and stained with PerCP/Cy5.5-conjugated IgG isotype control, anti-ICAM-1, or anti-B7-2 antibodies and analyzed using flow cytometry. Shown are fold changes in median fluorescent intensity (MFI) of one experiment of Abe-treated cells over untreated control cells. c–f T-cell activation in BCBL-1 (c and d) and Akata (e and f) cells in response to Abe treatment in the same experiment analyzed in panels a and b. Treated cells were washed with PBS to remove Abe and coincubated for 6 h with Jurkat cells expressing luciferase under the control of the IL-2 promoter at a 2:1 (BCBL-1) or 1:2 (Akata) target to effector ratio in the presence of anti-human CD3 antibody to measure Jurkat T-cell activation. Activation of the Jurkat T-cells are shown as relative light units (RLU) (c and e). Average fold changes in RLU from Jurkat cells coincubated with Abe-treated BCBL-1 and Akata cells over those coincubated with ethanol control (0 μM Abe) treated cells in the presence of 0.6 μg/mL anti CD3 antibody are shown in d and f. Error bars represent standard deviations from 3 independent experiments. Statistically significant differences (*p ≤ 0.05, paired 2-tailed t-test) between control and Abe-treated cells are indicated