Inhibition of calcineurin blocks Ca⁺⁺-dependent induction of KSHV lytic protein expression.

BCBL-1 cells were stimulated with ionomycin (1μg/mL), thapsigargin (5 nM), or TPA (15 nM) in the presence of calcineurin or PKC inhibitors. After 3 days, viable cells (ie, Dead Red–negative cells) were examined for PF-8 (A, C) or gpK8.1 (B, D) expression. For experiments with calcineurin inhibitors (A, B): no inhibitors (▪), +0.5 μM CsA (■), +0.1 μM FK506 (▧). For experiments with PKC inhibitors (C, D): no inhibitors (▪), +10 nM SS (■), +1 μM BIM (▧). Data represent mean ± SEM of at least 3 separate experiments. *P < .01 compared to concurrent induction without inhibitor.