Expression of constitutively active PKB enhances IL-1β secretion. THP-1 cells were virally transduced with either a control vector (eGFP) or a constitutively active form of PKB (PKBcaax). (A) Wild-type and transduced THP-1 cells were serum-starved overnight, after which cell extracts were prepared by adding lysis buffer to the cell pellets. Cell lysates were assayed for phospho-PKB, phospho-eIF4B, phospho-GSK-3, phospho-S6, PKB, and actin content. (B) Transduced THP-1 cells were incubated with simvastatin for 24 hours, followed by a 4-hour stimulation with LPS. Release of IL-1β was determined by ELISA; data are mean plus or minus SEM (n = 6; *P < .05). (C) Wild-type THP-1 cells were cultured for 24 hours in the presence or absence of simvastatin (10 μM) and stimulated for an additional 4 hours with 200 ng/mL LPS. PKB inhibitor was added 1 hour before simvastatin treatment at the concentrations indicated. Release of IL-1β was determined by ELISA; data are mean plus or minus SEM (n = 3; *P < .01).