Fig. 5.

PPD/polyIC induces bystander effects. (A) Low doses of PPD/polyIC eradicated LNCaP cells by the PBMC-mediated bystander effect. LNCaP-Luc cells were treated with PPD/polyIC at the indicated concentrations of polyIC. After 24 h, PBMCs (or medium) were added to the culture for 48 additional hours. The survival of LNCaP-Luc cells was measured by luciferase assay (Promega). (B and C) PPD/polyIC led to death of the untreated cells by combined direct and PBMC-mediated bystander effects. (B) LNCaP cells were treated with PPD/polyIC at the indicated concentrations of polyIC. After 16 h, PC3-Luc cells were added to the culture. PBMCs (or medium) were added 6 h later. The coculture was incubated for 72 additional hours. The survival of PC3-Luc was measured as above. (C) PC3-PSMA cells were treated with PPD/polyIC at the indicated concentrations of polyIC. After 16 h, MCF7-Luc cells were added to the culture. PBMCs (or medium) were added 6 h later. The coculture was incubated for 72 h longer and MCF7-Luc survival measured as above. The graphs show means plus SDs.