Figure 8.

Simvastatin does not interfere with T cell function and enhances effects of immunotherapy in a mouse model of HER-2^pos breast cancer. (A) Example IFN-γ EliSpot wells from individual healthy donor Peripheral Blood Mononuclear Cells (PBMCs) stimulated with a mixture of common viral peptide recall antigens (left panel) or tetanus toxoid (right panel) in the presence or absence of simvastatin (“Simva”; 1–10 µM). (B) Composite analysis of each of the 3 donors for viral recall peptides (left panel) and 3 donors for tetanus toxoid (right panel). Statistical analysis by one-way ANOVA indicated no significant difference between simvastatin-treated and untreated groups. (C) IFN-γ ELISA analysis of 72 h culture supernatants from allogeneic Mixed Leukocyte Reactions (MLRs) where activated dendritic cells (DC) and lymphocyte-rich elutriation fractions were co-cultured at 1:40 stimulator:responder ratios in the presence or absence of 1–10 µM simvastatin. Data displayed represents the mean IFN-γ production from seven unique allogeneic DC:lymphocyte pairings. Statistical analysis by one-way ANOVA indicated no significant difference between simvastatin-treated and untreated groups (B.D. = below detection). (D) TUBO-bearing Balb/c mice, 7 days after implantation, were either left untreated (“No Rx”) or treated with Simvastatin (“Simva”), peptide-pulsed DC-based therapy (“DC”), or given combined treatment with simvastatin plus peptide-pulsed DCs (“Both”). Tumor size was measured periodically with calipers during treatment. Tumor size denoted as average area +/− SEM. Statistical significance is indicated by the asterisk (*). (E) TUBO cells were cultured in vitro with IFN-γ plus TNF-α, IFN-γ only, or no treatment in the presence of increasing concentrations of Simvastatin for 72 h, then assessed for metabolic activity by the Alamar Blue dye assay. (F) TUBO-bearing Balb/c mice, 7 days after implantation, were either left untreated (“No Rx”) or treated with Simvastatin (“Simva”), Interferon-γ (“IFN-γ”) or given combined treatment with simvastatin plus IFN-γ (“Both”). Tumor size was measured periodically with calipers during treatment. Tumor size denoted as average area +/− SEM. Statistical significance is indicated by the asterisk (*).