Recombinant Vaccinia Viruses Coding Transgenes of Apoptosis-Inducing Proteins Enhance Apoptosis But Not Immunogenicity of Infected Tumor Cells

Figure 3

Apoptosis analysis of infected cells. (a) Cells were treated with recombinant VVs (0.05 and 0.5 PFu/cell) for 12 and 36 h and then stained using annexin V/propidium iodide (PI). The stained cells were assayed for apoptosis by flow cytometry. Bar graphs summarized the percentage of apoptotic cells from three independent experiments (, ). dGF-VV-GMCSF-dGF, Lact-VV-GMCSF-Lact, and Apo-VV-GMCSF-Apo. (b) Electrophoretic analysis of DNA fragmentation (C: nontreated cells, 1: VV-GMCSF-dGF, 2: VV-GMCSF-Lact, 3: VV-GMCSF-Apo, and M: DNA marker). MDA-MB-231 cells were treated with VVs (0.05 PFU/cell) for 72 h and then DNA samples were isolated. Data are representative of at least two independent experiments. (c) Western blot analysis of cyclin B1 in MDA-MB-231 cells. The quantification of the digital images was performed using Gel-Pro Analyzer software. Data are presented as mean ± SD (). (d) The percentage of the MDA-MB-231 cells with active caspase-3 and caspase-7 in VV-treated cells. Cells were infected with recombinant VVs (0.05 PFU/cell) for 12, 24, and 36 h and then analyzed by flow cytometry as described in Materials and Methods. FAM-positive cells (%) were calculated as the difference between experimental sample and control sample. The data represent the mean ± SD, independent experiments. difference between groups was statistically significant at .