Fig. 4

Induction of cell division by anti-4-1BB scFvs. To measure cell division, purified T cells were labeled with CFSE and treated as described in the Materials and Methods section. After 72 h of treatment, the T cells were stained with CD3 and analyzed for CFSE levels via flow cytometry. Representative data show the % division and are representative of three independent experiments. The decrease in the mean fluorescence intensity of the CFSE-labeled cells was observed in cells treated with anti-4-1BB scFvs, which indicates that cell division had taken place. No division was observed in cells treated with ES1 and control (p < 0.05)