Effect of apoptotic tumor cells combined with transgenic CD40L expression on immune-mediated tumor protection.

Apoptotic tumor cells combined with transgenic CD40L expression produce immune-mediated tumor protection. Mice were vaccinated twice with apoptotic MPC-11 (A), S107 (B), or X-24 (C) cells mixed with CL7.1/mCD40L fibroblasts and challenged 2 weeks later at a distant site with live plasmacytoma cells. Transgenic expression of CD40L (broken lines) significantly increases tumor-free survival compared with controls (solid lines) for all plasmacytoma cell lines. Data are representative of 8 animals for each group for the MPC-11 and S107 cell lines. For the X-24 cell line, the data are representative of 8 animals for the control group and 15 animals for the vaccinated group.