Expression and cleavage of Bid in CD40-activated CLL cells. CLL cells were activated via coculture with HeLa cells (Control) or HeLa-CD154 cells and then isolated for further study. Twenty-four hours later, the CLL cells were treated for 12 hours with medium or CH11. Seventy-two hours later, the CLL cells were treated for 12 hours with medium, CH11, 1540-14, and/or zVAD-fmk, as indicated at the bottom of the figure. Protein lysates were prepared and normalized for total protein content. Cell lysate (30 μg) was applied to each lane of a polyacrylamide gel for immunoblot analyses with anti-Bid (top row) or anti-β-actin (bottom row), as indicated on the left side of the figure.