Apaf-1 expression and the sensitivity to UV light–induced apoptosis in the human AML blasts.

(A) Western blot analysis of the expression of Apaf-1 in human normal CD34⁺ cells and AML blasts. 50 μg protein was used for Apaf-1 expression. Monoclonal anti–Apaf-1 antibody was used at 1:500 dilution. (B) UV light–induced apoptosis. After exposure to UV light for 5 minutes and further culture for 10 hours, cells were fixed with 4% paraformaldehyde and permeabilized by 0.05% saponin for 20 minutes. Slides were stained with 50 ng/mL DAPI. Apoptotic cells were counted under a fluorescence microscope.