Analysis of cut/CDP protein expression during monocyte to macrophage maturation. Western blot analysis was performed on whole cell extracts (50 μg) from day 0, 3, and 7 monocyte culture (lanes 5 through 7) incubated with a specific anti–cut/CDP antibody. Whole cell extracts (50 μg) from U937 cells undifferentiated or induced to monocyte differentiation with 125OH-vitamin D₃ for 2, 3, and 4 days (lanes 1 through 4) and HeLa cells (lane 8) were used as positive control for cut/CDP expression.