FIG. 6.

Short-term induction of C/EBPα expression in U937 cells is sufficient for morphological granulocytic maturation. C/EBPα-transfected U937 cells (clone U937α#2) were cultured in the absence (A) or continued presence (B) of zinc for 16 days. The same cell line was also initially seeded in medium containing zinc, subsequently washed after 1 day (E and F), 2 days (D), or 3 days (C), and maintained in zinc-deficient medium for an additional 20 days (C), 21 days (D), 22 days (E), or 23 days (F).