FIGURE 2.

VentX overexpression promotes THP1 cell differentiation toward dendritic cells. A, THP1 cell lines expressing GFP or GFP.VentX under the control of tetracycline-inducible promoter were treated with 1.0 μg/ml doxycycline (DOX) for 10 days. Cell numbers at indicated days were counted and plotted. B, cell cycle profiles of THP1 cells expressing GFP or GFP.VentX after 10 days exposure to DOX. Cells were stained with propidium iodide and analyzed by flow cytometry. C and D, THP1 cells were treated with DOX for 3 days and harvested. The mRNA level (C) and protein level (D) of p21, NFκB, and c-Myc were analyzed by real-time PCR and Western blot, respectively. E and F, THP1 cells were treated with DOX and cultured under conditions described under “Experimental Procedures” to induce dendritic cell differentiation. E, 2 days after treatment, cells were harvested to analyze the surface expression of indicated antigens by flow cytometry. F, cells were photographed using phase contrast microscopy to show the morphological changes of VentX-expressing cells. Results shown are representative of at least three independent experiments.