Morphologic features of mature DCs in serum-free 2° cultures.

Cells were generated in serum-free medium in the presence of TGF-β1, as shown in Figure 1. They were resuspended and plated in serum-free 2° cultures (see “Materials and methods”) supplemented with GM-CSF plus TNFα or GM-CSF plus CD40L and cultured for 48 hours. The typical microscopic appearance of cells from these 2° cultures in the presence of GM-CSF plus TNFα or GM-CSF plus CD40L is shown (original magnification, ×40).