Susceptibility of human DC to adenoviral transduction. DC on day 6 of culture were transduced with an adenovirus encoding the marker gene GFP under the same conditions utilized to transduce CCL21-DC. After transduction, DC were cultured up to 48 h. GFP expression was analyzed by flow cytometry at 24 h (A, B) and 48 h culture (C, D), as described in Materials and Methods. A population of GFP+ CD86+ DC at 24 h (B) and 48 h (D) is shown. Staining with isotype control is indicated in A and C. The percentage of GFP+ CD86+ DC is indicated in the upper right corner, and MFI is also reported for D and C. The density plots for one representative experiment of four are shown.