γc expression and γc-dependent cytokine signaling in ED-7R cells following lentiviral vector transduction. (A) ED-7R cells were transduced at an MOI of 25 by vectors encoding γc under the transcriptional control of the indicated promoters. After 10 days cells were labeled with anti-γc antibody and analyzed by FACS. (B) Immunofluorescence images of the above transduced cell populations labeled with anti-pSTAT5 antibody in the absence (column 1) or presence of IL-2, IL-7, or IL-15 (columns 2, 3 and 4, respectively). Scale bar represents 50 μm.