Differential transduction of naive CB and naive adult CD4⁺ T cells by IL-7–displaying lentiviral vectors.

Resting CD4⁺ naive cord blood, as well as quiescent naive and memory adult T cells were transduced with lentiviral vectors (A) following a preactivation of these CD4⁺ T-cell subsets for 3 or 6 days with rIL-7, (B) immediately upon isolation, or (C) upon isolation followed by a second transduction performed 3 days later. Cells were transduced with VSV-G–pseudotyped lentiviral vectors (G), IL-7–displaying VSV-G–pseudotyped lentiviral vectors (G/IL-7SU or G/IL7SUx), and VSV-G–pseudotyped lentiviral vectors in the presence of rIL-7 (G+rIL-7), using MOIs of 20 to 25. Cultures were continued for 3 days (A,C) or 7 days (B) after transduction, and EGFP expression was then monitored by FACS. Means ± SDs for at least 3 independent experiments are shown.