Comparison of vectors with or without integrase.

B cells were transduced with HIV-CMV vectors or HIV-EF1α vectors, and the vectors were packaged either with integrase mutant (integrase −) or wild-type (integrase +) plasmids. Vector amounts were normalized using reverse transcriptase activities, and they corresponded to an MOI of 10. Two independent experiments; same protocol for culture and cell analysis as in Figure 1; transductions on day 4 (HIV-CMV) or day 5 (HIV–EF1-α). Percentages of GFP⁺ cells among gated CD19⁺7-AAD^low cells are indicated.