Efficient transduction of patients’ CD34⁺ cells using the ADA2-LV. (A) Number and percentage of myeloid (CFU-GM), erythroid (BFU-E), and mixed (CFU-GEMM) colonies derived from CD34+ cells from 2 patients and 2 HDs left untreated (UT) or transduced with LV-ADA2 or LV-GFP at an MOI of 10 and 50. (B) Transduction efficiency was calculated as the proportion of vector-positive colonies. (C) Average VCN per genome was evaluated on positive colonies by droplet digital polymerase chain reaction. *P < .05, **P < .01, ***P < .001. PT, patient.