Correction of the MMC hypersensitivity of hematopoietic progenitors from FA-A patients using a short transduction protocol with a therapeutic lentiviral vector. (A) Bone marrow CD34⁺ cells from 3 FA-A patients were prestimulated for 8 to 10 hours and then transduced for another 12 to 14 hours with a nontherapeutic (PGK-EGFP.Wpre*; red bars) or a therapeutic (PGK-FANCA.Wpre*; blue bars) lentiviral vector. Transduced samples were then grown in methyl-cellulose, in the absence or the presence of 10 nM MMC, to test their sensitivity to MMC. (B) Similar experiments were conducted using G-CSF plus plerixafor-mobilized PB CD34⁺ cells from FA-A patients. (C) Correlation analysis between the proportion of colonies resistant to 10 nM MMC and the mean VCN/colony in pooled colonies grown in the absence of MMC. (A-B) CD34⁺ cells were transduced with pre-GMP and GMP lots of the therapeutic vector, respectively.