High RPS19 transgene expression increases erythroid colony formation.

Transduction of bone marrow cells from DBA patient 1 using the MND-RIG vector and the MND-GFP control vector. (A) Flow cytometric analysis of transduced CD34⁺ cells. The transduced GFP⁺ and CD34⁺ cells (squared fractions) were sorted by FACSVantage. R1: MND-GFP–transduced CD34⁺/GFP⁺ fraction. R2: MND-RIG–transduced CD34⁺/GFP^low fraction. R3: MND-RIG–transduced CD34⁺/ GFP^highfraction. (B) A quantity of 1000 transduced progenitor cells (GFP⁺ and CD34⁺ cells) were embedded in methylcellulose in the presence of erythropoietin and SCF. CFU-E and BFU-E colonies were scored on day 7 and day 14, respectively. Open bars indicate the number of colonies from MND-RIG–transduced GFP^high cells. Black bars indicate the number of colonies from MND-RIG–transduced GFP^low cells. Gray bars indicate the number of colonies from MND-GFP–transduced GFP⁺ cells. Hatched bars indicate the number of colonies from the mock-transduced, unsorted fraction. One experiment was performed and 3 plates were counted in a blinded fashion. The mean ± SEM are shown.