The TRIP vector efficiently transduces NOD/SCID mice long-term reconstituting human cells.

(A) Phenotype of cells harvested from the BM of NOD/SCID mice grafted 15 weeks earlier with 7 × 10⁴CD34⁺ CB cells transduced with the TRIP vector. At that time, human CD34⁺ cells were isolated by immunomagnetic selection. CD34⁺CD38⁻ primitive cells were further sorted on a FACS Vantage. (B) Phenotype of cells differentiated from 10⁴ CD34⁺CD38⁻ cells, purified from reconstituted mice, following bulk culture in lymphomyeloid conditions. rhEPO was added to the bulk culture to allow terminal erythroid differentiation (glycophorin A [GPA⁺] cells). (C) The experiment was performed as described in panel B, except that the cells were cultured at 1 cell per well in the absence of rhEPO. Progeny of 39 of 120 cultures proliferated sufficiently to be phenotyped by FACS and were assessed 2 to 3 weeks later using flow cytometry, as illustrated in Figure 4B. Eight of 39 (20%) clones produced CD19⁺ B, CD56⁺ NK, and CD11b⁺ myeloid cells defining multipotential progenitors. Shown in panel C is a representative analysis of the progeny of an input multipotent progenitor.