Efficient adipocyte and osteoblast differentiation from mouse induced pluripotent stem cells by adenoviral...

Induced pluripotent stem (iPS) cells, which are generated from somatic cells by transducing four genes, are expected to have broad application to regenerative medicine. Although establishment of an efficient gene transfer system for iPS cells is considered to be essential for differentiating them into functional cells, the detailed transduction characteristics of iPS cells have not been examined. Previously, by using an adenovirus (Ad) vector containing the elongation factor-1alpha (EF-1alpha) and the cytomegalovirus enhancer/beta-actin (CA) promoters, we developed an efficient transduction system for mouse embryonic stem (ES) cells and their aggregate form, embryoid bodies (EBs). In this study, we applied our transduction system to mouse iPS cells and investigated whether efficient differentiation could be achieved by Ad vector-mediated transduction of a functional gene. As in the case of ES cells, the Ad vector containing EF-1alpha and the CA promoter could efficiently transduce transgenes into mouse iPS cells. At 3,000 vector particles/cell, 80%-90% of iPS cells expressed transgenes by treatment with an Ad vector containing the CA promoter, without a decrease in pluripotency or viability. We also found that the CA promoter had potent transduction ability in iPS cell-derived EBs. Moreover, exogenous expression of a PPARgamma gene or a Runx2 gene into mouse iPS cells by an optimized Ad vector enhanced adipocyte or osteoblast differentiation, respectively. These results suggest that Ad vector-mediated transient transduction is sufficient to increase cellular differentiation and that our transduction methods would be useful for therapeutic applications based on iPS cells.