FLK1+ progenitor cells derived from mouse induced pluripotent stem (iPS) cells for cardiovascular repair

Induced pluripotent stem (iPS) cells are a novel source of stem cells obtained from mammalian somatic cells by repro-gramming the genome to a pluripotent state. These iPS cells are almost indistinguishable from embryonic stem cells and offer the possibility to generate autologous patient-specific pluripotent stem cells. The aim of the present study was to characterize the potential of murine iPS cell-derived FLK1+ progenitor cells to give rise to cardiovascular cell types in vitro and in vivo. FLK1 + progenitor cells were FACS-sorted from differentiating murine iPS cells and either reaggregated and further cultivated on gelatin-coated dishes or injected into the acute ischemic hearts of LAD-ligated SCID-beige mice. Cultivated murine iPS cell-derived FLK1 + progenitor cells gave rise to self-beating cardiac troponin T expressing cardiomyocytes, alpha -smooth muscle actin positive cells and CD31 expressing endothelial cells. Using an iPS cell clone ubiquitously expressing the YFP variant, Venus, in the nucleus we were able to detect cell derivatives of transplanted FLK1 + progenitor cells in infarcted myocardium of SCID-beige mice. The characterization of these cell derivatives and possible effects on cardiac function is currently under investigation. In conclusion, iPS cell-derived FLK1 + progenitor cells are able to differentiate into cells of cardiovascular lineages. This source of cells might therefore be used for cardiovascular regeneration approaches.