Studio in vitro e in vivo della capacità differenziativa di cellule CD105 positive da cordone ombelicale e da sangue cordonale umano

Stem cells have become worldwide interesting because they can be potentially employed for the treatment of many different types of deseases; moreover, they can be manipulated representing a promising tool for genetic therapy. Mesenchymal stem cells (MSC) can be obtained from several adult tissues and from fetal-derived tissues, such as umbilical cord, umbilical cord blood and placenta, and they can be induced to differentiate into several cell types. Nevertheless, proliferation and differentiation potential of these cells has not yet been explained; particularly differentiative potential of fetal-derived tissue cells remains to be investigated. In this study, umbilical cord blood (UCB) and umbilical cord (UC) have been evaluated as potential sources of MSC. For this purpose, a subpopulation of cells expressing CD105, a membrane antigen well known as marker of MSC, has been isolated from UCB and UC. The proliferative potential and plasticity of CD105-positive cells have been investigated in vitro by means of synthetic or natural supports and/or using differentiative media containing inductive factors. Finally, in view of clinical applications, the engraftment of these cells in a model of chemical-induced liver injury has been verified. Collectively, our data have demonstrated in vitro the plasticity of UCB and UC CD105-positive cells not only towards mesodermal lineage cells (osteogenic and adipogenic lineage) but also towards endodermal lineage cells (hepatogenic lineage). These results suggest that CD105-positive cells could be usefully employed in regenerative medicine. In fact, due to availability, safety in the collection and lack of ethical issues, UCB and UC may become elective sources of multipotent MSC.