[Artificial endothelial cell. From stem cells to transdifferentiated endothelial cells]

Construction of efficient substitutes of human tissues is strongly dependent on the availability of an adequate source of viable and functional cells. In this work, we have analyzed the transdifferentiation capabilities of Human Wharton's jelly stem cells (HWJSC) into transdifferentiated endothelial-like cells (Tr-ELC) in order to establish the potential usefulness of these cells in vascular tissue engineering. Our results show that artificial endothelial cells became more polygonal and less proliferative than Wharton stem cells. In addition, the marker of mesenchymal undifferentiation CD9 is downregulated in artificial endothelial cells, suggesting that these cells can be in the process of adult differentiation. Besides, microarray analyses revealed that some genes with a role in defining the endothelial phenotype and structure are upregulated (CDH5, ICAM2 and PECAM1), although a number of genes related to relevant endothelial cell functions (CD36, ECE2, VWF, THBD, PGI2, and ACE) did not change or were only partially induced. All this implies that Wharton stem cells are able to efficiently transdifferentiate into artificial endothelial cells at the phenotypical level following a hierarchical pattern of gene activation, with an earlier induction of morphological and phenotypical genes.