In vitro differentiation of porcine Aortic Vascular Precursor Cells to Endothelial and Vascular Smooth Muscle cells.

Recent findings suggest that progenitor and multipotent mesenchymal stromal cells (MSCs) are associated to vascular niches. Cells displaying mesenchymal proprieties and differentiate to whole components of a functional blood vessel, including endothelial and smooth muscle cells, can be defined Vascular Stem Cells (VSCs). Recently, we isolated a population of porcine Aortic Vascular Precursor Cells (pAVPCs) which own MSCs and pericyte-like proprieties. The aim of the present work was to investigate whether pAVPCs possess VSC-like properties assessing their differentiation potential toward endothelial and smooth muscle lineages. pAVPCs, maintained in a specific Pericyte Growth Medium (PGM), were cultured in high glucose DMEM + 10% FBS (LTM) or in human Endothelial Serum Free Medium + 5% FBS and 50 ng/mL of hVEGF (EDM). After 21 days of culture in LTM, pAVPCs showed an elongated fibroblast-like morphology and it seems to organize in cord-like structures. qPCR analysis of smooth muscle markers (αSMA, CNN1, SMM-hc) showed a significant increment of the transcripts and immunofluorescence analysis confirmed the presence of αSMA and SMM proteins. After 21 days of culture in EDM, pAVPCs displayed an endothelial cell-like morphology and revealed the up-regulation of the expression of endothelial markers (CD31, VE-Cadherin, vWF, eNOS) showing the CD31 typical pattern. In conclusion, pAVPCs could be defined a VSC-like population considering that, if maintained in a specific pericytes medium, they express MSCs markers and they have, in addition to the classical mesenchymal trilineage differentiation potential, the capacity to differentiate in vitro toward the smooth muscle and the endothelial cells phenotypes.