Differentiation of side population cells isolated from human amniotic mesenchymal cells into vascular endothelial cells

Abstract

Human amniotic mesenchymal side polulation (SP) cells have pluripotency and weak immunogenicity. We attempted to clarify appropriate condition on differentiation of the SP cells into vascular endothelial lineage and to construct tubular formation. The human amniotic mesenchymal cells were isolated from the enzyme-treated amniotic membrane procured from caesarean section and stained with Hoechst33342. SP cells were negatively selected by sorting with fluorescence-activated cell sorting. The expression levels of vascular endothelial markers were evaluated by real-time PCR and immunostaining. The expression levels of HLA class I and class II genes were evaluated by using microarray. Vascular endothelial markers like vWF and KDR in SP cells were more strongly induced by vascular endothelial growth factor (VEGF) in hypoxia for 2 weeks, but long-term induction under hypoxia was not effective for amniotic mesenchymal SP cells to differentiate into vascular endothelial cells. Besides, human amniotic mesenchymal SP cells constructed tubular formation on the MatrigelTM, indicating that the cells had angiogenic potential.