evaluating the expression of self-renewal genes in human endothelial progenitor cells

objective: endothelial progenitor cells (epcs) have a potential application for cell therapy, however, their biological nature is not well-understood. epcs also possess some stemness features, such as their clonogenicity and differentiation capacity. the main aim of this study was to evaluate the expression of certain transcription factors regulating self-renewal property of stem cells. materials and methods: in this experimental study, peripheral blood mononuclear cells were isolated from fresh human blood of several volunteers and were cultured in fibronectin-coated plates. epcs were identified based on their morphology and growth characteristic. then, the expression of some markers implicated in self-renewal capacity was assessed in the isolated cells using reverse transcription-polymerase chain reaction (rt-pcr) and immunocytochemistry. results: expression of the cell surface markers, cd31 and cd34, was determined by rt-pcr and immunocytochemistry. furthermore, these cells had the ability for di-ac-ldl incorporation as well as attachment to lectin i. epcs did not express the main stem cell markers, like oct4-a, nanog, and sox2; nevertheless, they expressed the weaker pluripotent markers, including oct4b and oct4-b1 spliced variants, such as nucleostemin and zfx. furthermore, the expression of nucleostemin and zfx genes revealed a decreasing pattern from days 4th to 11th. conclusion: the main regulators of stem cell self-renewal genes, including oct4-a, nanog, and sox2 are not expressed in epcs. forced expression of these genes can elevate the stemness property and clinical application of epcs.