Purpose of review: Tissue regeneration requires proper vascularization. In vivo studies identified that the endothelial colony-forming cells (ECFCs), a subtype of endothelial progenitor cells that can be isolated from umbilical cord or peripheral blood, represent a promising cell source for therapeutic neovascularization. ECFCs not only are able to initiate and facilitate neovascularization in diseased tissue but also can, by acting in a paracrine manner, contribute to the creation of favorable conditions for efficient and appropriate differentiation of tissue-resident stem or progenitor cells. This review outlines the progress in the field of in vivo regenerative and tissue engineering studies and surveys why, when, and how ECFCs can be used for tissue regeneration.
Recent findings: Reviewed literature that regard human-derived ECFCs in xenogeneic animal models implicates that ECFCs should be considered as an endothelial cell source of preference for induction of neovascularization. Their neovascularization and regenerative potential is augmented in combination with other types of stem or progenitor cells. Biocompatible scaffolds prevascularized with ECFCs interconnect faster and better with the host vasculature. The physical incorporation of ECFCs in newly formed blood vessels grants prolonged release of trophic factors of interest, which also makes ECFCs an interesting cell source candidate for gene therapy and delivery of bioactive compounds in targeted area.
Summary: ECFCs possess all biological features to be considered as a cell source of preference for tissue engineering and repair of blood supply. Investigation of regenerative potential of ECFCs in autologous settings in large animal models before clinical application is the next step to clearly outline the most efficient strategy for using ECFCs as treatment.