Vascularization of engineered bone tissue is critical for ensuring its survival after implantation and it is the primary factor limiting its clinical use.A promising approach is to prevascularize bone grafts in vitro using endothelial progenitor cells (EPC) derived from peripheral blood.Typically, EPC are added together with mesenchymal stem cells (MSC) that differentiate into osteoblasts.One problem with this approach is how to promote traditional tissue engineering bone survival with a minimally invasive method.In this study, we examined the effectiveness of administering to stimulate the release of peripheral blood stem cells and their co-culturing system for generating prevascularized engineered bone.