Study of composite vascular scaffold combining with differentiated VSMC- and VEC-like cells in vitro and in vivo

Although research into the tissue engineering of vessels has proceeded at a tremendous pace, many deficiencies still need to be resolved. A well-adopted constructed vessel requires both functional and structural properties to stimulate the native vessel and resist stress and tension in vivo. In the present study, we developed a novel three-layer composite vascular scaffold consisting of differentiated vascular smooth muscle cell-, vascular endothelial cell-like cells, and a rabbit acellular vascular matrix (ACVM)-0.25% HLC-I scaffold. HE staining, immunohistochemical assays, immunofluorescence assays (IFAs), and scanning electron microscopy were performed to monitor the growth status of cells on the scaffold material in vitro. After the vascular endothelial cell -vascular smooth muscle cell-scaffold was implanted into nude mice for three, six, and nine weeks, samples were harvested from the implanted mice and observed visually or by HE staining and IFAs for cell viability and morphology. Additionally, burst pressure resistance experiments were used to assess the maximal pressure that the engineered vessel could resist. We found that the engineered vascular endothelial cell-vascular smooth muscle cell-scaffold vessel possessed favorable biocompatibility and considerable strength, matching native vessels in vivo and in vitro, and may be significant in the future clinical implantation of tissue-engineered vasculature.