In a study published in the latest issue of Cell Reports Medicine, scientists from the National Primate Research Center in Wisconsin and the University of Wisconsin Madison demonstrated a "universal life pipeline" - a novel small-diameter vascular graft developed using stem cell-derived arterial endothelial cells (AECs). This achievement is of great significance for advancing research in biotechnology and vascular surgery.

Blood vessels are known as the "life vessels" of the human body. Currently, synthetic vascular grafts have been widely used for repairing large blood vessels, but for small diameter vessels such as those used in coronary artery bypass surgery, the existing options are very limited. The usual method is to extract blood vessels from other parts of the patient's body, but this is not only highly invasive, but also limited by the number and quality of available blood vessels, especially when the patient has comorbidities. Another method is to use blood vessels from the donor, but this approach can easily trigger immune rejection reactions.

To address these issues, scientists employed a small graft made of ePTFE material and treated its surface with a dual layer coating of dopamine and fibronectin, allowing stem cell-derived AECs to adhere to the interior of the ePTFE graft. These cells have self-renewal ability and can differentiate into any type of human cell, providing an infinite source of cells.

Scientists implanted this bioengineered graft into the femoral artery of rhesus monkeys. The rhesus monkey is a non-human primate model commonly used to simulate human biological responses. The study compared three different types of grafts: bare ePTFE grafts, grafts lined with expression compatibility complex (MHC) AEC, and grafts lined with MHC deficient (double knockout) AEC. The results showed that transplants containing wild-type AEC exhibited the best functional persistence and showed no signs of failure such as stenosis or thrombosis within 6 months. In addition, the endothelial cells of the transplant are refilled by host cells, which helps to maintain long-term stability.

The next step for this achievement may be to conduct human clinical trials, and the characteristic that this transplant can differentiate into any human cell type is very important for human vascular bypass surgery.