Bioactive vascular buds promote collateral vessel formation by grafting on the artificial vessel walls.

Vascular injury and some chronic ischemic lesions usually lead to insufficient blood supply to tissues, which will lead to tissue ischemia or even necrosis in severe cases. Current artificial blood vessels lack effective collateral vascularization capabilities to provide adequate blood supply in areas with restricted blood flow. Herein, inspired by the grafting of tree buds to form lateral branches, the vascular buds model was successfully constructed by inoculating HUVECs into bioactive hydrogel microspheres. Under the influence of ions dissolved from bioactive glass and three-dimensional culture environment, the cytoskeleton was remodeled, the cells showed obvious outward migration and budding trend, which significantly enhanced the angiogenesis ability. After grafted vascular buds to the lateral wall of the artificial blood vessel, a large number of collateral vessels are formed, which effectively alleviates the tissue ischemia in the region through which blood vessels pass. This study confirms the impact of bioactive ions on angiogenesis in a three-dimensional environment and offers novel insights for the development of lateral branches in artificial blood vessels.