One of the biggest challenges in healing large or complex bone injuries is the lack of blood vessels in the implanted scaffold.

While 3D bioprinting has made it possible to design bone-like structures using biocompatible  materials and bone-forming cells, these constructs often fail because they can’t support proper nutrient flow.

Without a built-in vascular system, cells inside the printed scaffold die, slowing or even  stopping the healing process. Current solutions mostly focus on bone regeneration but ignore the equally important need for blood vessel formation. To truly mimic natural bone healing, we need a strategy that supports both bone and blood vessel growth.

The key lies in combining osteoblasts (bone-forming cells) and endothelial cells (blood vessel forming cells) in a way that they work together inside the same printed structure. Solving this issue could bring us much closer to creating fully functional, implantable bone grafts.

This project aims to build a 3D bioprinted bone scaffold that includes both bone-forming and  blood vessel-forming cells, making it more lifelike and functional. The idea is to use a dual bioink printing system. One bioink will contain osteoblasts mixed with Silk Fibroin + Laponite and nano-hydroxyapatite—materials that encourage bone growth. The other will carry endothelial cells within a soft, natural hydrogel like collagen or fibrin, which supports the formation of blood vessels.

Using a dual-extrusion 3D printer, both bioinks will be deposited in a controlled pattern to form  a living, layered structure where cells can grow and interact. After printing, the scaffold will be crosslinked and placed in a nutrient-rich environment that helps both cell types thrive. Over time, we expect the osteoblasts to form bone tissue while the endothelial cells form capillary like networks. These vascularized constructs will be tested using live cell imaging, staining techniques, and gene analysis.