What makes blood pump: Encouraging vascularization in bioprinting

Combining 3D printing techniques with cells to create biological tissue seems like something from science fiction, but the technology is already mature enough to synthesize tissue for research. Despite the promise of the technique, achieving vascularization — getting the blood to move through the vessels — is currently a bottleneck to improving bioprinting.

Jiao et al. evaluated the current state of vascularization in bioprinting in a review, analyzing the biggest challenges facing the field.

“I was struck by the gap between structural achievement and functional evaluation,” said author Tian Jiao. “Many studies successfully print anatomically similar vessel structures — with good printing fidelity, uniform pores, and certain mechanical strength — yet far fewer systematically evaluate long-term functional behaviors.”

While researchers are very adept at printing tissues accurately, making them function properly, which is important for using the tissues for biomedical research, remains an issue.

The authors categorized the main challenges to vascularization with current bioprinting methods, spanning materials and standardization. In general, there is still a tradeoff between printability and biological activity, and like most scientific instruments, high-precision printers are expensive. Working with living cells also comes with its own difficulties, from keeping them alive to getting the consistency of the cell-based ink right.

Jiao hopes this review will persuade researchers to go beyond printing for structural accuracy and encourage them to design “functionally mature vascular constructs.”

“I also hope it inspires cross-disciplinary collaboration between materials science, biotechnology, and clinical medicine and encourages the community to establish standardized translational evaluation systems so that functional vascular bioprinting can move from laboratory research to clinical routine application,” Jiao said.

Source: “From structural mimicry to functional maturation: Advances in functional vascular 3D bioprinting,” by Tian Jiao, Chaofan Sun, Congzheng Zhang, and Liang Li, Biointerphases (2026). The article can be accessed at https://doi.org/10.1116/6.0005743 .