Scientists in Boston have created the first synthetic blood vessels using 3D bioprinting techniques. Although successfully created in a lab, we are probably years away from being able to transplant these 3D-printed blood vessels into human organs and tissue.

In a study published last month in Lab on a Chip, a team of researchers from Boston explained how they were able to use a fiber template from a naturally derived sugar based molecule called agarose to create a mold. This mold was then enclosed in a gelatin-like substance called hydrogel to create the synthetic blood vessels. The blood vessels were used to create micro channel networks, which were then embedded into various types of gels and eventually made into larger organs. "Engineers have made incredible strides in making complex artificial tissues such as those of the heart, liver and lungs,” Ali Khademhosseini, lead researcher on the project, explained to the International Business Times.

Although the creation of synthetic blood vessels was groundbreaking, the most impressive aspect of the project was the team’s success in recreating endothelial cells, RT reported. Due to the extremely delicate nature of blood vessels, getting the synthetic vessels' makeup just right was a difficult procedure. The inner walls of blood vessels are lined with endothelium, which is created from endothelial cells. These endothelial cells perform the main functions of the blood vessels: filtering fluids, trafficking hormones, hemostatis, and more.

RT explains that without this essential layer the synthetic blood vessels would be useless. Khademhosseini and his team were able to successfully create the endothelial cells in the synthetic blood vessels. “The fiber templates we printed are strong enough that we can physically remove them to make the channels," Khademhosseini explained. It was in these channels that the endothelial monolayers were grown.

Blood vessels work by transporting nutrients and oxygen to tissues and prevent cells from dying, IBT reported. Although the synthetic blood vessels have been created, Voice of Russia explains how science is most likely still years away from being able to 3D-print real, living blood vessels that can be transplanted into a human being’s organs and tissues. Researchers are still optimistic that this goal will eventually be reached.

“In the future, 3D printing technology may be used to develop transplantable tissues customized to each patient's needs or be used outside the body to develop drugs that are safe and effective,” Khademhosseini told IBT.

 

Source: Khademhosseini A, Bertassoni LE, Cecconi M, et al. Hydrogel bioprinted micochannel networks for vascularization of tissue engineering constructs. Lab on a Chip. 2014.