|Artificial blood vessels are created using hydrogel constructs.--Courtesy of Khademhosseini Lab|
Researchers at Boston's Brigham and Women's Hospital used a 3-D bioprinting method to create functional synthetic blood vessels that could someday be used for developing transplanted tissues and testing drugs outside of the body.
The team 3-D printed a mold of the blood vessels, comprising naturally occurring agarose fiber, and then covered it with hydrogel, a jelly-like substance. They were able to create vessels by removing the mold from its hydrogrel cast--without harming the surrounding cells.
"What is unique about our approach is that the fiber templates we printed are strong enough that we can physically remove them to make the channels," said researcher and biomedical engineer Ali Khademhosseini in a May 30 statement. "This prevents having to dissolve these template layers, which may not be so good for the cells that are entrapped in the surrounding gel."
The researchers said the synthetic vascular network improved the surrounding cells' transportation systems, viability and differentiation. The team was able to get the vessels to exhibit an endothelial monolayer, the lining of cells that forms the interior of blood vessels, demonstrating the network's sophistication.
Synthetically created transplants are a long way away, but the utilization of such artificial biological systems for drug development research is a realistic intermediary until then. Companies such as Organovo are already active in this arena, and tout the method's cost savings compared to animal studies, which don't always provide accurate information about human interactions. Organovo is focusing on liver cells for toxicity testing for now, but the technology developed by researchers at Brigham and Women's Hospital could be applied to tissues for any part of the body.
"Engineers have made incredible strides in making complex artificial tissues such as those of the heart, liver and lungs," Khademhosseini said in the statement. "However, creating artificial blood vessels remains a critical challenge in tissue engineering. We've attempted to address this challenge by offering a unique strategy for vascularization of hydrogel constructs that combine advances in 3D bioprinting technology and biomaterials."
The research is described in greater detail in the journal Lab on a Chip.
- read the release
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