The opportunities enabled by 3D printing within design and construction are significant, but the possibilities generated within medicine are truly astounding. Bioengineers now routinely make complex living tissues via additive manufacturing, with the goal to create entire replacement organs for human patients—or to grow living meat for consumption without requiring the bodies of animals. One challenge remains, though, in the printing of vascular networks, which have proven too delicate to construct in a layer-by-layer fashion.
Inspired after viewing the "Body Worlds" exhibit, in which he viewed isolated polymer casts of human vasculature, University of Pennsylvania postdoctoral fellow Jordan Miller thought of the idea to print freestanding vascular networks separately from other tissues. Miller and his research team developed a particular formulation of sugar to be used to create a model of a vascular network, later adding cells to this independent three-dimensional lattice. As in lost-wax casting, the sugar vasculature is readily dissolved when desired, leaving a more accurate and reliable circulatory system behind.
“This new platform technology, from the cell’s perspective, makes tissue formation a gentle and quick journey,” said Penn scientist Christopher Chen, “because cells are only exposed to a few minutes of manual pipetting and a single step of being poured into the molds before getting nourished by our vascular network.”
The Penn researchers developed their new technique using RepRap and Makerbot technology—the same open-source tools used by many designers and DIY-enthusiasts. “We want to redesign the printer from scratch and focus it entirely on cell biology, tissue engineering and regenerative medicine applications,” Miller said.