The ancient Japanese art of origami is useful for making more than just pretty paper cranes and owls. In the future, the practice may be used to produce new human organs--an alternative to the 3-D printed organs that scientists are working on today.
Carol Livermore, a professor of mechanical and industrial engineering at Northeastern University, has long studied microfabrication techniques, like the MEMS systems used to make computer chips. But fabricating human organs has proved to be particularly challenging.
"Part of my research has included assembling individual objects that move independently, like cells, into positions on 2-D surfaces," Livermore explains. Getting those cells from a flat surface into a 3-D surface isn't easy, however. "Sometimes the best ideas come out of moments of profound frustration," she laughs. "How do you turn a 2-D structure into a 3-D structure? The first thing I thought was a cinnamon roll--you roll it up, you can fold it."
So Livermore, along with a group of scientists and artists (Robert Lang, a prominent origami artist; Roger Alperin, an origami mathematician; Sangeeta Bhatia, an MIT professor who specializes in tissue engineering; and Martin Culpepper, a precision mechanics professor at MIT), set out on a mission to figure out how to turn a cluster of 2-D cells into a functional liver. The research is in the very early stages--Livermore and her team aren't yet working with real cells--but there are already hurdles.
One issue: Biological work has to be done in a clean environment, but when you make origami, you fold paper and press down creases with your fingers. "We can't do that to make tissues because we need it to stay appropriately clean so we don't contaminate it," says Livermore. "We will wind up touching it at some level, but we want to minimize touch, and there are things that could happen via sterile probes held by humans or machines."
Design tricks are one way to decrease touch. The Miura Fold, a famous origami pattern of creases that forms a folded block when you grab opposite corners of paper and push them together, is an example of the kind of "single degree of freedom fold" (where you touch an object in just two places and the whole thing folds up in a pattern) that the team is looking at.
Another challenge is taking the 3-D design of a real tissue and translating that into origami instructions. "If we need blood to flow here, here and here, and these kinds of cells in these places, what's the right way to design a folded structure so that it imitates the kind of final tissue architecture that you need?" she asks. Precision is a big factor in making the designs work--a poorly aligned section of blood vessel could compromise the whole organ.
Livermore mentions 3-D printing as one of the promising alternative techniques. But researchers still need to figure out how to print organs without harming them from the forces applied during the printing process. That's just one of many challenges that will keep 3-D printed organs from the mainstream for decades to come.
In the immediate future, Livermore and her team have a number of goals, including figuring out the origami layouts and necessary mathematics, a first pass design of what a folded structure for liver tissue would like look like, and examining how to use microfabrication to get creases to fold the right way. By year two, the team hopes to start experimenting with real cells. But a real origami organ? That's probably not much closer to reality than a usable 3-D printed organ. One can hope.