How do you repair a damaged heart? With love? Gifts of candy and flowers? Romantic actions? Well, no. A good way to repair a damaged heart is to patch it. Scientists from the University of New South Wales now demonstrated that you can patch the heart with a 3D printer, dry ice, a silicon mould and a copper plate. However, the key ingredient is frozen silk.
A perfect patch for a broken heart would not only cover the damage, but also promote healing. Australian scientists have just developed a patch, made from a material to which healthy heart stem cells attach themselves and grow. And that material is silk. It serves as a form of scaffolding that trains isolated heart stem cells to grow in a way that mimics the native tissue. Of course, for that to work at all, cells have to arrange themselves to form an orderly fabric. And that is the big challenge that scientists picked up.
Growing functional cardiac tissues in a laboratory setting would be a huge leap forward in surgical treatment of damaged hearts. And now scientists are moving closer to it. They 3D printed a silicone mold, where water and silk solution is poured in. Then the mold is placed on a copper plate, cooled by dry ice. This made water freeze from the bottom up, which left silk perfectly arranged as a bunch of straws. When water (ice) was removed through freeze-drying process, this structure was ready to be used as scaffolding for heart stem cells to grow on.
This explanation might have sounded rather simple, but the process itself requires a tremendous amount of precision. Solution, timing and temperature have to be controlled very accurately for this to work. Dr Jelena Rnjak-Kovacina, one of the authors of the study, said: “If you change the ice structure, you change the pore morphology of the silk structure left behind. To change the ice structure, you just mess with how quickly you’re freezing it, the amount of silk you use or the type of silk to use as each form freezes differently, resulting in a different pore morphology”.
Although complicated, this process is actually showing a huge potential. It can be used to produce various tissues quite cheaply, compared to other methods. No specialized equipment is actually needed and the results are easily replicable in other laboratories around the world. Scientists hope that this is exactly what is going to happen – many researchers will contribute to this development.
In the future this method could be used to develop all sorts of tissues, not just the heart one. Results are very positive and easily accessible. Still, a bit more research is needed to perfect this technique.