A team of scientists has used 3D printing to successfully create components of a human heart.
Cardiovascular disease remains a leading cause of illness and death worldwide. Moreover, research has shown that the number of individuals with heart disease is going to increase as the global population ages. It is crucial, therefore, to continually conduct research and identify new ways of preventing and curing cardiac disease. This is particularly important for patients that suffer from end-stage organ failure, who are likely to die if they do not receive a transplant in time.
3D bioprinting has significantly improved our ability to produce biomaterials, including implantable meshes, for the purpose of therapeutic benefit and research. Eventually, researchers hope to use bioprinting technology to successfully print cells, biomaterials, and even entire organs outside of the body. These biomaterials can subsequently be implanted into patients as therapies for various diseases. In recent years, 3D bioprinting has allowed the successful printing of patterned tissues, the creation of blood vessel-like networks, and many other implantable scaffolds. However, the technology has been limited in its ability to print living cells or soft biomaterials, including extracellular matrix proteins found in the heart’s muscle. This network of extracellular matrix proteins provides a scaffold for cardiomyocytes, the contractile cells of the heart, to contract from. 3D printing these proteins, most notably collagen, has been difficult because these soft and dynamic biological materials are hard to support during the printing process. The resulting products often sag and are not suitable for subsequent use.
A team of researchers from Carnegie Mellon University recently developed a newer version of the freeform reversible embedding of suspended hydrogels (FRESH) system to successfully print collagen scaffolds and other soft biomaterials for the purpose of creating different components of the human heart, including blood vessels, heart valves, and the heart’s muscle tissue. The newer technology uses a temporary support gel, which can prevent soft biomaterials from sagging. Furthermore, the researchers developed a new strategy where they rapidly changed the acidity of the surrounding environment to promote collagen protein self-assembly so that it can retain its proper function in the biomaterial.
Beyond creating smaller components of the human heart, the researchers also successfully generated the heart’s muscle using human cardiomyocytes. Assessment of the 3D printed muscle showed that the cells were fully functional and had the electrical properties that they would exhibit in the normal intact heart. While scientists are still a long way from successfully 3D printing whole anatomically accurate and functional organs, the current study is a step in the right direction. The successful printing of collagen scaffolds and other soft biomaterials will be useful in the development of novel implantable meshes for many different organ complications.
Written by Haisam Shah
Reference: Lee, A., Hudson, A. R., Shiwarski, D. J., Tashman, J. W., Hinton, T. J., Yerneni, S., … & Feinberg, A. W. (2019). 3D bioprinting of collagen to rebuild components of the human heart. Science, 365(6452), 482-487.
Image by krzysztof-m from Pixabay