When we talk about printing, what comes to mind? 2D printing to print out pictures and words on paper? 3D printing to create amazing 3D objects out of plastic or even metal? Or laser printing to etch images and words on wood? How about bioprinting?
Bioprinting is a new form of 3D printing that uses living cells to print synthetic tissues and organs that can be used as implants to replace damaged tissue or organs in the human body.
Growing living cells and tissues is not a new technology and has been done for many years by scientists, who cultivate the cells and tissues in a petri dish. However, making an entire 3D organ, bone, or blood vessel in a simple, cost and time effective way is the technology of the future.
How Does Bioprinting Work?
While a regular 3D printer uses materials like plastic, metal, or ceramic to print, a bioprinter uses biomaterial referred to as “bio-ink,” which is just a cultivation of specific cells from a certain organ or tissue that needs to be printed.
The bioprinter prints layers upon layers of biomaterial, which includes living cells, in order to 3D print structures like skin tissue, blood vessels, and organs. Other times, adult stem cells are used for the printing since they can also develop and form the cells required for the tissue that needs to be printed. Most times a scaffold, or foundation, is printed first with the biomaterial on top so the structure of the cell or tissue is created and stabilized. Other times the cell can take on its shape by itself.
The History Behind Bioprinting
1999: Scientists realized that stereolithography (the original name for 3D printing) technology could be used for clinical purposes. They 3D printed a synthetic structure of the human bladder which they then covered in cells taken from patients and eventually grew functioning organs. This was a major milestone in bioprinting.
2002: The 1999 experiment did not physically print living cells or tissue. Instead, it printed a synthetic supporting structure which the scientists used to layer on cells and grow functioning organs. In 2002, scientists were able to use the printer to print out cells and tissue into a working kidney. This organ was able to produce urine and filter blood in an animal model.
2010: A company called Organovo was the first company that was able to bioprint a blood vessel. Since blood vessels are extremely complicated to print, this success was a huge breakthrough. It eventually led to the development of working skin grafts and tiny organs.
Different Bioprints Used Today
Bone grafts: Current bone grafts don’t allow for the creation of new tissue in the area of the graft. However, using bioprinting, scientists have created a matrix of the bone that when implanted in the patient, eventually fuses with the bone over the course of a few months and is even replaced by the patient’s natural bones, encouraging the growth of natural tissue and ensuring mechanical integrity. Scientists hope that as bioprinting gets more complex, we can eventually create reliable bones for complex spinal reconstruction.
Skin grafts: This is also a big area for bioprinting. For burn victims and other people whose skin has been badly damaged by an accident or attack, healthy skin is grafted from another area from the body. Unfortunately, most times there isn’t enough healthy skin to use. The Wake Forest School of Medicine is home to the researchers who successfully used bioprinting to print skin cells directly on a burn wound. Additionally, this form of healing the wounds only requires a piece of skin one-tenth the size of the wound in order to cultivate the right type and amount of skin cells. Of course, this technology is still experimental, and there’s many more aspects of skin that must be taken into account to print anatomically accurate and functioning skin, such as nerves and blood vessels.
Prosthetic Ears: Scientists from the Swiss Federal Laboratories for Materials Science and Technology were able to mix cellulose – a non-toxic and strong material – with hydrogels. According to labiotech.eu, “Hydrogels are great mediums for cell proliferation and growth.” Since hydrogels mostly consist of water, they are combined with cellulose to create a substance that is durable but has the right mechanical properties. After creating the ear, which is a part of the body entirely made of cartilage, the scientists realized that they can now use this process to eventually create “cartilage implants in knee joints for patients with arthritis” (labiotech.eu).
The Challenges of Bioprinting
Even though bioprinting is revolutionary, there are still many unanswered questions related to ethics, pricing of the implants, and liability issues if the implant or transplant fails. Hopefully, as time goes on and technology improves, bioprinting will lead to future innovations and medical breakthroughs.
So there you have it! The world of implants, grafts, and transplants has and will be forever revolutionized by bioprinting. Thanks for reading and stay tuned for more articles!