Jun 4, 2018

5 Most Promising 3D Printed Organs for Transplant

3D bioprinting, the process of using bioink composed of tissue or human cells, has come a long way over the last decade. The goal of developing functioning whole organs, such as kidneys, livers or hearts, is becoming more and more of a reality.

What is Bioprinting?

3D bioprinting uses a typical layer-by-layer 3D printing method, depositing bioinks or biomaterials, to create 3D tissues or structures used for medicine or tissue engineering. This technology is being applied to regenerative medicine to address the need for tissues and 3D printed organs for transplant.

While most organs are still in the early stages of development, 3D bioprinting has already demonstrated some success, especially in the area of skin and bone.

The Kidney

Of the potential 3D printed organs for transplant, a 3D printed kidney is one of the most difficult. That’s because of the complexity of the organ’s structure, which is necessary for its function.

In 2016, Jennifer Lewis’ lab at Harvard developed a novel printing method that uses ‘inks’ consisting of kidney cells and surrounding material. This ink ends has the consistency of toothpaste and can be extruded at room temperature, allowing them to make complex tissue structures.

Thanks to this novel ink, the research group has been able to recreate part of the nephron, the functional unit of the kidney. The nephron is responsible for filtering the blood and reabsorbing all of the useful components and excreting out the rest. With this acheivement, the field of 3D printed organs for transplant is a lot closer now to creating a functional kidney.

The Liver

Organovo, a San Diego-based bioprinting company, has already demonstrated that it can 3D print human liver tissue patches, implant them into mice and be functionally beneficial. 

These liver patches are currently as thick as a dollar bill and are used to extend patients’ lives until they can recieve proper transplants. These partial liver transplants are currently targeted for human trials in 2020.

Until liver transplants begin, Organovo is also using their bioprinted liver patches for preclinical testing and drug discovery resereach. Using multi-cellular 3D human tissues that mimic a real liver, they can better assess the effects of certains drugs and compounds without risking lives.

The Heart

The most promising of of 3D printed organs for transplant is the heart. As organs go, the heart is actually one of the easiest to recreate because it doesn’t employ any complex biochemical reactions. Rather, its primary function is to act as a pump.

Biolife4D, a biotech startup, hopes to create miniature hearts for testing in small animals within a year. The process was developed in part by several research groups:

  • First, a patient’s heart is scanned with an MRI machine, creating a digital render of the shape and size.
  • Next, using a blood sample from the patient, blood cells can be converted into stem cells and then converted again into heart cells. The resulting hydrogel mixture is their bioink to be used with a 3D printer.
  • The bio-ink is printed layer by layer onto a biodegradable scaffold. It provides a structure on which cells can grow, forming the exact shape of the patient’s heart.
  • Within a few days, the hearts cells join and begin to beat like a heart. Once ready, the scaffold can be removed with heat and the heart is ready for transplant.

Using the patient’s own cells to prepare the organ means it’s less likely to be rejected by the host. As such, the patient isn’t required to take immune-suppressant drugs, which might otherwise make them susceptible to other diseases.

The Cornea

The cornea is the clear, outermost layer of the eye. It’s essential for helping focus our vision and protecting the eye from the environment.

Millions of people around the world suffer from corneal blindness due to disease or scarring and thus require corneal transplants. As such, the cornea is a strong candidate for 3D printed organs for transplant.

For the first time, Che Connon’s group from Newcastle University have been able to 3D print a human cornea. By combining stem cells with alginate and collagen, they’ve created a unique bioink that can be extruded in circles to form the shape of the cornea in less than 10 minutes.

A huge advantage of this technique is that the cornea can be personalized to the patient. Scanning their eye provides data that can be used to match the shape and size of the new cornea.

It is important to note, though, that this is so far only a proof of concept. Transplants for humans require a lot more work to be done to ensure safety and efficacy.

Bones

In 2017, a team from the University of Glasgow developed a new technique called “nanokicking” to grow 3D samples of mineralized bone for the first time. Using this method, the researchers were able to turn stem cells taken from human donors into 3D bone grafts. These grafts could be reaady for implantation as early 2020.

In the meantime the group has already demonstrated functional bone grafts after implanting them into a dog’s leg — one which would otherwise have required amputation. This technology is also specifically being funded through a collaborative effort with Find A Better Way. The goal is to help those who have suffered landmine related injuries.

License: The text of "5 Most Promising 3D Printed Organs for Transplant" by All3DP is licensed under a Creative Commons Attribution 4.0 International License.

Subscribe to updates from All3DP

You are subscribed to updates from All3DP

You can’t subscribe to updates from All3DP. Learn more…Subscribe

You can’t subscribe to updates from All3DP. Learn more…

B719266D-CB2F-4571-9ABD-AFEC8A7D79DCB719266D-CB2F-4571-9ABD-AFEC8A7D79DCB719266D-CB2F-4571-9ABD-AFEC8A7D79DC