3-D Bioprinting Sector

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>>> 3D Bioprinting: Eradicating Transplantation Waiting Lists And Testing Drugs On Living Tissues


The Medical Futurist

11 March 2021


https://medicalfuturist.com/3d-bioprinting-overview/


From time to time, news arises about 3D-printed organs. On such occasions, people usually think that a machine can already create readily available, implantable human organs. However, the reality is far from this optimistic image.

Researchers worldwide are working on possible solutions: from a group that printed a miniature kidney, through technological solutions like BioAssemblyBot we wrote about earlier, to entirely new methods that can lead to patient-specific heart tissue printing. The list is long and set in a clinical setting. We checked out where the technology stands today and where it might lead us in healthcare tomorrow.

3D bioprinting can be the response to worldwide organ shortages and the increasing reluctance to test new cosmetic, chemical, and pharmaceutical products on animals. Whether it will become a reality anytime soon is not certain, although research efforts have grown rapidly over the past years. As seen in this video, the technology behind bioprinting is getting better and (much) faster. However, this hydrogen-based technology is still not bioprinting – it is not the content but the printing technology itself. However, a breakthrough might be just around the corner.

Here’s how bioprinting will break into healthcare revolutionising organ donations and animal testing.

What is bioprinting?

Put the term bioprinting next to Earth-invader androids, shiny spaceships in a post-apocalyptic setting, and you’ll get the next Hollywood blockbuster. However, as opposed to malevolent aliens, bioprinting not only exists in sci-fi movies, but it will also transform healthcare in the following decades. Before going into details, though, let’s dissect the technology itself.

Three-dimensional (3D) bioprinting is a state-of-the-art technology that means creating living tissues, such as blood vessels, bones, heart or skin, via the additive manufacturing technology of 3D printing. Traditional 3D printing implies the production of three-dimensional solid objects from a digital file, using a layering process. In its most common version, a source material, such as plastic, is liquefied, and then the machine adds layer after layer on the platform until you have a fully formed object.

Needless to say, printing organs is a “little bit” more complicated. In the early 2000s researchers discovered that living cells could be sprayed through the nozzles of inkjet printers without damaging them. However, it is not enough to have the cells themselves, they need a nurturing environment to stay alive: food, water, and oxygen. Nowadays, these conditions are provided by a microgel – think of gelatin enriched with vitamins, proteins, and other life-sustaining compounds. Moreover, to create conditions fostering the fastest and most efficient cell growth, researchers plant the cells around 3D scaffolds made of biodegradable polymers or collagen so they can grow into fully functional tissue.

How to 3D print an organ

Let’s take the example of the bladder, a simpler organ consisting of only two types of cells. At first, researchers scan the patient’s organ to determine personalised size and shape. Then they create a scaffold to give cells something to grow on in three dimensions and add cells from the patient to this scaffold. That’s painstakingly labour-intensive work and could take as long as eight weeks. Finally, a bioreactor creates the optimal environment for the cells to grow into an organ. When doctors finally place the organ in the patient, the scaffold has already disappeared or disappears soon after surgery.

This description cannot demonstrate how difficult and time-consuming the entire process is. We are a long way, even decades away, from bioprinting fully functioning, complex organs; however, 3D bioprinting is already used to generate model tissues for research and is also used in regenerative medicine.

A solution for organ shortages

The solution to alarming worldwide organ shortages comes from technology. 3D bioprinting is the response of technology to critical tissue shortages hampering medical professionals’ tasks and endangering many lives. In the U.S., a new person is added to the waiting list of organ donors every 9 minutes. The number of patients waiting for an organ donor has multiplied five-fold in the last 26 years. 17 people die every day due to the lack of available organs in the U.S. alone.

Other countries are not better off either. In 2018, over 150 000 patients in Europe were registered on organ waiting lists. In the U.K., 408 patients died while waiting for an organ in 2019. In 2020, the U.K.’s organ donation policy changed to an opt-in system, meaning every adult agrees to become an organ donor when they die unless they state that they do not wish to donate. This has remarkably decreased the waiting lines in the country.

Closing the gaps

A team of researchers at Carnegie Mellon University have created a 3D bioprinting technique called “Freeform Reversible Embedding of Suspended Hydrogels” (FRESH). During a panel discussion on the virtual AMS Summit in March 2021, the project’s team leader, Professor Adam Feinberg, noted that “we could have a bioprinted heart in an animal in 12 years.” Talking further about the possible future timeline for the technology, another expert, Katie Weimer, VP of Regenerative Medicine at 3D Systems, said the issue is merely “an engineering problem.”

In a recent interview for our Patreon site, Erik Gatenholm, CEO of CELLINK, estimated the same. He said, “we will see fully functioning organs within the next decade or so.” Gatenholm added, “scientists have been able to bioprint hearts, lungs, kidneys, skin, corneas and more throughout the last 5 years and are currently working towards developing full functioning organs. As of now, the industry is progressing at a steady pace due to the democratisation of 3D bioprinting technology.”

Bioprinting making waves on the market

At the AMS Summit, industry leaders went into an in-depth discussion on the commercialisation of 3D bioprinting. Several companies that focus on bioprinting tissues or implants rather than organs themselves already have go-to-market products – like Particle3D, Aspect Biosystems, Rokit Healthcare, Viscient Biosciences, Dimension Inx, and Poietis. But of course, major players on the field like Swedish CELLINK or US-based Organovo also have their technologies on the market already.

The pioneers of 3D bioprinting

The most well-known tissue engineering company is the San Diego-based company, Organovo. It has been actively developing a line of human tissues for use in medical research and drug discovery. They create highly customised 3D human tissues as dynamic models of healthy and diseased human biology for drug development and recently have been in the news for creating miniature human kidneys in the lab, together with the Murdoch Children’s Research Institute.

Today the company still lacks the much-talked-about FDA-approval to its technology. It focuses on replacing animals in testing processes, novel drug discovery and custom disease models, as well as single-cell RNA sequencing. Organovo seeks to have multiple IND filings with the FDA by the end of 2025.

CELLINK has been doing great over the past months. The company develops both bioprinters and bioprinting materials for providing ready-to-print or use models for researchers and healthcare providers to enable 3D cell culture, personalised medicine, and enhanced therapeutics. Their approach helped to decrease the price of bioprinting devices enormously, which allowed more and more research or education institutions and organisations to buy one of these machines – and this inevitably led to even more research and more breakthrough in the industry. Through acquisitions and cooperations, CELLINK indeed became a bioconvergence powerhouse.

Biotech veteran, US-based United Therapeutics develops pharmaceuticals to treat vascular diseases and cancer. The company started bioprinting kidneys, together with Israeli CollPlant, to use the latter’s unique bioink technology and human collagen in the process that aims to reduce worldwide organ shortages.

With 3D bioprinting against testing drugs on animals

Bioprinting can also help eliminate the need for testing new drugs on animals. Replacing lengthy and expensive clinical trials, which often have no results, is a good market opportunity whereby pharma companies could save billions of dollars. Testing medication on mice, rabbits or other animals is in many cases not efficient as the particular drug could still have a different effect on people.

On the other hand, 3D printed tissue proves to be an effective means of testing new pharmaceuticals, meaning that drugs can be thoroughly assessed and brought to market more quickly, all without harming animal test subjects. Moreover, as testing of cosmetics on animals has always been even more controversial than testing for medical purposes, with the emergence of 3D printing human skin, testing cosmetics on animals could disappear once and for all.

In situ bioprinting

The solution means 3D printing tissues directly at the point of injury – no matter whether it’s about bones, tissues or skin. In the next decade, doctors may, therefore, be able to scan wounds and spray on layers of cells to heal them very rapidly. The first results are already out: Australian researchers from UNSW Sydney developed a ceramic-based ink that can print bone-like structures without the use of chemicals or radiation. This technology may help surgeons to 3D print bone parts with living cells – practically to print a replacement bone, including living cells, directly inside a patient’s body.

Scientists in China are also working on “in vivo in situ” solutions and developed a tool that can carry out tissue repair inside the body, used on patients with gastric wounds.

The challenges of 3D bioprinting

The Medical Futurist doesn’t like to ruin optimistic and positive visions for the future, but bioprinting faces severe challenges from technological, financial, and regulatory perspectives.

The most burning issue is the question of regulation. Leaving the market unregulated might lead to a thriving black market. As soon as scaffolds are available and methods are open source, people worldwide might be tempted to start printing unregulated and untested biomaterials and sell them to desperate people.

The FDA has a short segment on 3D bioprinting, but it does not explicitly cover living cells. Those applications are due to go through the FDA’s Center for Biologics Evaluation and Research. As the FDA does not regulate bioprinting but the medical devices and solutions coming out of the printers, regulations still lag behind the technology’s speed.

A 2020 October decision to give 510k clearance to A.D.A.M., a Ukrainian company to work on 3D printed bone implants out of bioceramics, however, indicated that the regulatory body is about to speed up in the field. A.D.A.M. is already in the testing phase and expected to be on the market in 2022 – after getting the FDA approval.

3D Bioprinting is an overly complicated technology, and its many technological, biological challenges; ethical and regulatory issues can already be seen from this brief introduction. It won’t be applied in practice overnight, but it’s going to be a reality to deal with within a decade.

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