Last summer, U.S. Army Lieutenant Colonel Jason Barnhill traveled to an undisclosed desert location in Africa with a ruggedized 3D printer and other basic supplies that could be used to biofabricate for field medical care, such as human mesenchymal stem/stromal cells (hMSCs). The aim was to discover how a 3D bioprinter could expedite healing and even replace damaged tissue for troops injured in combat.

Jason Barnhill with a 3D bioprinter that could replace damaged tissues for troops injured on the battlefield. (Image: Military Health System/West Point)

Barnhill, who is the life science program director of the United States Military Academy West Point Department of Chemistry and Life Sciences, is leading a project with a team of cadets working on experiments to advance bioprinting research in the field with an ultimate goal to develop technology for creating wound-healing biologics, bandages, and more for soldiers on-site or near the point-of-care. According to U.S. Army news, 26 first-class cadets at the United States Military Academy at West Point, in New York, are doing bioprinting research across seven different projects: two teams are working on biobandages for burn and field care; other two teams are working on how to bioengineer blood vessels to enable other bioprinted items that require a blood source, such as organs, to be viable; while one team is working on printing a viable meniscus, and another team is looking to print a liver.

A lot of this has to do with the bioink that we want to use, exactly what material were using as our printer ink, if you will, explained Class of 2020 cadet Allen Gong, a life science major conducting research for the meniscus project. Once we have that 3D model where we want it, then its just a matter of being able to stack the ink on top of each other properly.

Gong, along with his teammates, are researching how to use bioinks to create a meniscus that could be implanted into a soldiers injured knee, while other cadets are seeking to print a liver that could be used to test medicine and maybe one day eliminate the shortage of transplantable organs. This is not the first time we hear the U.S. Army is using bioprinting for regenerative medicine, after all, they often suffer from trauma, resulting in loss of limbs, injuries to the face and severe burns. Deployed soldiers confront the risks of battle on a daily basis. However, being able to have immediate access to specialized bioprinters created to solve catastrophic medical injuries could be the dream-scenario solution many have been waiting for.

In 2014, scientists at the Armed Forces Institute of Regenerative Medicine (AFIRM), established by the Department of Defense, were using 3D bioprinters extensively for skin repair research; but the Army is also actively developing artificial 3D printed hearts, blood vessels, and other organs in a quest to develop customizable and 3D printed medicine. Barnhills pilot program in 2019, conducted by the Uniformed Services University of the Health Sciences (USU) in collaboration with the U.S. Military Academy at West Point, has shown that a 3D printer capable of biofabrication could potentially change the way deployed warfighters receive care also. Under his direction, the 3D printer successfully fabricated a number of products, including a scalpel capable of immediate use and a hemostat (a surgical tool used to control bleeding during surgery and capable of gripping objects) while locking them into place to hold a tissue or other medical implements. The tools were made of a material that could be sterilized on-site, reducing the chance of infection during practical use.

Common combat injuries include second and third-degree burns, broken bones, shrapnel wounds, brain injuries, spinal cord injuries, nerve damage, paralysis, loss of sight and hearing, post-traumatic stress disorder (PTSD), and limb loss. Many of these injuries could be tackled with customizable, on-site bioprinting machines, but for now, the cadets on each of the teams are in the beginning stages of their research before starting the actual printing process. This stage includes reading the research already available in their area of focus and learning how to use the printers, and after spring break, they will have their first chance to start printing with cells. The teams focusing on biobandage, meniscus, and liver will try to print a tangible product by the end of the semester as part of the initial research.

Another cadet and life science major working on the meniscus project, Thatcher Shepard, described in the U.S. Army article that there are definitely some leaps before we can get to that point [of actually implanting what they print]. We have to make sure the body doesnt reject the new bioprinted meniscus and also the emplacement. There can be difficulties with that. Right now, were trying to just make a viable meniscus, then, well look into further research to be able to work on methods of actually placing it into the body.

They claim that the meniscus team is starting with magnetic resonance images (MRI) of knees and working to build a 3D model of a meniscus, which they will eventually be able to print. A great deal of the teams research will be figuring out how and when to implant those cells into the complex cellular structure they are printing.

Cadets at West Point Department of Chemistry and Life Sciences (Image: West Point)

According to Michael Deegan, another life science major and cadet working on one of the blood vessel projects, for now, it will involve a lot of research into what has already been done in the field and the questions that still need to be answered. He described the experience as kind of like putting the cart before the horse. Saying that youve printed it, great, but whats the point of printing it if its not going to survive inside your body? Being able to work on that fundamental step thats actually going to make these organs viable is what drew me and my teammates to be able to do this. Deegan and his colleagues will eventually decide on the scope and direction of their projects, knowing that their research will be key to allowing other areas of the field to move forward, since organs, such as livers and pancreases, have been printed, but so far, they can only be produced at the micro level because they have no blood flow.

While generating organs and blood vessels will be one of the great benefits of customized medicine in the future, the work behind the biobandage teams could have a direct use in the field during combat. The U.S. Army suggests that the goal is to be able to take cells from an injured soldier, specifically one who suffered burns and print a bandage with built-in biomaterial on it to jumpstart the healing process. Medical personnel could potentially be deployed with a 3D printer in their Forward Operating Base or it could be sent along in a column with a Humvee to enable bandages to be printed on-site.

Were researching how the body actually heals from burns, said Channah Mills, a life science major working on one of the biobandage projects. So, what are some things we can do to speed along that process? Introducing a bandage could kickstart that healing process. The faster you start healing, the less scarring and the more likely youre going to recover.

Being on the forefront of it and just seeing the potential in bioengineering, its pretty astounding, Gong said. But it has also been sobering just to see how much more complicated it is to 3D print biomaterials than plastic.

At the moment, the projects are building on existing research on printing sterile bandages and then adding a bioengineering element. The bandages would be printed with specialized skin and stem cells necessary for the healing process.

More than half of the cadets working on the bioprinting projects plan to continue on to medical school following their graduation from West Point. This research, which will be presented during the academys annual Projects Day on April 30, is a great starting point for the future army doctors, as they begin to understand and work on some of the more complex technologies that could become their allies in the future, helping them heal soldiers in the field.

Read more:
West Point: Bioprinting for Soldiers in the Battlefield - 3DPrint.com