Like pioneers exploring uncharted territory, researchers like UTSA Assistant Professor of Biomedical Engineering Teja Guda, Ph.D. are bravely discovering new ways to advance medical practices using cutting edge technology.
Guda and his team of graduate and undergraduate students are paving the way for tissue regeneration research through bioprinting, a process that creates tissue-like structures in which a patient’s cells can grow.
Using the EnvisionTEC 3D-Bioplotter, one of only 50 3D printers in the country made specifically for bioprinting, Guda and UTSA doctoral student Joseph Pearson are developing a special silk material mixed with living cells to create structures that will improve the process of performing skeletal and bone grafts.
If the Bioplotter were an actual ink jet printer, Guda said, he and his team would be “in the ink making business.”
Once perfected, the “ink,” or silk material, could produce structures that would successfully incorporate into the body, generate blood vessels, regrow tissue, and “disappear over time,” Guda said.
“Whatever we’d be printing wouldn’t remain in the body for maybe more than a year or two at the most,” he said. “Ideally, for the faster tissues, it could be even as short as two to three months, so you’d pretty much replace (the structure) with your own tissues over time.”
The German-made EnvisionTEC Bioplotter sits in a small, white room in the back of a UTSA Biomedical Engineering laboratory. Only about 10 of these bioprinters are being used for this research in the U.S., Guda said, and UTSA’s could be the only one in Texas.
No one has successfully done so yet, but it’s possible that one day, these bioprinters could print whole organs or chunks of muscle, Guda said. You wouldn’t actually ever need to print an entire organ, though, Guda said, just a small portion would be enough to work in the body.
Over the past six months, Guda and Pearson have been experimenting with the bioprinter to find the right consistency for the silk solution. It would need to be administered at a precise temperature – 37 degrees Celsius, or body temperature – and at a precise speed in order for the cells to stay alive and for the tissue to grow successfully. Guda said that the ideal texture of the solution would be something like toothpaste.
On the computer hooked up to the machine, Guda and Pearson can select whatever shape they want the Bioplotter to print, as well as the amount of layers and the thickness of each one. The computerized 3D model then calibrates to the pointed printer head, which expertly begins to “print out” the material in the chosen shape, layer by layer, as if it were icing a cake.
Doctors typically use metal plates or screws to treat broken bones, which cause scarring. Ideally, using Guda and Pearson’s material, doctors could one day take an injured patient’s CT scan or MRI, convert it into a 3D model on the computer, and calibrate it to the Bioplotter to create a more natural tissue structure, completely customized to the patient’s injury.
They would then insert the “print” into the body where it would foster cell and tissue growth in the affected area.
“So, if you have a patient that has a break or a defect, and you know exactly what size it is based on the image you have, you can potentially use that in this 3D model,” Pearson said. “And with the (silk/cell) material that’s ready to go you can print to that exact specification (of the injury), which is very beneficial because a lot of times we make scaffolds and it’s a cylinder or something that doesn’t necessarily match what’s in your body.”
Guda and Pearson’s silk structures would be a less invasive and more effective approach to treating trauma wounds like those sustained on the battlefield, Guda said. He has already been working with the military in San Antonio on this project for that reason, but also sees opportunity for treating injuries sustained in car wrecks or, especially in Texas, rodeo accidents.
The structures would minimize scarring and could provide the opportunity for a patient with a “busted knee,” for example, to regain more sensation after surgery. If the research continues to develop, children with type 1 diabetes could use Guda and Pearson’s creation when receiving pancreatic islet transplants, a game changer since about 80% of these transplants are rejected by the children’s bodies or don’t last long, Guda said.
With their unique structure, “you get an organ you can’t reject since it’s made of your own cells,” Guda said.
One of Guda and his team’s main goals is perfecting the material so that they can “democratize it, and distribute the technology to clinics and patients as quickly as possible.
“Once we develop the material, the clinicians can just go buy one of (the Bioplotters) and they can print out stuff that we give them materials for and they can do the surgeries,” Guda said. “So the idea is streamlining (the process) and actually getting what we make to patients faster.”
It could be more than five years, at least, before Guda and his research team make it to that point, he said, but in this business, it’s all about taking it one step at a time.
“Some of (these methods) are going to have an impact now, and some of them are going to make life much easier a little down the road,” Guda said. “But it all kind of opens up all of these avenues that we didn’t have before.”
Top Image: UTSA’s EnvisionTEC 3D-Bioplotter is one of only 50 3D printers in the country made specifically for bioprinting. Photo by Kathryn Boyd-Batstone.