Nav: Home

3-D printing produces cartilage from strands of bioink

June 27, 2016

Strands of cow cartilage substitute for ink in a 3D bioprinting process that may one day create cartilage patches for worn out joints, according to a team of engineers. "Our goal is to create tissue that can be used to replace large amounts of worn out tissue or design patches," said Ibrahim T. Ozbolat, associate professor of engineering science and mechanics. "Those who have osteoarthritis in their joints suffer a lot. We need a new alternative treatment for this."

Cartilage is a good tissue to target for scale-up bioprinting because it is made up of only one cell type and has no blood vessels within the tissue. It is also a tissue that cannot repair itself. Once cartilage is damaged, it remains damaged.

Previous attempts at growing cartilage began with cells embedded in a hydrogel -- a substance composed of polymer chains and about 90 percent water -- that is used as a scaffold to grow the tissue.

"Hydrogels don't allow cells to grow as normal," said Ozbolat, who is also a member of the Penn State Huck Institutes of the Life Sciences. "The hydrogel confines the cells and doesn't allow them to communicate as they do in native tissues."

This leads to tissues that do not have sufficient mechanical integrity. Degradation of the hydrogel also can produce toxic compounds that are detrimental to cell growth.

Ozbolat and his research team developed a method to produce larger scale tissues without using a scaffold. They create a tiny -- from 3 to 5 one hundredths of an inch in diameter -- tube made of alginate, an algae extract. They inject cartilage cells into the tube and allow them to grow for about a week and adhere to each other. Because cells do not stick to alginate, they can remove the tube and are left with a strand of cartilage. The researchers reported their results in the current issue of Scientific Reports.

The cartilage strand substitutes for ink in the 3D printing process. Using a specially designed prototype nozzle that can hold and feed the cartilage strand, the 3D printer lays down rows of cartilage strands in any pattern the researchers choose. After about half an hour, the cartilage patch self-adheres enough to move to a petri dish. The researchers put the patch in nutrient media to allow it to further integrate into a single piece of tissue. Eventually the strands fully attach and fuse together.

"We can manufacture the strands in any length we want," said Ozbolat. "Because there is no scaffolding, the process of printing the cartilage is scalable, so the patches can be made bigger as well. We can mimic real articular cartilage by printing strands vertically and then horizontally to mimic the natural architecture."

The artificial cartilage produced by the team is very similar to native cow cartilage. However, the mechanical properties are inferior to those of natural cartilage, but better than the cartilage that is made using hydrogel scaffolding. Natural cartilage forms with pressure from the joints, and Ozbolat thinks that mechanical pressure on the artificial cartilage will improve the mechanical properties.

If this process is eventually applied to human cartilage, each individual treated would probably have to supply their own source material to avoid tissue rejection. The source could be existing cartilage or stem cells differentiated into cartilage cells.
-end-
Also working on this project were Yin Yu, recent Ph.D. from the University of Iowa now at Harvard University; Kazim K Moncal, graduate student in engineering science and mechanics and member of the Huck Institute, Penn State; Weijie Peng, visiting scholar in engineering science and mechanics, Penn State; Iris Rivero, associate professor of industrial manufacturing and systems engineering and Jianqiang Li, former student, Iowa State University; and James A. Martin, associate professor of orthopaedics and rehabilitation, the University of Iowa. The National Science Foundation, Grow Iowa Value Funds and the China Scholarship Fund supported this work.

Penn State

Related Cartilage Articles:

Artificial cartilage under tension as strong as natural material
Biomedical engineers at the University of California, Davis, have created a lab-grown tissue similar to natural cartilage by giving it a bit of a stretch.
Success in the 3-D bioprinting of cartilage
A team of researchers at Sahlgrenska Academy has managed to generate cartilage tissue by printing stem cells using a 3-D-bioprinter.
3-D bioprinted human cartilage cells can be implanted
Swedish researchers at Chalmers University of Technology and Sahlgrenska Academy have successfully induced human cartilage cells to live and grow in an animal model, using 3-D bioprinting.
Better cartilage map could help researchers improve engineered joint repair
Cartilage serves as a shock absorber for the human body, lubricating joints and helping them move smoothly.
Stem cells from jaw bone help repair damaged cartilage
Researchers from Columbia College of Dental Medicine have identified stem cells in the jaw bone that can make new cartilage and repair damaged joints.
High fat diet improves cartilage repair in mice
Obesity is a well-known risk factor for osteoarthritis, but its effects on cartilage repair are unknown.
Stem cells engineered to grow cartilage, fight inflammation
With a goal of treating worn, arthritic hips without extensive surgery to replace them, scientists at Washington University School of Medicine in St.
Radiocarbon dating suggests joint cartilage can't renew
Using radiocarbon dating as a forensic tool, researchers have found that human cartilage rarely renews in adulthood, suggesting that joint diseases may be harder to treat than previously thought.
3-D printing produces cartilage from strands of bioink
Strands of cow cartilage substitute for ink in a 3-D bioprinting process that may one day create cartilage patches for worn out joints, according to a team of engineers.
CWRU leads effort to replace prostheses with engineered cartilage
Case Western Reserve University will open a new center designed to develop evaluation technology and set standards for testing and improving engineered cartilage that could one day replace a variety of prosthetic devices.

Related Cartilage Reading:

Best Science Podcasts 2019

We have hand picked the best science podcasts for 2019. Sit back and enjoy new science podcasts updated daily from your favorite science news services and scientists.
Now Playing: TED Radio Hour

Climate Crisis
There's no greater threat to humanity than climate change. What can we do to stop the worst consequences? This hour, TED speakers explore how we can save our planet and whether we can do it in time. Guests include climate activist Greta Thunberg, chemical engineer Jennifer Wilcox, research scientist Sean Davis, food innovator Bruce Friedrich, and psychologist Per Espen Stoknes.
Now Playing: Science for the People

#527 Honey I CRISPR'd the Kids
This week we're coming to you from Awesome Con in Washington, D.C. There, host Bethany Brookshire led a panel of three amazing guests to talk about the promise and perils of CRISPR, and what happens now that CRISPR babies have (maybe?) been born. Featuring science writer Tina Saey, molecular biologist Anne Simon, and bioethicist Alan Regenberg. A Nobel Prize winner argues banning CRISPR babies won’t work Geneticists push for a 5-year global ban on gene-edited babies A CRISPR spin-off causes unintended typos in DNA News of the first gene-edited babies ignited a firestorm The researcher who created CRISPR twins defends...