Forum for Science, Industry and Business

Sponsored by:     3M 
Search our Site:

 

Gene Therapy Might Grow Replacement Tissue Inside the Body

19.02.2014
Duke researchers use gene therapy to direct stem cells into becoming new cartilage on a synthetic scaffold even after implantation into a living body

By combining a synthetic scaffolding material with gene delivery techniques, researchers at Duke University are getting closer to being able to generate replacement cartilage where it's needed in the body.


An artistic rendering of human stem cells on the polymer scaffolds. Photo courtesy of Charles Gersbach and Farshid Guilak, Duke University

Performing tissue repair with stem cells typically requires applying copious amounts of growth factor proteins—a task that is very expensive and becomes challenging once the developing material is implanted within a body. In a new study, however, Duke researchers found a way around this limitation by genetically altering the stem cells to make the necessary growth factors all on their own.

They incorporated viruses used to deliver gene therapy to the stem cells into a synthetic material that serves as a template for tissue growth. The resulting material is like a computer; the scaffold provides the hardware and the virus provides the software that programs the stem cells to produce the desired tissue.

The study appears online the week of Feb. 17 in the Proceedings of the National Academy of Sciences.

Farshid Guilak, director of orthopaedic research at Duke University Medical Center, has spent years developing biodegradable synthetic scaffolding that mimics the mechanical properties of cartilage. One challenge he and all biomedical researchers face is getting stem cells to form cartilage within and around the scaffolding, especially after it is implanted into a living being.

The traditional approach has been to introduce growth factor proteins, which signal the stem cells to differentiate into cartilage. Once the process is under way, the growing cartilage can be implanted where needed.

“But a major limitation in engineering tissue replacements has been the difficulty in delivering growth factors to the stem cells once they are implanted in the body,” said Guilak, who is also a professor in Duke’s Department of Biomedical Engineering. “There’s a limited amount of growth factor that you can put into the scaffolding, and once it’s released, it’s all gone. We need a method for long-term delivery of growth factors, and that’s where the gene therapy comes in.”

For ideas on how to solve this problem, Guilak turned to his colleague Charles Gersbach, an assistant professor of biomedical engineering and an expert in gene therapy. Gersbach proposed introducing new genes into the stem cells so that they produce the necessary growth factors themselves.

But the conventional methods for gene therapy are complex and difficult to translate into a strategy that would be feasible as a commercial product.

This type of gene therapy generally requires gathering stem cells, modifying them with a virus that transfers the new genes, culturing the resulting genetically altered stem cells until they reach a critical mass, applying them to the synthetic cartilage scaffolding and, finally, implanting it into the body.

“There are a few challenges with that process, one of them being that there are way too many extra steps,” said Gersbach. “So we turned to a technique I had previously developed that affixes the viruses that deliver the new genes onto a material’s surface.”

The new study uses Gersbach’s technique—dubbed biomaterial-mediated gene delivery—to induce the stem cells placed on Guilak’s synthetic cartilage scaffolding to produce growth factor proteins. The results show that the technique works and that the resulting composite material is at least as good biochemically and biomechanically as if the growth factors were introduced in the laboratory.

“We want the new cartilage to form in and around the synthetic scaffold at a rate that can match or exceed the scaffold’s degradation,” said Jonathan Brunger, a graduate student who has spent time in both Guilak’s and Gersbach’s laboratories developing and testing the new technique. “So while the stem cells are making new tissue (in the body), the scaffold can withstand the load of the joint. In the ideal case, one would eventually end up with a viable cartilage tissue substitute replacing the synthetic material.”

While this study focuses on cartilage regeneration, Guilak and Gersbach say that the technique could be applied to many kinds of tissues, especially orthopaedic tissues such as tendons, ligaments and bones. And because the platform comes ready to use with any stem cell, it presents an important step toward commercialization.

“One of the advantages of our method is getting rid of the growth factor delivery, which is expensive and unstable, and replacing it with scaffolding functionalized with the viral gene carrier,” said Gersbach. “The virus-laden scaffolding could be mass-produced and just sitting in a clinic ready to go. We hope this gets us one step closer to a translatable product.”

This work was supported in part by the Nancy Taylor Foundation for Chronic Diseases, the Arthritis Foundation, the AO Foundation, the National Science Foundation (CAREER Award CBET-1151035) and the National Institutes of Health (AR061042, AR50245, AR48852, AG15768, AR48182, AG46927 and OD008586).

CITATION: “Scaffold-mediated lentiviral transduction for functional tissue engineering of cartilage.” Brunger, J.M., Huynh, N.P.T., Guenther, C.M., Perez-Pinera, P., Moutos, F.T., Sanchez-Adams, J., Gersbach C.A., and Guilak F. PNAS Plus, 2014. DOI: 10.1073/pnas.1321744111/-/DCSupplemental

Ken Kingery | EurekAlert!
Further information:
http://www.duke.edu
http://www.pratt.duke.edu/news/gene-therapy-might-grow-replacement-tissue-inside-body

More articles from Life Sciences:

nachricht Chains of nanogold – forged with atomic precision
23.09.2016 | Suomen Akatemia (Academy of Finland)

nachricht Self-assembled nanostructures hit their target
23.09.2016 | King Abdullah University of Science and Technology

All articles from Life Sciences >>>

The most recent press releases about innovation >>>

Die letzten 5 Focus-News des innovations-reports im Überblick:

Im Focus: OLED microdisplays in data glasses for improved human-machine interaction

The Fraunhofer Institute for Organic Electronics, Electron Beam and Plasma Technology FEP has been developing various applications for OLED microdisplays based on organic semiconductors. By integrating the capabilities of an image sensor directly into the microdisplay, eye movements can be recorded by the smart glasses and utilized for guidance and control functions, as one example. The new design will be debuted at Augmented World Expo Europe (AWE) in Berlin at Booth B25, October 18th – 19th.

“Augmented-reality” and “wearables” have become terms we encounter almost daily. Both can make daily life a little simpler and provide valuable assistance for...

Im Focus: Artificial Intelligence Helps in the Discovery of New Materials

With the help of artificial intelligence, chemists from the University of Basel in Switzerland have computed the characteristics of about two million crystals made up of four chemical elements. The researchers were able to identify 90 previously unknown thermodynamically stable crystals that can be regarded as new materials. They report on their findings in the scientific journal Physical Review Letters.

Elpasolite is a glassy, transparent, shiny and soft mineral with a cubic crystal structure. First discovered in El Paso County (Colorado, USA), it can also be...

Im Focus: Complex hardmetal tools out of the 3D printer

For the first time, Fraunhofer IKTS shows additively manufactured hardmetal tools at WorldPM 2016 in Hamburg. Mechanical, chemical as well as a high heat resistance and extreme hardness are required from tools that are used in mechanical and automotive engineering or in plastics and building materials industry. Researchers at the Fraunhofer Institute for Ceramic Technologies and Systems IKTS in Dresden managed the production of complex hardmetal tools via 3D printing in a quality that are in no way inferior to conventionally produced high-performance tools.

Fraunhofer IKTS counts decades of proven expertise in the development of hardmetals. To date, reliable cutting, drilling, pressing and stamping tools made of...

Im Focus: Launch of New Industry Working Group for Process Control in Laser Material Processing

At AKL’16, the International Laser Technology Congress held in May this year, interest in the topic of process control was greater than expected. Appropriately, the event was also used to launch the Industry Working Group for Process Control in Laser Material Processing. The group provides a forum for representatives from industry and research to initiate pre-competitive projects and discuss issues such as standards, potential cost savings and feasibility.

In the age of industry 4.0, laser technology is firmly established within manufacturing. A wide variety of laser techniques – from USP ablation and additive...

Im Focus: New laser joining technologies at ‘K 2016’ trade fair

Every three years, the plastics industry gathers at K, the international trade fair for plastics and rubber in Düsseldorf. The Fraunhofer Institute for Laser Technology ILT will also be attending again and presenting many innovative technologies, such as for joining plastics and metals using ultrashort pulse lasers. From October 19 to 26, you can find the Fraunhofer ILT at the joint Fraunhofer booth SC01 in Hall 7.

K is the world’s largest trade fair for the plastics and rubber industry. As in previous years, the organizers are expecting 3,000 exhibitors and more than...

All Focus news of the innovation-report >>>

Anzeige

Anzeige

Event News

Experts from industry and academia discuss the future mobile telecommunications standard 5G

23.09.2016 | Event News

ICPE in Graz for the seventh time

20.09.2016 | Event News

Using mathematical models to understand our brain

16.09.2016 | Event News

 
Latest News

Chains of nanogold – forged with atomic precision

23.09.2016 | Life Sciences

New leukemia treatment offers hope

23.09.2016 | Health and Medicine

Self-assembled nanostructures hit their target

23.09.2016 | Life Sciences

VideoLinks
B2B-VideoLinks
More VideoLinks >>>