Tissue engineering research moves toward tissue and organ transplants, drug testing
Researchers at Partners HealthCare are creating living tissue that will redefine the landscape of organ transplantation, muscle and cartilage reconstruction, and drug discovery.
At Massachusetts General Hospital (MGH) and Brigham and Women’s Hospital (BWH), researchers are growing body parts using 3D modeling and human cells, moving from what the mind can only imagine to the realm of possibility.
MGH’s most recent breakthrough, growing a human ear on rats and sheep, is the first time researchers have been able to do so with minimal distortion.
Composed from a combination of natural materials, metals, and human cells, these custom-made body parts could one day achieve the holy grail of tissue engineering—growing organs for human transplantation.
And at Brigham and Women’s Hospital, researchers are developing models of human tissue that will more accurately predict how patients will react to drugs which are under development.
With these types of research advancements, tissue engineering ultimately could help patients with new organs and reduce adverse drug reactions.
Regenerative medicine, customized for patients
The Laboratory for Tissue Engineering and Organ Fabrication at MGH, partially funded by the Armed Forces Institute of Regenerative Medicine (AFIRM), is working to create living replacement ears and facial muscle for injured soldiers.
“The mission of the AFIRM program is to rapidly move technology from the lab bench toward clinical applications to repair the injuries of severely wounded war fighters. Our primary focus for these programs is to develop technology for clinical applications with less emphasis on scientific discovery,” says Laboratory Director Cathryn Sundback, ScD.
Current clinical approaches to ear reconstruction often produce ears that look artificial. For example, the military commonly uses detachable prosthetic ears, but there are drawbacks to this approach.
“They are not flexible so they must be removed before certain activities like sleeping. Because these ears aren’t permanently attached, they are a constant reminder of their deformity,” says Sundback, who works with Joseph Vacanti, MD, also Laboratory Director at MGH's Laboratory for Tissue Engineering and Organ Fabrication.
Instead, MGH researchers built an ear, which is meant to mimic the look and feel of native ears that are flexible, feel comfortable while sleeping, and are customized to the patient.
Using computer technology, researchers created “scaffolding” to help maintain the shape of engineered ear cartilage. Like the inner architecture of a building, the scaffolding—made of thin titanium wire—provides a supporting framework. The ear-shaped scaffolding is then covered with collagen and added with cartilage-forming cells.
Researchers tested this concept on animals and found that the ears maintained their shape with very little shrinkage.
The next step is a GLP (Good Laboratory Practice) study to demonstrate similar results in more sheep subjects and then to apply for FDA approval, says Sundback. Nevertheless, MGH researchers are hopeful that their tissue engineering on humans is not far off.
Sundback notes that one of the major challenges to their research is acquiring a sufficient number of cells. Partner HealthCare offers MGH access to the right cell sources, the Harvard professor explains.
“Our laboratory resides in the Center for Regenerative Medicine at MGH which provides us with the wonderful opportunity to collaborate with some of Boston’s foremost stem cell biologists. Through these relationships, we have access to technology to create stem cells so that we have sufficient numbers of cells for our engineered tissues,” Sundback says.
Building organs for drug testing
Another important application of tissue engineering is an emerging area related to drug testing.
At Brigham and Women’s Hospital, researchers in Dr. Ali Khademhosseini’s lab are creating the materials of cells, tissues, and biological structures that mimic human organs and combining that with nanotechnology for pharmaceutical testing.
Funded by the Defense Threat Reduction Agency under the Department of Defense, BWH creates liver and lung tissues to test the toxicity of certain chemicals or candidate drugs.
“In both of these regenerative medicine and pharmaceutical applications, one of the important things is to make tissues tailored to specific patients. My tissue will not necessarily behave the same way as your tissue,” Khademhosseini says. “Something that may be toxic to me may not be toxic to you. Using this approach allows us to enable this area of personalized medicine.”
BWH uses 3D printing to recreate tissue architecture and vasculature.
“You can really carve out an organ that is specific to a patient,” says Khademhosseini, Associate Professor at Brigham and Women’s Hospital, Harvard, and Massachusetts Institute of Technology.
Described as “organs on a chip,” these micro- and nanoscale technologies can control cells to behave the way they would in the body.
Traditionally, testing new drugs is a time-intensive and expensive process that first tests on animals—which may not be predicative of human reactions—and then when deemed safer, tested on humans. With tissue engineering, researchers can test drugs on human tissue components that are involved in specific diseases and provide a greater understanding of the complexity of the body, rather than just one cell.
“It’s the scientific frontier. In some ways, it’s like the Wild West when it was developing. There are lots of unknowns. There’s huge potential, both scientifically and translational in the impact that you can make,” Khademhosseini says.
Learn more about tissue engineering at MGH and at BWH.
Innovation and Leadership
Partners leadership is dedicated to developing new and improved methods of care delivery, treatments, and cutting-edge research.Learn More