Engineered to heal
Tissue engineering researchers at UT Arlington feel confident that their latest replication efforts will be right at home in a new environment: the human body.
Bioengineering Professor Liping Tang, Associate Professor Jian Yang, and their team of postdoctoral and graduate researchers believe the body—not the laboratory—is the best place to grow bone, muscle, and blood vessels.
First, though, the body needs structure and support intervention to accomplish large healing efforts.
“Our body can regenerate after a small injury,” Dr. Tang says. “However, if a big chunk is missing, such as a chunk of bone, stem cells will go there. But because so much tissue is gone, they don’t know what to turn into, so they become scar tissue.”
In this research, small scaffolds designed for specific tissue tell the stem cells what to become (muscle, bone, etc.) and where and how much to grow. The process is called the orchestrated autologous stem cell regeneration technique, or OASCER.
“We may be able to do everything inside the body,” Tang adds. “The body is the bioreactor.”
The technique is a win-win on several levels. Patients’ bodies would heal with little outside intervention, such as costly and time-consuming tissue engineering in a laboratory. Health industry stakeholders would see reduced expenses.
“It takes a few weeks or a few months for a tissue transplant,” Tang explains. “We get tissue from the patient, such as a skin graft, and grow more tissue in the lab. It’s very expensive, and you can’t mass produce tissue. Tissue engineering has made progress, but it’s not commercially viable today.”
Architecture of the diminutive scaffolds presents a challenge. The small structures must attract stem cells and provide them with instructions and support while they grow. While producing the smooth muscle cells of small blood vessels is somewhat easy, Tang says, it is more difficult to attract enough endothelial cells that provide a slick interior lining for blood to flow smoothly. Bone tissue must grow in a specific sequence to build a strong structure rather than a hollow, fragile one.
The research builds on Tang’s discovery two years ago that stem cells are attracted to implantation of certain materials in the lining of the abdominal cavity of mice. With this method, a patient’s own stem cells could be used for his or her new tissue.
Tang’s group received a grant from the American Heart Association for its vascular research. Members collaborate with Kristine Guleserian at UT Southwestern Medical Center to evaluate whether the OASCER-inspired small-diameter vascular grafts can restore circulation in animals.
The OASCER research could expand into aging and degenerative diseases, Tang says, with knowledge gained from the investigation on healing trauma injuries benefiting people with osteoporosis or muscular dystrophy.