Kacey Marra, PhD, and J. Peter Rubin, MD, are the co-directors of the Adipose Stem Cell Center at the McGowan Institute for Regenerative Medicine. This Center provides the University of Pittsburgh with a focus of expertise in the isolation, growth and differentiation, biology, and therapeutic applications of stem cells derived from adipose (fat) tissues. By partnering physician-researchers with investigators in the fields of tissue engineering, cell therapy, adipose biology, stem cell physiology, and growth and development, the Center is uniquely positioned to translate its findings into new medical treatments. In the Center’s pre-clinical models, adipose-derived stem cells have been used to repair defects in soft tissue, muscle, and bone. In a rat model of nerve injury, adipose-derived stem cells regenerated the sciatic nerve and restored hind leg mobility. Drs. Rubin and Marra are also investigating the use of stem cells as an option for breast reconstruction under a National Institute of Health-funded study.
These McGowan researchers are not alone however in their translation of fat into new medical treatments. Throughout the world, fat tissue is healing broken hearts, killing cancer, and reconstructing breasts.
A team of Melbourne scientists converted excess body fat into potentially life-saving cardiac tissue. Their process involved changing one type of adult stem cell into another by using drugs or growth factors and then growing the new cells into a larger piece of heart tissue. “We've been able to turn fat cells from human patients, which are extracted by liposuction, into cells that have the markers for cardiac progenitors (stem cells)," said Professor Greg Dusting, director of tissue engineering at the Bernard O'Brien Institute of Microsurgery. "You could potentially use them (changed cells) to put back into the patient into a sick heart or … to grow into chunks of heart tissue," Professor Dusting said.
Researchers in Slovakia have been able to derive mesenchymal stem cells from human fat tissue and engineer them into "suicide genes" that seek out and destroy tumors like tiny homing missiles. After extracting the stem cells from human fat tissue the researchers worked to find a less toxic way to treat colon cancer than the standard-of-care chemotherapy agent, 5-fluorouracil (5-FU), which can produce toxic side effects in normal cells. They expanded the number of mesenchymal stem cells in the laboratory and then used a retrovirus vector to insert the gene cytosine deaminase into the cell. This gene can convert a less toxic drug, 5-fluorocytosine (5-FC), to 5-FU inside the stem cells, and the chemotherapy can then seep out into the tumor, producing a lethal by-stander effect. “These fat-derived stem cells could be exploited for personalized cell-based therapeutics," said the study's lead investigator, Cestmir Altaner, PhD, DSc, an associate professor in the Cancer Research Institute of the Slovak Academy of Sciences in Bratislava. "Nearly everyone has some fat tissue they can spare, and this tissue could be a source of cells for cancer treatment that can be adapted into specific vehicles for drug transport."
A Columbia University Medical Center research team, led by Jeremy Mao, DDS, PhD, associate professor of dental medicine, aims to create long-lasting soft tissue implants from mesenchymal stem cells harvested from the patient's own bone marrow or adipose tissue. “Our research has shown that mesenchymal stem cells can create tissue that is biocompatible with the host and that the continuous generation of these cells can replenish the implant to reduce shrinkage,” said Dr. Mao. Using an implant created by placing the stem cells into an FDA-approved scaffold, soft tissue is regenerated, retaining their size and shape. Because of this ability, this is an ideal application for breast reconstruction following cancer surgery.
Illustration: Brisbane Times.
The Adipose Stem Cell Center
UPMC News Bureau (10/26/06)
Brisbane Times (07/08/07)
The Age (07/08/07)
American Association for Cancer Research (07/03/07)
Science Daily (07/05/07)
Medical News Today (06/29/07)
Science Daily (07/01/07)