While questions still remain about the nature and function of stem cells found in fat, a group of researchers and clinicians convened today in Pittsburgh at the Second Annual Meeting of the International Fat Applied Technology Society (IFATS) agreed that research should move forward with the ultimate goal of performing human clinical trials to test the cells' therapeutic potential for specific indications.
Today concludes scientific sessions exploring how adipose tissue, or fat, can be an abundant source of stem cells that could be used for tissue engineering and regenerative medicine. An important outcome of the meeting was the development of a consensus defining key scientific questions for future study and determining the field's most promising clinical applications.
More than 300,000 liposuction procedures are performed in the United States each year, producing about 150,000 gallons of fat that is normally discarded. In 2001, researchers first reported that such tissue contained stem cells, and since then, additional studies have suggested they can be coaxed into other cell types, such as nerve, bone, muscle and blood vessels; or it may be that they have properties of these cells. Some research has progressed more rapidly, with animal studies indicating potential for the development of treatments for heart attack or bone injury, for example, while results looking at other uses are still quite preliminary.
There are currently no human trials in the United States evaluating the potential of stem cells derived from fat, but in reaching consensus on the most promising clinical applications, those attending the IFATS meeting believe the first clinical attempts in patients should be for repairing or healing bone defects, promoting growth of blood vessels in tissues not receiving sufficient blood supply, and for treating acute or chronic cardiac and peripheral vascular diseases.
Moreover, the group felt the best use of the technology should be to develop therapies using patients' own cells, as opposed to cells that might be donated by other individuals. Because adipose is both abundantly available and easily accessible, it offers a practical source of stem cells.
A key question the group answered was simply what to call the cells, with the decision in favor of the term adipose-derived stem cells, even though it also was agreed that these cells are most likely comprised of multiple cell populations – some that are capable of proliferation and differentiation and other groups consisting of mature cells. The society aims to develop common scientific methods in order to best compare results between studies, and believes that much of the research effort should be directed toward identifying the protein markers for adipose stem cells in order to better understand how they differentiate into other cell types and what factors they secrete.
In developing its consensus, the society focused on three main areas, with separate sessions addressing each. Leading discussions that addressed the biology of the cells was Patricia Zuk, Ph.D., research director, Regenerative Bioengineering and Repair Lab, at the David Geffen School of Medicine, University of California, Los Angeles. The session focusing on scientific methods was led by Jeffrey Gimble, M.D., Ph.D., a professor at the Pennington Biomedical Research Center at Louisiana State University. Discussions on clinical applications and opportunities were moderated by Keith March, M.D., Ph.D., director of the Indiana Center for Vascular Biology and Medicine and professor of medicine at the Indiana University School of Medicine.