Scientists at the Oklahoma Medical Research Foundation have discovered a protein that acts as a gas pedal and brake for so-called “adult” stem cells. The findings, which appear in the current issue of the scientific journal Blood, could have important treatment implications for cancer and other life-threatening diseases.
“This work has a great deal of therapeutic potential,” said Xiao-Hong Sun, Ph.D., the senior author of the paper. “If we can translate the basic research into a method of regulating adult stem cells in humans, it could spell better outcomes for cancer patients who undergo chemotherapy, for leukemia patients undergoing bone marrow transplants, and also for those who suffer from immune deficiencies.”
Using “knock-in” mice—rodents that have been genetically modified with an additional gene—OMRF researchers discovered that a certain protein (known as Id1) controls the proliferation of marrow or “adult” stem cells. These undifferentiated cells spend most of their existence in a slumber-like state in the bone marrow. However, as Sun and her OMRF colleagues discovered, when the body produces (expresses) the Id1 protein, it kicks the stem cells into action, keying their transformation into mature, infection-fighting blood cells.
“Researchers are still a long way from a complete understanding of the process causing stem cells to transform into the blood cells that are the front-line soldiers in the body’s immune system,” said Sun. “But this new discovery provides a clue to solving some key mysteries of human disease.”
“The next step,” said Sun, “is to learn how to manipulate this process. By controlling the stem cells, we potentially can improve outcomes for a host of patients facing life-threatening illnesses.”
The research, which was supported by grants from the National Institute of Allergy and Infectious Disease, used purified stem cells obtained from the bone marrow of the genetically modified mice. This type of stem cells, possessed by humans of all ages, are not to be confused with embryonic stem cells, which are found only in early-stage embryos.
Sun is a member of the Immunobiology and Cancer Research Program at OMRF, where she holds the Eli Lilly Chair in Biomedical Research. She earned her Ph.D. at Cornell University and joined OMRF’s scientific staff in 1999. Her laboratory focuses on understanding the development and function of cells in the immune system.
OMRF (omrf.org) is an independent, nonprofit biomedical research institute dedicated to understanding and developing more effective treatments for human disease. Chartered in 1946, its scientists focus on such critical research areas as Alzheimer’s disease, cancer, lupus and cardiovascular disease.