Back to the Future
One of the biggest hurdles in diagnosing back disorders has long been how to pinpoint the disc causing a patient’s pain. Now an advanced imaging technique and the power of precision medicine are giving doctors a detailed roadmap to problems in the spine.
“When people experience lower back pain, which is up to 85 percent of the population, they often cannot tell us exactly where it is,” says Debiao Li, PhD, director of the Cedars-Sinai Biomedical Imaging Research Institute. “Our approach is to use a detailed image map that allows you to visualize each part of the spinal cord and the disc.”
The image map that Li describes identifies a biomarker — in this case, an area of low pH — which can often be an indicator of disc degeneration and pain. This biomarker is located via a sophisticated form of magnetic resonance imaging. While traditional methods can be painful and invasive, the new, painless imaging technique yields crucial diagnostic information by finding small chemical changes that indicate injury.
“This approach of pH measurement has many other potential roles,” Li says. “Changes in the body’s metabolic process always precede disease, and lactate accumulation [which causes a decrease in pH] indicates that something is wrong.”
Li and an interdisciplinary team, which includes Dan Gazit, DMD, PhD, co-director of the Skeletal Program in the Board of Governors Regenerative Medicine Institute and the Department of Surgery, received a joint grant from the National Institutes of Health to develop the technique.
With the new imaging technique as a platform, Gazit and his colleagues are taking precision medicine a step further. By using adult stem cells known as induced pluripotent stem cells (iPSCs), they have been able to engineer the repair of skeletal tissue.
“We have developed several novel stem cell therapies for skeletal diseases,” Gazit says. “For instance, in complex fractures that are so severe they would never heal and could lead to amputation, we have developed a technique that causes stem cells to accumulate at the fracture site, and then to activate and heal the injury.”
The iPSCs, derived from a patient’s own skin, are modified to behave like embryonic stem cells. “By applying a very specific treatment to the skin cells, it is possible to bring this cell back into something of an embryonic state, which then allows the cell to be directed into a targeted differentiation,” says Zulma Gazit, PhD, co-director of the Skeletal Program at Cedars-Sinai. “The results so far have been extremely encouraging. We have been able to repair complex fractures using iPSCs and we are now looking into using the same cells as a therapy for back pain.”
Even more exciting to researchers is the wider promise of this approach.
“This information can be integrated into the bigger picture of a patient’s disease, and that means individualized treatment strategies can be developed,” Zulma Gazit says. “The more you can learn about each patient, the more able you are to treat them. That’s the true nature of precision medicine.”