Stanford cardiologist and stem cell researcher Joseph Wu, MD, PhD, and his colleagues have published an interesting perspective piece (subscription required) in today's Science Translational Medicine about the body's immune response to transplanted stem cells, which could stymie any future therapeutic use of the cells.
Unfortunately, both embryonic stem cells, or ESC, (which were once thought to possess a free pass into the body) and induced pluripotent stem cells, or iPS cells, (which can be generated from a patient's own cells) can trigger the body to fight back against what it perceives as foreign invaders.
Furthermore, says Wu, who co-directs Stanford's Cardiovascular Institute, it may be most useful in the long run to use tried-and-true iPS cells from an anonymous donor (a process known as 'allogenic' transplantation), rather than creating a new, untested line from each patient. He writes:
We have been interested in developing immuno-tolerance protocols for ESC-based cardiac therapies for patients with ischemic heart disease. We also recognize that, for iPSCs, it may be most cost-effective to treat patients with allogenic cells. Hence this is a very active area of investigation in our lab.
Wu has had two previous reports published on this issue. He and his colleagues conclude in the current paper that it's critical to understand the immune response to stem cells and how best to mitigate it:
For regenerative medicine to fulfill its initial grand promise to revolutionize modern medicine, the immunogenic barrier must be successfully and comprehensively addressed.