Stem cell banking offered to Japan's nuclear workers
Several health organizations are offering to bank stem cells from workers at the damaged Fukushima Daiichi nuclear power plant as a precaution in the event of major accidental radiation exposure.
“Toranomon Hospital in Tokyo is ready to harvest and bank autologous peripheral-blood stem cells (PBSC) for the nuclear workers upon request,” Tetsuya Tanimoto, of the Japanese Foundation for Cancer Research in Tokyo, and colleagues announced in an April 15 correspondence to Lancet.
It may take years to completely shut down reactors at the plant, according to recent news reports, substantially increasing the risk for health complications among those working to bring the damaged reactors under control.
“If a fatal accident happened to the nuclear workers, the nuclear power industry of Japan would collapse. It would also cause serious damage to the industry and nuclear power policy all over the world,” the researchers wrote. “Therefore, we should prioritize support for the nuclear workers' health.”
They explained that exposure to high levels of radiation could deplete bone marrow causing serious illness among workers, but that the condition could be treated with hemopoietic stem-cell transplants.
But relying on transplants from donors has major limitations, including the time necessary to locate an appropriate donor; the potential for graft failure and graft-versus-host disease (GVHD); and immune suppression that could make already vulnerable donors susceptible to severe infections.
Instead the researchers propose harvesting autologous PBSCs from workers before they are exposed and storing them using cryopreservation – thus eliminating the risk for GVHD and also the use of immunosuppressant drugs.
Other advantages of this method include “more rapid hemopoietic recovery” than is currently available with other stem cell therapies and a “therapeutic role for possible leukemia in the future.”
On the flip side, PBSC transplantation has the potential to treat bone marrow injury only, and not damage sustained to other tissues, such as the gastrointestinal tract, skin or lungs.
Toranomon Hospital is not the only facility to offer stem cell banking in response to the nuclear crisis that resulted from the 9.0 magnitude earthquake and tsunami on March 11.
In a March 29 statement, the Japan Society for Hematopoietic Cell Transplantation announced that it has 107 transplant teams ready to collect and store PBSCs, and another 50 hospitals in Europe have agreed to provide assistance after the European Group for Blood and Marrow Transplantation voiced support.
Critics of the plan say that only a small percentage of the workers may require bone marrow transplants and there is not enough of a consensus among international health agencies or the public to institute such a policy.