Hundreds of thousands of people could be cured of autoimmune diseases like arthritis, multiple sclerosis, diabetes and lupus after scientists discovered how to make stem cell transplants safe.
Autoimmune diseases trigger the body into attacking itself but transplants of bone marrow stem cells from healthy donors have been shown to reset the immune system and reverse fatal conditions.
However doctors have been reluctant to carry out the treatments as before the healthy cells can be given, the patient must be stripped of the malfunctioning immune system using radiotherapy or chemotherapy.
If and when this is accomplished, it will be a whole new era in disease treatment and regenerative medicine
In 20 per cent of cases the patient dies from this stripping procedure and usually surgeons will not attempt a transplant unless there is no other hope.
But Stanford University has now shown it is possible to remove the defective immune system using a new technique which encourages the body to eat up the malfunctioning blood cells.
So far, researchers have proven it works in animals but are hopeful that it will also be effective in humans.
“If it works in humans like it did in mice, we would expect that the risk of death from blood stem cell transplant would drop from 20 per cent to effectively zero,” Dr Judith Shizuru, professor of medicine at Stanford.
“The chemotherapy and radiation used for transplant damage DNA and can cause both immediate problems and long-term damage to many tissues in the body.
“Among the many known toxic side effects, these treatments can cause damage to the liver, reproductive organs and brain, potentially causing seizures and impairing neurological development and growth in children.”
The scientists have developed antibodies which latch onto malfunctioning blood stem cells and flag them up to “waste disposal” cells known as macrophages whose job is to eat up harmful material in the body.
The treatment completely clears the way for transplanted blood stem cells from a donor to take up residence in the bone marrow and generate a whole new blood and immune system.
It means that any disease caused by the patient’s own blood and immune cells, including blood cancers, could potentially be cured by a one-time application of blood stem cell transplantation, say the scientists.
It is estimated that around 1.8 million people in Britain suffer from an autoimmune disease, while 25,000 people a year are diagnosed with blood cancers .
The technique could make organ transplants safer. Currently, people who get an organ transplant must for the rest of their lives stay on drugs that keep their immune systems from attacking the transplanted organ.
But if blood and immune stem cells from the organ donor can be transplanted at the same time as the organ, the new immune system will recognise the donated organ and not attack it.
“If and when this is accomplished, it will be a whole new era in disease treatment and regenerative medicine,” said Dr Irving Weissman, professor of pathology and director of the Stanford Institute for Stem Cell Biology and Regenerative Medicine.
“There is almost no category of disease or organ transplant that is not impacted by this research.”
The research was published in the journal Science Translational Medicine.