The United States is still bogged down in uncertainty over which stem cell science the government can and can't fund, but that doesn't mean the march of research has ground to a halt. This week brought news of two new human stem cell treatments that are going forward. In Britain, a former truck driver in his 60s who suffered a stroke has now become the first person to receive an experimental stem cell treatment for the condition. Doctors injected two million fetal stem cells developed by British company ReNeuron into his brain with the hope of stimulating the growth of brain cells and blood vessels.
The patient received a very low dose of stem cells in an initial trial to assess the safety of the procedure. Over the next year, up to 12 more patients will be given progressively higher doses - again primarily to assess safety - but doctors will be looking closely to see if the stem cells have begun to repair their brains and if their condition has improved. [BBC News]
If those treatments go well, those higher doses could go as high as 10 to 20 million cells. ReNeuron scientist John Sinden explains that the fetal cells were taken from a 12-week-old fetus, and were already destined to become brain cells. This treatment is thought to have fewer uncertainties than those that use embryonic stem cells, which can grow into any type of cell and which can sometimes cause tumors.
Animal studies suggest the cells are safe and effective at healing brain injuries. "We see regrowth of blood vessels, the generation of new neurons, a reduction in scarring and inflammation in the brain," said Sinden. "There are a range of things that happen that are best described as the brain to some extent healing itself." One concern over stem cell therapies has been whether they might cause cancer, but Sinden said the cells used in the latest trial appear not to form tumours. [The Guardian]
It was just last month that a different biotech company, Geron, injected the first spinal cord patient
with a stem cell treatment for new spinal cord injuries. Now the firm StemCells Inc
. has filed for approval of a clinical trial using stem cell treatments for spinal injuries that are up to a year old. Some previous studies have suggested that treatments have to take place in the first few days after injury to have a beneficial effect, but StemCells Inc. says it has gotten promising results from animal tests that bode well for human patients.
A study published earlier this year showed that mice treated with StemCells' nerve stem cells -- which are extracted from aborted fetuses -- were able to walk better than those treated with ordinary human skin cells or a placebo, even when the treatment came weeks after their injury. [Reuters]
If the treatment bears out in human trials, it could benefit a great number of people, the company argues.
"To date, the focus has been on the acute spinal cord injury phase," StemCells CEO Martin McGlynn said in a telephone interview. "That's an important area to address, but the largest unmet need is those who have passed that immediate acute phase of injury."
Geron waited years to garner U.S. government approval for its trial. StemCells Inc. shouldn't have to wait that long, in part because the California-based firm is filing for permission and conducting the trial in Switzerland, and in part because its treatment uses fetal stem cells that were already destined to become nerve cells. In contrast, Geron is using stem cells drawn from embryos. Related Content: 80beats: First Patient Is Injected With Embryonic Stem Cell Treatment