In a recent issue of the Journal of the American Medical Association, Dr. Richard Burt of Northwestern University, Chicago, and his colleagues have reported that Type 1 diabetes patients who underwent a transplant of stem cells from their own bone marrow regained the ability to produce insulin. Researchers said that 20 of the 23 patients became insulin-free for up to four years, including 12 who remained freed continuously for the full four years. While 8 of the 20 patients had to restart insulin at reduced levels, the researchers said that the majority of the patients appear to be experiencing lasting effects from the experimental stem-cell treatment.
To see how well patients were able to produce insulin over the long term, Dr. Burt and his team measured the levels of the marker, C-peptides. They found that levels had increased up to 24 months after transplantation and remained elevated for at least 36 months. “The stem cells appear to have ‘reset’ the patients’ immune system not to attack the islet cells that are involved in the production of natural insulin in the body,” says Dr. Burt. He adds that for those patients who had to restart insulin, they still experienced a significant increase in C-peptide levels after two years.
There is one potential drawback: Because the immune system in a diabetic destroys all of the body’s own islet cells, the treatment will most likely work with people who have been diagnosed within three months of receiving the stem-cell treatment.
While the researchers write that “at the present time this remains the only treatment capable of reversing type 1 diabetes mellitus in humans,” Iain Frame, director of research at the charity Diabetes UK, expresses caution. “Preliminary findings from this small study were reported in 2007. Although this remains an interesting area of research, the importance of a limited extension to this study should not be overstated – this is not a cure for type 1 diabetes,” he says. And he adds: “We would like to see this experiment carried out with a control group for comparison of results and a longer-term follow-up in a greater number of people.”
News Release: Diabetics in stem-cell trial go for years without insulin jab www.timesonline.co.uk April 15, 2009
