Stem cells offer hope for Chagas sufferers
[RIO DE JANEIRO] A study into the use of stem cells conducted by Brazilian researchers has raised hopes for an effective treatment for patients with heart damage caused by Chagas disease, which affects about 16 million people in Latin America.
The Brazilian team injected patients with stem cells derived from the patients' own bone marrow, and were able to reverse cardiac inflammation, a symptom experienced by almost a third of Chagas sufferers that usually leads to death within ten years.
So far the technique has been used successfully in 14 patients suffering from advanced heart damage due to the disease. The results of the study, which substantially increased the quality of life of the patients involved, were published in last month's issue of the American Journal of Pathology.
"We even transplanted stem cells successfully into a patient with the most severe grade of functional heart damage", says immunologist Ricardo Ribeiro dos Santos of the Gonçalo Moniz Research Center, in Salvador, Brazil, who coordinated the study.
"Six months after the transplant, the heart of this patient, who felt short of breath even while talking, is working almost normally."
Experiments with mice that had been genetically modified to exhibit the symptoms of Chagas disease show that the new method can significantly decrease the number of inflammatory cells and reduce fibrosis in the heart. Guinea pigs with significant heart damage treated in the same way also showed an 80 per cent improvement over untreated animals. "The same results were obtained in transplants carried out in humans," says Santos.
The standard treatment for some Chagas disease patients is to carry out a heart transplant, which is 10 to 20 times more expensive than the new method using stem cells, says Santos. The use of stem cells also eliminates other problems related to transplants, such as the scarcity of donors and the risk of rejection.
As Chagas disease mainly affects those in low-income social groups, the researchers have agreed not to seek a patent or any other type of restriction on the use of their treatment.
Chagas disease is caused by the single-celled animal Trypanosoma cruzi, which is transmitted by an insect known as the assassin bug. So far no way has been found of eliminating T. cruzi from the body of an affected individual.