CHICAGO, April 7 (UPI) -- Stem cells transplanted into the brains of Parkinson's disease patients are being damaged -- a setback in treatment, U.S. researchers say.
Study lead author Jeffrey H. Kordower of Rush University Medical Center Chicago said the finding suggests Parkinson's disease is an ongoing process that can affect cells grafted into the brain.
"These findings give us a bit of pause for the value of cell replacement strategy for Parkinson's disease," Kordower said in a statement. "We still need to vigorously investigate this approach among the full armament of surgically delivered Parkinson's disease therapies."
While it is unclear whether the same fate would befall stem cell grafts, the next generation of cell replacement procedures, this study suggests grafted cells can be affected by the disease process, Kordower said.
The study article published in the journal Nature Medicine, described a woman with a 22-year history of Parkinson's disease who experienced improvements and required substantially lower doses of anti-Parkinsonian medications after undergoing transplantation in 1993.
However, by 2004, the woman experienced progressive worsening of Parkinson's disease symptoms and died in 2007. Her brain and that of two other patients in the study were comprehensively processed and analyzed.