A Victorian man has had stem cells injected into his brain in the world's first trial to treat Parkinson's disease.
The 64-year-old man, who remains unidentified while he recovers, had millions of cells injected into 14 sites in his brain via two 1.5-cm holes in his skull by doctors at the Royal Melbourne Hospital.
Doctors in charge of the trial hoped the stem cells, which can transform into brain cells, would boost levels of dopamine, a neurotransmitter. A deficiency in dopamine can lead to tremors, rigidity and slowness associated with Parkinson's.
The patient was administered 300 micro liters, or 0.3 milliliters, of the pluripotent stem cell, a master cell that can change into any cell in the body, which was frozen and imported from the United States.
Neurologist Andrew Evans and neurosurgeon Girish Nair, the two doctors who carried out the procedure, said it took several months to plan the operation from scratch and receive approval to go ahead.
The two brain experts created a three-dimensional model of the patient's brain, which they used to complete "dummy runs" of the operation.
"The idea with cellular replacement therapy is to be able to implant cells that will differentiate or change from stem cells into cells that either produce dopamine or provide other forms of support to remaining neurons," Evans told News Limited on Wednesday.
Only 1 or 2 percent of the injected cells will become dopamine but pre-trial studies showed that only 10,000 dopamine cells were needed to make a significant difference.
Nair said the slightest mistake in the surgery could have resulted in the death of the patient and injecting the cells too slowly could have resulted in the cells becoming stuck and developing into a tumor.
"The site is very close to the brain stem - the most critical part of the brain - and if you poke around in the wrong places then it could end in paralysis or death," Nair said.
"And if you have a bleed there, even a small one, it's a major stroke."
Evans said it was an enormous relief for the team when scans 24 hours after the surgery revealed the cells had reached all the target sites.
"Despite the long and complex surgery, we left a very small surgical footprint," he said.
The stem cells were derived from unfertilized human egg cells that were manufactured by the International Stem Cell Corporation (ISCC) in the United States.
"Stem cell therapy is a very novel field, but eventually we hope we can use our therapy to cure Parkinson's disease," Russel Kern, chief scientific officer of the ISCC, said.
Kern said the Royal Melbourne Hospital was chosen as the trial's location because of the hospital's strong history of neuroscience research.
While results of the trail will not be known for two years, Nair said stem cell transplants offered the best hope of treating the degenerative brain disease.
"We are dealing with a disease that has a relentless progression and we still don't know how it happens and all the treatments we have so far come with an expiry date," Nair said. "What we are doing here is pushing the frontiers."
Eleven more patients are scheduled to have the surgery in the next year.
