SAN DIEGO, California -- Doctors have surgically implanted genetically modified tissue into the brain of a patient with Alzheimer's disease in a complicated 11-hour operation aimed at preventing cell death associated with the devastating illness, officials said on Tuesday.
The groundbreaking procedure was performed by doctors at the University of California at San Diego School of Medicine, launching the first phase of an experimental gene therapy protocol for the progressive brain disease that preys primarily on the elderly.
The surgery was performed on April 5 at a UCSD hospital in the San Diego suburb of La Jolla on a 60-year-old woman in the early stages of Alzheimer's disease, the university said in a statement. The patient is recovering well, and was discharged from the hospital last Saturday, according to the statement.
The patient is a former teacher from Oregon who was diagnosed with Alzheimer's disease three years ago, the university said. The patient and her family have requested anonymity.
The doctors are trying to prevent cell loss in Alzheimer's disease using gene therapy to deliver a natural brain-survival molecule called nerve growth factor (NGF) to the dying cells in the brain. The surgical procedure was led by UCSD neurosurgeon Dr. Hoi Sang U, who implanted the tissue in the patient's brain using specially designed surgical tools, according to the statement.
The program, led by UCSD neurologist Dr. Mark Tuszynski, represents the initial attempt by doctors to use human gene therapy to address a disease of the nervous system.
"We have four children and one grandchild. If there is a genetic trail associated with this disease, we are concerned about their future," the patient's husband said in a statement released by the school. "Our main motivation is to see if we can contribute to patient care in the future by participating in this study. If there are benefits for my wife, that will be a plus."
Tuszynski said, "NGF gene therapy is not expected to cure Alzheimer's disease, but we hope that it might protect and even restore certain brain cells and alleviate some symptoms, such as short-term memory loss, for a period that could last a few years."
Tuszynski said that "it may take several years to test the procedure in a large enough number of patients to determine whether it will be useful therapy."
Alzheimer's disease is a progressive, neurodegenerative disease marked by loss of function and death of nerve cells in several areas of the brain, leading to loss of mental functions such as memory and learning.
According to the Alzheimer's Association, one in 10 people over age 65 and nearly half of those over 85 have Alzheimer's disease. Four million Americans have Alzheimer's disease.
One of the characteristic structural abnormalities found in the brains of individuals with Alzheimer's are amyloid plaques, clusters of dead and dying nerve cells, other brain cells and amyloid protein fragments.
The so-called Phase I clinical trial, also called a "safety/toxicity" study, was designed to determine whether the gene-transplantation procedure is safe, the university said.
This procedure targeted a class of cells located deep within the brain in an area called the cholinergic system, important for supporting memory and cognitive function. The system degenerates significantly in the course of the disease.
The cells have been shown to respond to NGF in primate studies, and researchers hope that preventing extensive loss of these cells may slow the intellectual decline seen in Alzheimer's patients.
